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(lstat)4.45 E F0(,)A F1(msgctl)4.45 E F0(,)A F1(msgget)4.45 E F0(,)A F1
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(Also note that, for the superuser on the local \214lesystems, the)128
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(Returns the arctangent of Y/X in the range \255PI to)128 549.6 Q F1(PI)
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(does not.)2.5 E 1.087(If the \214lehandle came from a piped open,)128
536.4 R F1(close)3.587 E F0 1.087(returns f)3.587 F 1.087
(alse if one of the other syscalls in)-.1 F -.2(vo)-.4 G(lv).2 E(ed)-.15
E -.1(fa)128 548.4 S .173(ils or if its program e).1 F .173
(xits with non-zero status.)-.15 F .173(If the only problem w)5.173 F
.172(as that the program e)-.1 F .172(xited non-)-.15 F(zero,)128 560.4
Q F1($!)2.868 E F0 .368(will be set to)5.368 F F1(0)2.868 E F0 5.368(.C)
C .368(losing a pipe also w)-5.368 F .369(aits for the process e)-.1 F
-.15(xe)-.15 G .369(cuting on the pipe to e).15 F -.834(xit \212 in)-.15
F .141(case you wish to look at the output of the pipe afterw)128 572.4
R -.834(ards \212 and)-.1 F .141(implicitly puts the e)2.641 F .141
(xit status v)-.15 F .141(alue of)-.25 F(that command into)128 584.4 Q
F1($?)2.5 E F0(and)2.5 E F1(${^CHILD_ERROR_NATIVE})2.5 E F0(.)A .875
(If there are multiple threads running,)128 602.4 R F1(close)3.375 E F0
.876(on a \214lehandle from a piped open returns true without)3.376 F
-.1(wa)128 614.4 S(iting for the child process to terminate, if the \
\214lehandle is still open in another thread.).1 E .058(Closing the rea\
d end of a pipe before the process writing to it at the other end is do\
ne writing results in)128 632.4 R .823(the writer recei)128 644.4 R .823
(ving a)-.25 F F2(SIGPIPE)3.323 E F0 5.823(.I)C 3.323(ft)-5.823 G .823
(he other end can')-3.323 F 3.324(th)-.18 G .824
(andle that, be sure to read all the data before)-3.324 F
(closing the pipe.)128 656.4 Q(Example:)128 674.4 Q(perl v5.14.2)72 768
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(open\(OUTPUT, \010|sort >foo\010\))152 84 Q 6(#p)12 G(ipe to sort)-6 E
(or die "Can\010t start sort: $!";)176 96 Q 138(#... #)152 108 R
(print stuff to output)6 E(close OUTPUT)152 120 Q 6(#w)96 G
(ait for sort to finish)-6 E(or warn $! ? "Error closing sort pipe: $!")
176 132 Q 6(:")242 144 S(Exit status $? from sort";)-6 E
(open\(INPUT, \010foo\010\))152 156 Q 6(#g)60 G(et sort\010s results)-6
E(or die "Can\010t open \010foo\010 for input: $!";)176 168 Q/F2 9
/Times-Roman@0 SF(FILEHANDLE)128 186 Q F0 .145(may be an e)2.646 F .145
(xpression whose v)-.15 F .145
(alue can be used as an indirect \214lehandle, usually the real)-.25 F
(\214lehandle name or an auto)128 198 Q(vi)-.15 E(vi\214ed handle.)-.25
E(closedir)108 214.8 Q F2(DIRHANDLE)2.5 E F0
(Closes a directory opened by)128 226.8 Q F1(opendir)2.5 E F0
(and returns the success of that system call.)2.5 E(connect)108 243.6 Q
F2(SOCKET)2.5 E F0(,N)A(AME)-.35 E 2.102
(Attempts to connect to a remote sock)128 255.6 R 2.102(et, just lik)-.1
F(e)-.1 E/F3 10/Times-Italic@0 SF(connect)4.602 E F0 4.602
(\(2\). Returns)1.666 F 2.103(true if it succeeded, f)4.602 F(alse)-.1 E
(otherwise.)128 267.6 Q F2 -.315(NA)5.079 G(ME).315 E F0 .079
(should be a pack)2.579 F .079
(ed address of the appropriate type for the sock)-.1 F 2.578(et. See)-.1
F .078(the e)2.578 F(xamples)-.15 E(in `)128 279.6 Q(`Sock)-.74 E
(ets: Client/Serv)-.1 E(er Communication')-.15 E 2.5('i)-.74 G 2.5(np)
-2.5 G(erlipc.)-2.5 E(continue)108 296.4 Q F2(BLOCK)2.5 E F0(continue)
108 308.4 Q F1(continue)128 320.4 Q F0 2.031(is actually a \215o)4.531 F
4.531(wc)-.25 G 2.031(ontrol statement rather than a function.)-4.531 F
2.032(If there is a)7.032 F F1(continue)4.532 E F2(BLOCK)128 332.4 Q F0
.858(attached to a)3.358 F F2(BLOCK)3.358 E F0 .858(\(typically in a)
3.358 F F1(while)3.357 E F0(or)3.357 E F1(foreach)3.357 E F0 .857
(\), it is al)B -.1(wa)-.1 G .857(ys e).1 F -.15(xe)-.15 G .857
(cuted just before).15 F .513(the conditional is about to be e)128 344.4
R -.25(va)-.25 G .514(luated ag).25 F .514(ain, just lik)-.05 F 3.014
(et)-.1 G .514(he third part of a)-3.014 F F1(for)3.014 E F0 .514
(loop in C.)3.014 F .514(Thus it can)5.514 F .513
(be used to increment a loop v)128 356.4 R .513(ariable, e)-.25 F -.15
(ve)-.25 G 3.013(nw).15 G .513(hen the loop has been continued via the)
-3.013 F F1(next)3.013 E F0(statement)3.012 E
(\(which is similar to the C)128 368.4 Q F1(continue)2.5 E F0
(statement\).)2.5 E F1(last)128 386.4 Q F0(,)A F1(next)2.555 E F0 2.555
(,o)C(r)-2.555 E F1(redo)2.555 E F0 .055(may appear within a)2.555 F F1
(continue)2.555 E F0(block;)2.555 E F1(last)2.555 E F0(and)2.555 E F1
(redo)2.555 E F0(beha)2.556 E .356 -.15(ve a)-.2 H 2.556(si).15 G 2.556
(ft)-2.556 G(he)-2.556 E 2.556(yh)-.15 G(ad)-2.556 E .621(been e)128
398.4 R -.15(xe)-.15 G .621(cuted within the main block.).15 F .621
(So will)5.621 F F1(next)3.121 E F0 3.121(,b)C .62(ut since it will e)
-3.321 F -.15(xe)-.15 G .62(cute a).15 F F1(continue)3.12 E F0 .62
(block, it)3.12 F(may be more entertaining.)128 410.4 Q F1
(while \(EXPR\) {)152 428.4 Q(### redo always comes here)176 440.4 Q
(do_something;)176 452.4 Q 6(}c)152 464.4 S(ontinue {)-6 E
(### next always comes here)176 476.4 Q(do_something_else;)176 488.4 Q 6
(#t)176 500.4 S(hen back the top to re\255check EXPR)-6 E(})152 512.4 Q
(### last always comes here)152 524.4 Q F0 .2(Omitting the)128 542.4 R
F1(continue)2.7 E F0 .2(section is equi)2.7 F -.25(va)-.25 G .201
(lent to using an empty one, logically enough, so).25 F F1(next)2.701 E
F0(goes)2.701 E
(directly back to check the condition at the top of the loop.)128 554.4
Q .049(If the)128 572.4 R F1("switch")2.549 E F0 .048
(feature is enabled,)2.548 F F1(continue)2.548 E F0 .048
(is also a function that f)2.548 F .048(alls through the current)-.1 F
F1(when)2.548 E F0(or)128 584.4 Q F1(default)4.658 E F0 2.158
(block instead of iterating a dynamically enclosing)4.658 F F1(foreach)
4.659 E F0 2.159(or e)4.659 F 2.159(xiting a le)-.15 F(xically)-.15 E
(enclosing)128 596.4 Q F1(given)2.5 E F0 5(.S)C(ee feature and `)-5 E
(`Switch statements')-.74 E 2.5('i)-.74 G 2.5(np)-2.5 G
(erlsyn for more information.)-2.5 E(cos)108 613.2 Q F2(EXPR)2.5 E F0
(cos)108 625.2 Q(Returns the cosine of)128 625.2 Q F2(EXPR)2.5 E F0(\(e)
2.5 E(xpressed in radians\).)-.15 E(If)5 E F2(EXPR)2.5 E F0
(is omitted, tak)2.5 E(es the cosine of)-.1 E F1($_)2.5 E F0(.)A -.15
(Fo)128 643.2 S 4.168(rt).15 G 1.668(he in)-4.168 F -.15(ve)-.4 G 1.668
(rse cosine operation, you may use the).15 F F1(Math::Trig::acos\(\))
4.168 E F0 1.667(function, or use this)4.167 F(relation:)128 655.2 Q F1
(sub acos { atan2\( sqrt\(1 \255 $_[0] * $_[0]\), $_[0] \) })152 673.2 Q
F0(crypt)108 690 Q F2(PLAINTEXT)2.5 E F0(,SAL)A(T)-.92 E .734
(Creates a digest string e)128 702 R .734(xactly lik)-.15 F 3.234(et)-.1
G(he)-3.234 E F3(crypt)3.234 E F0 .734
(\(3\) function in the C library \(assuming that you actually)1.666 F
(ha)128 714 Q .3 -.15(ve a ve)-.2 H(rsion there that has not been e).15
E(xtirpated as a potential munition\).)-.15 E(perl v5.14.2)72 768 Q
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
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(ay hash function.)-.1 F(The)5.452 E/F2 9/Times-Roman@0 SF(PLAINTEXT)
2.952 E F0(and)2.952 E F2(SAL)2.952 E(T)-.828 E F0 .451
(are turned into a short string, called a)2.952 F 1.289
(digest, which is returned.)128 96 R 1.289(The same)6.289 F F2
(PLAINTEXT)3.789 E F0(and)3.789 E F2(SAL)3.789 E(T)-.828 E F0 1.289
(will al)3.789 F -.1(wa)-.1 G 1.289(ys return the same string, b).1 F
(ut)-.2 E 2.612(there is no \(kno)128 108 R 2.612(wn\) w)-.25 F 2.612
(ay to get the original)-.1 F F2(PLAINTEXT)5.112 E F0 2.612
(from the hash.)5.112 F 2.611(Small changes in the)7.612 F F2(PLAINTEXT)
128 120 Q F0(or)2.5 E F2(SAL)2.5 E(T)-.828 E F0(will result in lar)2.5 E
(ge changes in the digest.)-.18 E 1.167(There is no decrypt function.)
128 138 R 1.167(This function isn')6.167 F 3.667(ta)-.18 G 1.168
(ll that useful for cryptograph)-3.667 F 3.668(y\()-.05 G 1.168
(for that, look for)-3.668 F F1(Crypt)128 150 Q F0 .483
(modules on your nearby)2.984 F F2(CP)2.983 E(AN)-.828 E F0 .483
(mirror\) and the name `)2.983 F(`crypt')-.74 E 2.983('i)-.74 G 2.983
(sab)-2.983 G .483(it of a misnomer)-2.983 F 5.483(.I)-.55 G .483
(nstead it)-5.483 F .077(is primarily used to check if tw)128 162 R
2.577(op)-.1 G .077(ieces of te)-2.577 F .077
(xt are the same without ha)-.15 F .077
(ving to transmit or store the te)-.2 F(xt)-.15 E 3.385(itself. An)128
174 R -.15(ex)3.385 G .885(ample is checking if a correct passw).15 F
.885(ord is gi)-.1 F -.15(ve)-.25 G 3.385(n. The).15 F .884
(digest of the passw)3.385 F .884(ord is stored,)-.1 F .393
(not the passw)128 186 R .393(ord itself.)-.1 F .394
(The user types in a passw)5.393 F .394(ord that is)-.1 F F1(crypt\(\))
2.894 E F0 1.394 -.5('d w)D .394(ith the same salt as the stored).5 F
2.5(digest. If)128 198 R(the tw)2.5 E 2.5(od)-.1 G
(igests match, the passw)-2.5 E(ord is correct.)-.1 E .314(When v)128
216 R .314(erifying an e)-.15 F .313
(xisting digest string you should use the digest as the salt \(lik)-.15
F(e)-.1 E/F3 10/Courier@0 SF(crypt\($plain,)2.813 E .259
($digest\) eq $digest)128 228 R F0 2.76(\). The)B F2(SAL)2.76 E(T)-.828
E F0 .26(used to create the digest is visible as part of the digest.)
2.76 F(This)5.26 E(ensures)128 240 Q F1(crypt\(\))3.722 E F0 1.222
(will hash the ne)3.722 F 3.722(ws)-.25 G 1.222
(tring with the same salt as the digest.)-3.722 F 1.221(This allo)6.221
F 1.221(ws your code to)-.25 F -.1(wo)128 252 S .548
(rk with the standard crypt and with more e).1 F .548
(xotic implementations.)-.15 F .548(In other w)5.548 F .548
(ords, assume nothing)-.1 F
(about the returned string itself nor about ho)128 264 Q 2.5(wm)-.25 G
(an)-2.5 E 2.5(yb)-.15 G(ytes of)-2.5 E F2(SAL)2.5 E(T)-.828 E F0
(may matter)2.5 E(.)-.55 E -.35(Tr)128 282 S .15
(aditionally the result is a string of 13 bytes: tw).35 F 2.65<6f8c>-.1
G .15(rst bytes of the salt, follo)-2.65 F .15(wed by 11 bytes from the)
-.25 F(set)128 294 Q F3([./0\2559A\255Za\255z])2.815 E F0 2.815(,a)C
.315(nd only the \214rst eight bytes of)-2.815 F F2(PLAINTEXT)2.815 E F0
.316(mattered. But alternati)2.816 F .616 -.15(ve h)-.25 H(ashing).15 E
2.481(schemes \(lik)128 306 R(e)-.1 E F2(MD5)4.98 E F0 2.48
(\), higher le)B -.15(ve)-.25 G 4.98(ls).15 G 2.48
(ecurity schemes \(lik)-4.98 F 4.98(eC)-.1 G 2.48
(2\), and implementations on non-Unix)-4.98 F(platforms may produce dif)
128 318 Q(ferent strings.)-.25 E .848(When choosing a ne)128 336 R 3.348
(ws)-.25 G .849(alt create a random tw)-3.348 F 3.349(oc)-.1 G .849
(haracter string whose characters come from the set)-3.349 F F3
([./0\2559A\255Za\255z])128 348 Q F0(\(lik)3.847 E(e)-.1 E F3 1.346(joi\
n \010\010, \(\010.\010, \010/\010, 0..9, \010A\010..\010Z\010, \010a\
\010..\010z\010\)[rand)3.847 F .332(64, rand 64])128 360 R F0 2.832
(\). This)B .333
(set of characters is just a recommendation; the characters allo)2.832 F
.333(wed in the salt)-.25 F(depend solely on your system')128 372 Q 2.5
(sc)-.55 G(rypt library)-2.5 E 2.5(,a)-.65 G(nd Perl can')-2.5 E 2.5(tr)
-.18 G(estrict what salts)-2.5 E F3(crypt\(\))2.5 E F0(accepts.)2.5 E
(Here')128 390 Q 2.5(sa)-.55 G 2.5(ne)-2.5 G(xample that mak)-2.65 E
(es sure that whoe)-.1 E -.15(ve)-.25 G 2.5(rr).15 G
(uns this program kno)-2.5 E(ws their passw)-.25 E(ord:)-.1 E F3
($pwd = \(getpwuid\($<\)\)[1];)152 408 Q(system "stty \255echo";)152 432
Q(print "Password: ";)152 444 Q(chomp\($word = <STDIN>\);)152 456 Q
(print "\\n";)152 468 Q(system "stty echo";)152 480 Q
(if \(crypt\($word, $pwd\) ne $pwd\) {)152 504 Q(die "Sorry...\\n";)176
516 Q 6(}e)152 528 S(lse {)-6 E(print "ok\\n";)176 540 Q(})152 552 Q F0
(Of course, typing in your o)128 570 Q(wn passw)-.25 E(ord to whoe)-.1 E
-.15(ve)-.25 G 2.5(ra).15 G(sks you for it is unwise.)-2.5 E .437
(The crypt function is unsuitable for hashing lar)128 588 R .437
(ge quantities of data, not least of all because you can')-.18 F(t)-.18
E(get the information back.)128 600 Q
(Look at the Digest module for more rob)5 E(ust algorithms.)-.2 E .121
(If using)128 618 R F1(crypt\(\))2.621 E F0 .121
(on a Unicode string \(which)2.621 F F1(potentially)2.621 E F0 .122
(has characters with codepoints abo)2.621 F .422 -.15(ve 2)-.15 H .122
(55\), Perl).15 F .615(tries to mak)128 630 R 3.115(es)-.1 G .614
(ense of the situation by trying to do)-3.115 F .614(wngrade \(a cop)
-.25 F 3.114(yo)-.1 G .614(f\) the string back to an eight-bit)-3.114 F
.764(byte string before calling)128 642 R F1(crypt\(\))3.264 E F0 .764
(\(on that cop)3.264 F 3.264(y\). If)-.1 F .764(that w)3.264 F .764
(orks, good.)-.1 F .764(If not,)5.764 F F1(crypt\(\))3.264 E F0 .765
(dies with)3.264 F F3(Wide)3.265 E(character in crypt)128 654 Q F0(.)A
(dbmclose)108 670.8 Q F2(HASH)2.5 E F0([This function has been lar)128
682.8 Q(gely superseded by the)-.18 E F3(untie)2.5 E F0(function.])2.5 E
(Breaks the binding between a)128 700.8 Q F2(DBM)2.5 E F0
(\214le and a hash.)2.5 E(perl v5.14.2)72 768 Q 198.17(2011-10-01 13)
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/F1 9/Times-Roman@0 SF(HASH)2.5 E F0(,DBN)A(AME,MASK)-.35 E
([This function has been lar)128 96 Q(gely superseded by the)-.18 E/F2
10/Courier@0 SF(tie)2.5 E F0(function.])2.5 E .558(This binds a)128 114
R/F3 10/Times-Italic@0 SF(dbm)3.058 E F0(\(3\),)1.666 E F3(ndbm)3.058 E
F0(\(3\),)1.666 E F3(sdbm)3.058 E F0(\(3\),)1.666 E F3(gdbm)3.058 E F0
.558(\(3\), or Berk)1.666 F(ele)-.1 E(y)-.15 E F1(DB)3.057 E F0 .557
(\214le to a hash.)3.057 F F1(HASH)5.557 E F0 .557(is the name)3.057 F
1.22(of the hash.)128 126 R(\(Unlik)6.22 E 3.72(en)-.1 G(ormal)-3.72 E
F2(open)3.72 E F0 3.72(,t)C 1.22(he \214rst ar)-3.72 F 1.221(gument is)
-.18 F F3(not)3.721 E F0 3.721<618c>3.721 G 1.221(lehandle, e)-3.721 F
-.15(ve)-.25 G 3.721(nt).15 G 1.221(hough it looks lik)-3.721 F(e)-.1 E
(one\).)128 138 Q F1(DBN)5.211 E(AME)-.315 E F0 .211
(is the name of the database \(without the)2.711 F F3(.dir)2.71 E F0(or)
2.71 E F3(.pa)2.71 E(g)-.1 E F0 -.15(ex)2.71 G .21(tension if an).15 F
2.71(y\). If)-.15 F .21(the database)2.71 F .788(does not e)128 150 R
.789(xist, it is created with protection speci\214ed by)-.15 F F1(MASK)
3.289 E F0 .789(\(as modi\214ed by the)3.289 F F2(umask)3.289 E F0 3.289
(\). If)B(your)3.289 E 2.234(system supports only the older)128 162 R F1
(DBM)4.734 E F0 2.234(functions, you may mak)4.734 F 4.734(eo)-.1 G
2.234(nly one)-4.734 F F2(dbmopen)4.734 E F0 2.233(call in your)4.734 F
4.09(program. In)128 174 R 1.59(older v)4.09 F 1.59
(ersions of Perl, if your system had neither)-.15 F F1(DBM)4.091 E F0
1.591(nor ndbm, calling)4.091 F F2(dbmopen)4.091 E F0(produced a f)128
186 Q(atal error; it no)-.1 E 2.5(wf)-.25 G(alls back to)-2.6 E F3(sdbm)
2.5 E F0(\(3\).)1.666 E .396(If you don')128 204 R 2.896(th)-.18 G -2.25
-.2(av e)-2.896 H .396(write access to the)3.096 F F1(DBM)2.896 E F0
.395(\214le, you can only read hash v)2.895 F .395
(ariables, not set them.)-.25 F .395(If you)5.395 F -.1(wa)128 216 S
1.019(nt to test whether you can write, either use \214le tests or try \
setting a dummy hash entry inside an).1 F F2(eval)128 228 Q F0
(to trap the error)2.5 E(.)-.55 E .624(Note that functions such as)128
246 R F2(keys)3.124 E F0(and)3.124 E F2(values)3.124 E F0 .624
(may return huge lists when used on lar)3.124 F(ge)-.18 E F1(DBM)3.124 E
F0(\214les.)3.124 E -1.1(Yo)128 258 S 2.5(um)1.1 G(ay prefer to use the)
-2.5 E F2(each)2.5 E F0(function to iterate o)2.5 E -.15(ve)-.15 G 2.5
(rl).15 G(ar)-2.5 E(ge)-.18 E F1(DBM)2.5 E F0 2.5(\214les. Example:)2.5
F F2 6(#p)152 276 S(rint out history file offsets)-6 E
(dbmopen\(%HIST,\010/usr/lib/news/history\010,0666\);)152 288 Q
(while \(\($key,$val\) = each %HIST\) {)152 300 Q
(print $key, \010 = \010, unpack\(\010L\010,$val\), "\\n";)176 312 Q(})
152 324 Q(dbmclose\(%HIST\);)152 336 Q F0 2.028(See also An)128 354 R
2.029
(yDBM_File for a more general description of the pros and cons of the v)
-.15 F 2.029(arious dbm)-.25 F
(approaches, as well as DB_File for a particularly rich implementation.)
128 366 Q -1.1(Yo)128 384 S 2.5(uc)1.1 G(an control which)-2.5 E F1(DBM)
2.5 E F0(library you use by loading that library before you call)2.5 E
F3(dbmopen\(\))2.5 E F0(:)A F2(use DB_File;)152 402 Q
(dbmopen\(%NS_Hist, "$ENV{HOME}/.netscape/history.db"\))152 414 Q
(or die "Can\010t open netscape history file: $!";)176 426 Q F0(def)108
442.8 Q(ault)-.1 E F1(BLOCK)2.5 E F0 -.4(Wi)128 454.8 S 1.706(thin a).4
F F2(foreach)4.206 E F0 1.706(or a)4.206 F F2(given)4.206 E F0 4.206(,a)
C F2(default)A F1(BLOCK)4.206 E F0 1.705(acts lik)4.206 F 4.205(ea)-.1 G
F2(when)A F0(that')4.205 E 4.205(sa)-.55 G -.1(lwa)-4.205 G 1.705
(ys true.).1 F(Only)6.705 E -.2(av)128 466.8 S
(ailable after Perl 5.10, and only if the)-.05 E F2(switch)2.5 E F0
(feature has been requested.)2.5 E(See `)5 E(`when')-.74 E('.)-.74 E
(de\214ned)108 483.6 Q F1(EXPR)2.5 E F0(de\214ned)108 495.6 Q .578
(Returns a Boolean v)128 507.6 R .578(alue telling whether)-.25 F F1
(EXPR)3.078 E F0 .578(has a v)3.078 F .579
(alue other than the unde\214ned v)-.25 F(alue)-.25 E F2(undef)3.079 E
F0 5.579(.I)C(f)-5.579 E F1(EXPR)128 519.6 Q F0(is not present,)2.5 E F2
($_)2.5 E F0(is check)2.5 E(ed.)-.1 E(Man)128 537.6 Q 2.792(yo)-.15 G
.292(perations return)-2.792 F F2(undef)2.792 E F0 .292(to indicate f)
2.792 F .291(ailure, end of \214le, system error)-.1 F 2.791(,u)-.4 G
.291(ninitialized v)-2.791 F .291(ariable, and)-.25 F .91(other e)128
549.6 R .91(xceptional conditions.)-.15 F .911(This function allo)5.91 F
.911(ws you to distinguish)-.25 F F2(undef)3.411 E F0 .911(from other v)
3.411 F 3.411(alues. \(A)-.25 F .147
(simple Boolean test will not distinguish among)128 561.6 R F2(undef)
2.647 E F0 2.647(,z)C .147(ero, the empty string, and)-2.647 F F2("0")
2.647 E F0 2.647(,w)C .146(hich are all)-2.647 F 1.126(equally f)128
573.6 R 3.626(alse.\) Note)-.1 F 1.126(that since)3.626 F F2(undef)3.626
E F0 1.127(is a v)3.627 F 1.127(alid scalar)-.25 F 3.627(,i)-.4 G 1.127
(ts presence doesn')-3.627 F(t)-.18 E F3(necessarily)3.627 E F0 1.127
(indicate an)3.627 F -.15(ex)128 585.6 S .373(ceptional condition:).15 F
F2(pop)2.873 E F0(returns)2.873 E F2(undef)2.873 E F0 .373(when its ar)
2.873 F .373(gument is an empty array)-.18 F(,)-.65 E F3(or)2.872 E F0
.372(when the element)2.872 F(to return happens to be)128 597.6 Q F2
(undef)2.5 E F0(.)A -1.1(Yo)128 615.6 S 3.748(um)1.1 G 1.248
(ay also use)-3.748 F F2(defined\(&func\))3.748 E F0 1.248
(to check whether subroutine)3.748 F F2(&func)3.749 E F0 1.249(has e)
3.749 F -.15(ve)-.25 G 3.749(rb).15 G 1.249(een de\214ned.)-3.749 F .108
(The return v)128 627.6 R .108(alue is unaf)-.25 F .108(fected by an)
-.25 F 2.608(yf)-.15 G(orw)-2.608 E .108(ard declarations of)-.1 F F2
(&func)2.607 E F0 5.107(.A)C .107(subroutine that is not de\214ned)-2.5
F .463(may still be callable: its package may ha)128 639.6 R .764 -.15
(ve a)-.2 H(n).15 E F2(AUTOLOAD)2.964 E F0 .464(method that mak)2.964 F
.464(es it spring into e)-.1 F(xistence)-.15 E
(the \214rst time that it is called; see perlsub)128 651.6 Q(.)-.4 E
.484(Use of)128 669.6 R F2(defined)2.984 E F0 .484(on aggre)2.984 F -.05
(ga)-.15 G .483(tes \(hashes and arrays\) is deprecated.).05 F .483
(It used to report whether memory)5.483 F 1.203(for that aggre)128 681.6
R -.05(ga)-.15 G 1.203(te had e).05 F -.15(ve)-.25 G 3.703(rb).15 G
1.203(een allocated.)-3.703 F 1.203(This beha)6.203 F 1.204
(vior may disappear in future v)-.2 F 1.204(ersions of Perl.)-.15 F -1.1
(Yo)128 693.6 S 2.5(us)1.1 G(hould instead use a simple test for size:)
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(if \(@an_array\) { print "has array elements\\n" })152 84 Q
(if \(%a_hash\))152 96 Q 6({p)18 G(rint "has hash members\\n")-6 E(})18
E F0 .625(When used on a hash element, it tells you whether the v)128
114 R .625(alue is de\214ned, not whether the k)-.25 F .924 -.15(ey ex)
-.1 H .624(ists in).15 F(the hash.)128 126 Q(Use `)5 E(`e)-.74 E(xists')
-.15 E 2.5('f)-.74 G(or the latter purpose.)-2.5 E(Examples:)128 144 Q
F1(print if defined $switch{D};)152 162 Q
(print "$val\\n" while defined\($val = pop\(@ary\)\);)152 174 Q
(die "Can\010t readlink $sym: $!")152 186 Q
(unless defined\($value = readlink $sym\);)176 198 Q
(sub foo { defined &$bar ? &$bar\(@_\) : die "No bar"; })152 210 Q
($debugging = 0 unless defined $debugging;)152 222 Q F0 2.717(Note: Man)
128 240 R 2.717(yf)-.15 G .217(olks tend to o)-2.717 F -.15(ve)-.15 G
(ruse).15 E F1(defined)2.717 E F0 .218(and are then surprised to disco)
2.718 F -.15(ve)-.15 G 2.718(rt).15 G .218(hat the number)-2.718 F F1(0)
2.718 E F0(and)2.718 E F1("")128 252 Q F0
(\(the zero-length string\) are, in f)2.5 E(act, de\214ned v)-.1 E 2.5
(alues. F)-.25 F(or e)-.15 E(xample, if you say)-.15 E F1
("ab" =~ /a\(.*\)b/;)152 270 Q F0 .514(The pattern match succeeds and)
128 288 R F1($1)3.013 E F0 .513(is de\214ned, although it matched `)
3.013 F(`nothing')-.74 E 3.013('. It)-.74 F(didn')3.013 E 3.013(tr)-.18
G .513(eally f)-3.013 F .513(ail to)-.1 F .988(match an)128 300 R 3.488
(ything. Rather)-.15 F 3.488(,i)-.4 G 3.488(tm)-3.488 G .989
(atched something that happened to be zero characters long.)-3.488 F
.989(This is all)5.989 F -.15(ve)128 312 S 1.11(ry abo).15 F -.15(ve)
-.15 G 1.11(-board and honest.).15 F 1.11
(When a function returns an unde\214ned v)6.11 F 1.11(alue, it')-.25 F
3.61(sa)-.55 G 3.61(na)-3.61 G 1.11(dmission that it)-3.61 F(couldn')128
324 Q 2.605(tg)-.18 G -2.15 -.25(iv e)-2.605 H .105
(you an honest answer)2.855 F 5.105(.S)-.55 G 2.605(oy)-5.105 G .105
(ou should use)-2.605 F F1(defined)2.605 E F0 .106
(only when questioning the inte)2.606 F(grity)-.15 E(of what you')128
336 Q(re trying to do.)-.5 E(At other times, a simple comparison to)5 E
F1(0)2.5 E F0(or)2.5 E F1("")2.5 E F0(is what you w)2.5 E(ant.)-.1 E
(See also `)128 354 Q -1.95(`undef ')-.74 F(', `)-.74 E(`e)-.74 E
(xists')-.15 E(', `)-.74 E -1.95(`ref ')-.74 F('.)-.74 E(delete)108
370.8 Q/F2 9/Times-Roman@0 SF(EXPR)2.5 E F0(Gi)128 382.8 Q -.15(ve)-.25
G 4.904(na).15 G 4.904(ne)-4.904 G 2.404
(xpression that speci\214es an element or slice of a hash,)-5.054 F F1
(delete)4.904 E F0 2.404(deletes the speci\214ed)4.904 F .312
(elements from that hash so that)128 394.8 R/F3 10/Times-Italic@0 SF -.2
(ex)2.812 G(ists\(\)).2 E F0 .312
(on that element no longer returns true.)2.812 F .313
(Setting a hash element)5.313 F(to the unde\214ned v)128 406.8 Q
(alue does not remo)-.25 E .3 -.15(ve i)-.15 H(ts k).15 E -.15(ey)-.1 G
2.5(,b)-.5 G(ut deleting it does; see `)-2.7 E(`e)-.74 E(xists')-.15 E
('.)-.74 E 1.493(In list conte)128 424.8 R 1.493(xt, returns the v)-.15
F 1.493(alue or v)-.25 F 1.492
(alues deleted, or the last such element in scalar conte)-.25 F 3.992
(xt. The)-.15 F .262(return list')128 436.8 R 2.762(sl)-.55 G .263
(ength al)-2.762 F -.1(wa)-.1 G .263(ys matches that of the ar).1 F .263
(gument list: deleting non-e)-.18 F .263(xistent elements returns the)
-.15 F(unde\214ned v)128 448.8 Q(alue in their corresponding positions.)
-.25 E F3(delete\(\))128 466.8 Q F0 .213
(may also be used on arrays and array slices, b)2.714 F .213
(ut its beha)-.2 F .213(vior is less straightforw)-.2 F 2.713
(ard. Although)-.1 F F3 -.2(ex)128 478.8 S(ists\(\)).2 E F0 .706
(will return f)3.206 F .706
(alse for deleted entries, deleting array elements ne)-.1 F -.15(ve)-.25
G 3.207(rc).15 G .707(hanges indices of e)-3.207 F(xisting)-.15 E -.25
(va)128 490.8 S .584(lues; use).25 F F3(shift\(\))3.084 E F0(or)3.084 E
F3(splice\(\))3.084 E F0 .584(for that.)3.084 F(Ho)5.584 E(we)-.25 E
-.15(ve)-.25 G 1.384 -.4(r, i).15 H 3.084(fa).4 G .584
(ll deleted elements f)-3.084 F .583(all at the end of an array)-.1 F
3.083(,t)-.65 G(he)-3.083 E(array')128 502.8 Q 2.709(ss)-.55 G .209(ize\
 shrinks to the position of the highest element that still tests true f\
or)-2.709 F F3 -.2(ex)2.709 G(ists\(\)).2 E F0 2.709(,o)C 2.709(rt)
-2.709 G 2.709(o0i)-2.709 G 2.709(fn)-2.709 G(one)-2.709 E(do.)128 514.8
Q/F4 9/Times-Bold@0 SF -1.08(WA)128 532.8 S(RNING:)1.08 E F0 .011
(Calling delete on array v)2.512 F .011(alues is deprecated and lik)-.25
F .011(ely to be remo)-.1 F -.15(ve)-.15 G 2.511(di).15 G 2.511(naf)
-2.511 G .011(uture v)-2.511 F .011(ersion of)-.15 F(Perl.)128 544.8 Q
.947(Deleting from)128 562.8 R F1(%ENV)3.447 E F0 .947
(modi\214es the en)3.447 F 3.447(vironment. Deleting)-.4 F .947
(from a hash tied to a)3.447 F F2(DBM)3.448 E F0 .948
(\214le deletes the)3.448 F .47(entry from the)128 574.8 R F2(DBM)2.97 E
F0 2.97(\214le. Deleting)2.97 F .47(from a)2.97 F F1(tied)2.97 E F0 .47
(hash or array may not necessarily return an)2.97 F .469(ything; it)-.15
F 1.092(depends on the implementation of the)128 586.8 R F1(tied)3.592 E
F0(package')3.592 E(s)-.55 E F2(DELETE)3.592 E F0 1.092
(method, which may do whate)3.592 F -.15(ve)-.25 G 3.592(ri).15 G(t)
-3.592 E(pleases.)128 598.8 Q(The)128 616.8 Q F1 .762(delete local EXPR)
3.262 F F0 .762
(construct localizes the deletion to the current block at run time.)
3.262 F(Until)5.762 E 1.99(the block e)128 628.8 R 1.991
(xits, elements locally deleted temporarily no longer e)-.15 F 4.491
(xist. See)-.15 F -.74(``)4.491 G 1.991(Localized deletion of).74 F
(elements of composite types')128 640.8 Q 2.5('i)-.74 G 2.5(np)-2.5 G
(erlsub)-2.5 E(.)-.4 E F1(%hash = \(foo => 11, bar => 22, baz => 33\);)
152 658.8 Q($scalar = delete $hash{foo};)152 670.8 Q 6(#$)78 G
(scalar is 11)-6 E($scalar = delete @hash{qw\(foo bar\)};)152 682.8 Q 6
(#$)30 G(scalar is 22)-6 E 6(@array =)152 694.8 R
(delete @hash{qw\(foo bar baz\)}; # @array)6 E(is \(undef,undef,33\))12
E F0(The follo)128 712.8 Q(wing \(inef)-.25 E
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(foreach $key \(keys %HASH\) {)152 84 Q(delete $HASH{$key};)176 96 Q(})
152 108 Q(foreach $index \(0 .. $#ARRAY\) {)152 132 Q
(delete $ARRAY[$index];)176 144 Q(})152 156 Q F0(And so do these:)128
174 Q F1(delete @HASH{keys %HASH};)152 192 Q
(delete @ARRAY[0 .. $#ARRAY];)152 216 Q F0 1.59(But both are slo)128 234
R 1.589(wer than assigning the empty list or unde\214ning)-.25 F F1
(%HASH)4.089 E F0(or)4.089 E F1(@ARRAY)4.089 E F0 4.089(,w)C 1.589
(hich is the)-4.089 F(customary w)128 246 Q(ay to empty out an aggre)-.1
E -.05(ga)-.15 G(te:).05 E F1(%HASH = \(\);)152 264 Q 6(#c)30 G
(ompletely empty %HASH)-6 E(undef %HASH;)152 276 Q 6(#f)24 G
(orget %HASH ever existed)-6 E(@ARRAY = \(\);)152 300 Q 6(#c)24 G
(ompletely empty @ARRAY)-6 E(undef @ARRAY;)152 312 Q 6(#f)18 G
(orget @ARRAY ever existed)-6 E F0(The)128 330 Q/F2 9/Times-Roman@0 SF
(EXPR)4.291 E F0 1.791(can be arbitrarily complicated pro)4.291 F 1.791
(vided its \214nal operation is an element or slice of an)-.15 F(aggre)
128 342 Q -.05(ga)-.15 G(te:).05 E F1(delete $ref\255>[$x][$y]{$key};)
152 360 Q(delete @{$ref\255>[$x][$y]}{$key1, $key2, @morekeys};)152 372
Q(delete $ref\255>[$x][$y][$index];)152 396 Q
(delete @{$ref\255>[$x][$y]}[$index1, $index2, @moreindices];)152 408 Q
F0(die)108 424.8 Q F2(LIST)2.5 E F1(die)128 436.8 Q F0 2.093
(raises an e)4.593 F 2.093(xception. Inside an)-.15 F F1(eval)4.593 E F0
2.092(the error message is stuf)4.592 F 2.092(fed into)-.25 F F1($@)
4.592 E F0 2.092(and the)4.592 F F1(eval)4.592 E F0(is)4.592 E 1.748
(terminated with the unde\214ned v)128 448.8 R 4.248(alue. If)-.25 F
1.748(the e)4.248 F 1.748(xception is outside of all enclosing)-.15 F F1
(eval)4.248 E F0 1.748(s, then the)B 1.078(uncaught e)128 460.8 R 1.078
(xception prints)-.15 F F2(LIST)3.577 E F0(to)3.577 E F1(STDERR)3.577 E
F0 1.077(and e)3.577 F 1.077(xits with a non-zero v)-.15 F 1.077
(alue. If you need to e)-.25 F 1.077(xit the)-.15 F
(process with a speci\214c e)128 472.8 Q(xit code, see `)-.15 E(`e)-.74
E(xit')-.15 E('.)-.74 E(Equi)128 490.8 Q -.25(va)-.25 G(lent e).25 E
(xamples:)-.15 E F1(die "Can\010t cd to spool: $!\\n" unless chdir \010\
/usr/spool/news\010;)152 508.8 Q
(chdir \010/usr/spool/news\010 or die "Can\010t cd to spool: $!\\n")152
520.8 Q F0 1.197(If the last element of)128 538.8 R F2(LIST)3.697 E F0
1.197(does not end in a ne)3.697 F 1.198
(wline, the current script line number and input line)-.25 F .756
(number \(if an)128 550.8 R .756(y\) are also printed, and a ne)-.15 F
.755(wline is supplied.)-.25 F .755(Note that the `)5.755 F .755
(`input line number')-.74 F 3.255('\()-.74 G(also)-3.255 E(kno)128 562.8
Q .872(wn as `)-.25 F(`chunk')-.74 E .873('\) is subject to whate)-.74 F
-.15(ve)-.25 G 3.373(rn).15 G .873(otion of `)-3.373 F(`line')-.74 E
3.373('h)-.74 G .873(appens to be currently in ef)-3.373 F .873
(fect, and is)-.25 F(also a)128 574.8 Q -.25(va)-.2 G
(ilable as the special v).25 E(ariable)-.25 E F1($.)2.5 E F0 5(.S)C
(ee `)-5 E(`$/')-.74 E 2.5('i)-.74 G 2.5(np)-2.5 G(erlv)-2.5 E(ar and `)
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E(.)-.55 E .484(Hint: sometimes appending)128 592.8 R F1 .484
(", stopped")2.984 F F0 .483(to your message will cause it to mak)2.984
F 2.983(eb)-.1 G .483(etter sense when)-2.983 F(the string)128 604.8 Q
F1("at foo line 123")2.5 E F0(is appended.)2.5 E
(Suppose you are running script `)5 E(`canasta')-.74 E('.)-.74 E F1
(die "/etc/games is no good";)152 622.8 Q
(die "/etc/games is no good, stopped";)152 634.8 Q F0(produce, respecti)
128 652.8 Q -.15(ve)-.25 G(ly).15 E F1
(/etc/games is no good at canasta line 123.)152 670.8 Q
(/etc/games is no good, stopped at canasta line 123.)152 682.8 Q F0 .937
(If the output is empty and)128 700.8 R F1($@)3.437 E F0 .937
(already contains a v)3.437 F .937(alue \(typically from a pre)-.25 F
.938(vious e)-.25 F -.25(va)-.25 G .938(l\) that v).25 F .938(alue is)
-.25 F(reused after appending)128 712.8 Q F1("\\t...propagated")2.5 E F0
5(.T)C(his is useful for propag)-5 E(ating e)-.05 E(xceptions:)-.15 E
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(eval { ... };)152 84 Q(die unless $@ =~ /Expected exception/;)152 96 Q
F0 1.924(If the output is empty and)128 114 R F1($@)4.424 E F0 1.924
(contains an object reference that has a)4.424 F F1(PROPAGATE)4.423 E F0
1.923(method, that)4.423 F .692(method will be called with additional \
\214le and line number parameters.)128 126 R .692(The return v)5.692 F
.692(alue replaces the)-.25 F -.25(va)128 138 S .368(lue in).25 F F1($@)
2.868 E F0 5.368(;i)C .368(.e., as if)-5.368 F F1 .367
($@ = eval { $@\255>PROPAGATE\(_)2.867 F -4.334(_FILE_ _,)1.666 F 1.666
(__)6.367 G -4.334(LINE_ _\))-1.666 F(};)6.367 E F0(were)2.867 E
(called.)128 150 Q(If)128 168 Q F1($@)2.5 E F0(is empty then the string)
2.5 E F1("Died")2.5 E F0(is used.)2.5 E .601(If an uncaught e)128 186 R
.601(xception results in interpreter e)-.15 F .601(xit, the e)-.15 F
.601(xit code is determined from the v)-.15 F .602(alues of)-.25 F F1
($!)3.102 E F0(and)128 198 Q F1($?)2.5 E F0(with this pseudocode:)2.5 E
F1(exit $! if $!;)152 216 Q 6(#e)84 G(rrno)-6 E
(exit $? >> 8 if $? >> 8;)152 228 Q 6(#c)24 G(hild exit status)-6 E
(exit 255;)152 240 Q 6(#l)114 G(ast resort)-6 E F0 .502
(The intent is to squeeze as much possible information about the lik)128
258 R .501(ely cause into the limited space of)-.1 F .249(the system e)
128 270 R .249(xit code. Ho)-.15 F(we)-.25 E -.15(ve)-.25 G 1.049 -.4
(r, a).15 H(s).4 E F1($!)2.749 E F0 .249(is the v)2.749 F .249
(alue of C')-.25 F(s)-.55 E F1(errno)2.75 E F0 2.75(,w)C .25
(hich can be set by an)-2.75 F 2.75(ys)-.15 G .25(ystem call,)-2.75 F
.323(this means that the v)128 282 R .323(alue of the e)-.25 F .323
(xit code used by)-.15 F F1(die)2.823 E F0 .322
(can be non-predictable, so should not be relied)2.823 F
(upon, other than to be non-zero.)128 294 Q -1.1(Yo)128 312 S 3.081(uc)
1.1 G .581(an also call)-3.081 F F1(die)3.081 E F0 .581
(with a reference ar)3.081 F .581
(gument, and if this is trapped within an)-.18 F F1(eval)3.081 E F0(,)A
F1($@)3.082 E F0(contains)3.082 E .973(that reference.)128 324 R .973
(This permits more elaborate e)5.973 F .972
(xception handling using objects that maintain arbitrary)-.15 F .335
(state about the e)128 336 R 2.835(xception. Such)-.15 F 2.835(as)2.835
G .335(cheme is sometimes preferable to matching particular string v)
-2.835 F(alues)-.25 E(of)128 348 Q F1($@)2.788 E F0 .288(with re)2.788 F
.288(gular e)-.15 F 2.788(xpressions. Because)-.15 F F1($@)2.788 E F0
.288(is a global v)2.788 F .288(ariable and)-.25 F F1(eval)2.787 E F0
.287(may be used within object)2.787 F .58
(implementations, be careful that analyzing the error object doesn')128
360 R 3.08(tr)-.18 G .58(eplace the reference in the global)-3.08 F -.25
(va)128 372 S 4.551(riable. It').25 F 4.551(se)-.55 G 2.051
(asiest to mak)-4.551 F 4.551(eal)-.1 G 2.051(ocal cop)-4.551 F 4.551
(yo)-.1 G 4.551(ft)-4.551 G 2.05(he reference before an)-4.551 F 4.55
(ym)-.15 G 4.55(anipulations. Here')-4.55 F 4.55(sa)-.55 G(n)-4.55 E
-.15(ex)128 384 S(ample:).15 E F1(use Scalar::Util "blessed";)152 402 Q
(eval { ... ; die Some::Module::Exception\255>new\( FOO => "bar" \) };)
152 426 Q(if \(my $ev_err = $@\) {)152 438 Q(if \(blessed\($ev_err\) &&\
 $ev_err\255>isa\("Some::Module::Exception"\)\) {)176 450 Q 6(#h)200 462
S(andle Some::Module::Exception)-6 E(})176 474 Q(else {)176 486 Q 6(#h)
200 498 S(andle all other possible exceptions)-6 E(})176 510 Q(})152 522
Q F0 .21(Because Perl stringi\214es uncaught e)128 540 R .211
(xception messages before display)-.15 F 2.711(,y)-.65 G(ou')-2.711 E
.211(ll probably w)-.1 F .211(ant to o)-.1 F -.15(ve)-.15 G(rload).15 E
(stringi\214cation operations on e)128 552 Q(xception objects.)-.15 E
(See o)5 E -.15(ve)-.15 G(rload for details about that.).15 E -1.1(Yo)
128 570 S 5.767(uc)1.1 G 3.266
(an arrange for a callback to be run just before the)-5.767 F F1(die)
5.766 E F0 3.266(does its deed, by setting the)5.766 F F1 -4.334
($SIG{_ _DIE_ _})128 582 R F0 3.952(hook. The)3.952 F 1.453
(associated handler is called with the error te)3.952 F 1.453
(xt and can change the)-.15 F .288
(error message, if it sees \214t, by calling)128 594 R F1(die)2.788 E F0
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(This form of subroutine call is deprecated.)128 178.8 R F1(SUBR)6.126 E
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(Practical hint: you almost ne)128 282 R -.15(ve)-.25 G 3.143(rn).15 G
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(un out of data or encounter an error)-2.5 E(.)-.55 E -.25(eva)108 310.8
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(xpression \(which is itself determined within scalar conte)-.15 F 1.222
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F2($?)2.5 E F0(to a non-zero v)2.5 E(alue indicating f)-.25 E(ailure.)
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2.5 E F0(blocks, nor will it in)2.5 E -.2(vo)-.4 G -.1(ke).2 G F2
(DESTROY)2.6 E F0(methods on your objects.)2.5 E -.15(ex)108 304.8 S
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E(alue is unde\214ned.)-.25 E F2(print "Exists\\n")152 346.8 Q
(if exists $hash{$key};)24 E(print "Defined\\n")152 358.8 Q
(if defined $hash{$key};)18 E(print "True\\n")152 370.8 Q
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(if exists $array[$index];)24 E(print "Defined\\n")152 442.8 Q
(if defined $array[$index];)18 E(print "True\\n")152 454.8 Q
(if $array[$index];)36 E F0 3.488(Ah)128 472.8 S .988
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550.8 Q(.)-.4 E F2(print "Exists\\n")152 568.8 Q(if exists &subroutine;)
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(if \(exists $ref\255>{A}\255>{B}\255>{$key}\))152 628.8 Q 6({})12 G
(if \(exists $hash{A}{B}{$key}\))152 640.8 Q 6({})42 G
(if \(exists $ref\255>{A}\255>{B}\255>[$ix]\))152 664.8 Q 6({})18 G
(if \(exists $hash{A}{B}[$ix]\))152 676.8 Q 6({})48 G
(if \(exists &{$ref\255>{A}{B}{$key}}\))152 700.8 Q 6({})18 G F0 2.423
(Although the mostly deeply nested array or hash will not spring into e)
128 718.8 R 2.423(xistence just because its)-.15 F -.15(ex)128 730.8 S
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(vi\214cation in what does not at \214rst)-.25 F 1.666<8a6f>1.666 G
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(alue conte)-.25 E(xt may be \214x)-.15 E(ed in a future release.)-.15 E
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186 Q(gument to)-.18 E/F2 10/Times-Italic@0 SF -.2(ex)2.5 G(ists\(\)).2
E F0(is an error)2.5 E(.)-.55 E F1(exists &sub;)152 204 Q 6(#O)24 G(K)-6
E(exists &sub\(\);)152 216 Q 6(#E)12 G(rror)-6 E F0 -.15(ex)108 232.8 S
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E(Ev)128 244.8 Q(aluates)-.25 E F3(EXPR)2.5 E F0(and e)2.5 E
(xits immediately with that v)-.15 E 7.5(alue. Example:)-.25 F F1
($ans = <STDIN>;)152 262.8 Q(exit 0 if $ans =~ /^[Xx]/;)152 274.8 Q F0
1.285(See also)128 292.8 R F1(die)3.785 E F0 6.285(.I)C(f)-6.285 E F3
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(0)3.785 E F0 3.785(status. The)3.785 F 1.284(only uni)3.785 F -.15(ve)
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128 304.8 Q F0(are)3.699 E F1(0)3.699 E F0 1.199(for success and)3.699 F
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2.786 F -.15(ve)-.25 G .287(red, b).15 F .287(ut that')-.2 F 2.787(sn)
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2.5 E F0(instead, which can be trapped by an)2.5 E F1(eval)2.5 E F0(.)A
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(xit status by modifying)-.15 F F1($?)128 424.8 Q F0 4.544(.I)C 4.544
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(\(the natural log)2.5 E(arithm base\) to the po)-.05 E(wer of)-.25 E F3
(EXPR)2.5 E F0 5(.I)C(f)-5 E F3(EXPR)2.5 E F0(is omitted, gi)2.5 E -.15
(ve)-.25 G(s).15 E F1(exp\($_\))2.5 E F0(.)A(fcntl)108 482.4 Q F3
(FILEHANDLE)2.5 E F0(,FUNCTION,SCALAR)A(Implements the)128 494.4 Q F2
(fcntl)2.5 E F0(\(2\) function.)1.666 E -1.1(Yo)5 G(u')1.1 E
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(use Fcntl;)152 512.4 Q F0 1.342
(\214rst to get the correct constant de\214nitions.)128 530.4 R(Ar)6.342
E 1.342(gument processing and v)-.18 F 1.342(alue returned w)-.25 F
1.343(ork just lik)-.1 F(e)-.1 E F1(ioctl)128 542.4 Q F0(belo)2.5 E 3.8
-.65(w. F)-.25 H(or e).5 E(xample:)-.15 E F1(use Fcntl;)152 560.4 Q
(fcntl\($filehandle, F_GETFL, $packed_return_buffer\))152 572.4 Q
(or die "can\010t fcntl F_GETFL: $!";)176 584.4 Q F0 -1.1(Yo)128 602.4 S
3.3(ud)1.1 G(on')-3.3 E 3.3(th)-.18 G -2.25 -.2(av e)-3.3 H .8
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(or die "Can\010t get flags for the socket: $!\\n";)224 84 Q
($flags = fcntl\(REMOTE, F_SETFL, $flags | O_NONBLOCK\))152 108 Q
(or die "Can\010t set flags for the socket: $!\\n";)224 120 Q F0
(\214leno)108 136.8 Q/F2 9/Times-Roman@0 SF(FILEHANDLE)2.5 E F0 .138(Re\
turns the \214le descriptor for a \214lehandle, or unde\214ned if the \
\214lehandle is not open.)128 148.8 R .138(If there is no real)5.138 F
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(l, as can happen with \214lehandles connected to memory objects via).15
F F1(open)3.022 E F0(with a reference for the third ar)128 172.8 Q
(gument, \2551 is returned.)-.18 E 3.204
(This is mainly useful for constructing bitmaps for)128 190.8 R F1
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(\215ock)108 291.6 Q F2(FILEHANDLE)2.5 E F0(,OPERA)A(TION)-1.11 E(Calls)
128 303.6 Q/F3 10/Times-Italic@0 SF(\215oc)4.247 E(k)-.2 E F0 1.747
(\(2\), or an emulation of it, on)1.666 F F2(FILEHANDLE)4.246 E F0 6.746
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(ut)-.2 E(of)128 381.6 Q 1.93(fer fe)-.25 F 1.93(wer guarantees.)-.25 F
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3.049(ss)-.55 G .549
(peci\214c documentation, and your system-speci\214c local)-3.049 F
1.622(manpages for details.)128 405.6 R(It')6.622 E 4.122(sb)-.55 G
1.622(est to assume traditional beha)-4.122 F 1.622(vior if you')-.2 F
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R 3.366(re not, you should as al)-.5 F -.1(wa)-.1 G 3.365
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(LOCK_SH)2.692 E F0(,)A F2(LOCK_EX)2.692 E F0 2.692(,o)C(r)-2.692 E F2
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Q F2(LOCK_NB)3.787 E F0 1.287(is bitwise-or'ed with)3.787 F F2(LOCK_SH)
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(flock)3.786 E F0 1.286(returns immediately rather)3.786 F
(than blocking w)128 519.6 Q
(aiting for the lock; check the return status to see if you got it.)-.1
E 4.885 -.8(To a)128 537.6 T -.2(vo).6 G 3.285
(id the possibility of miscoordination, Perl no).2 F 5.785<778d>-.25 G
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(vide shared locks, and it requires that)-.15 F F2(FILEHANDLE)128 579.6
Q F0 .883(be open with write intent.)3.383 F .883
(These are the semantics that)5.883 F F3(loc)3.383 E(kf)-.2 E F0 .884
(\(3\) implements.)1.666 F .884(Most if)5.884 F 1.407
(not all systems implement)128 591.6 R F3(loc)3.907 E(kf)-.2 E F0 1.407
(\(3\) in terms of)1.666 F F3(fcntl)3.907 E F0 1.407
(\(2\) locking, though, so the dif)1.666 F 1.407(fering semantics)-.25 F
(shouldn')128 603.6 Q 2.5(tb)-.18 G(ite too man)-2.5 E 2.5(yp)-.15 G
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(\(3\) requires that)1.666 F F2(FILEHANDLE)2.684 E F0 .184
(be open with read intent to use)2.684 F F2(LOCK_SH)128 633.6 Q F0
(and requires that it be open with write intent to use)2.5 E F2(LOCK_EX)
2.5 E F0(.)A .763(Note also that some v)128 651.6 R .763(ersions of)-.15
F F1(flock)3.263 E F0 .763(cannot lock things o)3.263 F -.15(ve)-.15 G
3.263(rt).15 G .763(he netw)-3.263 F .763(ork; you w)-.1 F .763
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(\(2\)\255based emulation, by passing the switch)1.666 F F1
(\255Ud_flock)128 687.6 Q F0(to the)2.5 E F3(Con\214gur)2.5 E(e)-.37 E
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(use Fcntl qw\(:flock SEEK_END\); # import LOCK_* and SEEK_END constant\
s)152 84 Q(sub lock {)152 108 Q(my \($fh\) = @_;)176 120 Q
(flock\($fh, LOCK_EX\) or die "Cannot lock mailbox \255 $!\\n";)176 132
Q 6(#a)176 156 S(nd, in case someone appended while we were waiting...)
-6 E(seek\($fh, 0, SEEK_END\) or die "Cannot seek \255 $!\\n";)176 168 Q
(})152 180 Q(sub unlock {)152 204 Q(my \($fh\) = @_;)176 216 Q
(flock\($fh, LOCK_UN\) or die "Cannot unlock mailbox \255 $!\\n";)176
228 Q(})152 240 Q
(open\(my $mbox, ">>", "/usr/spool/mail/$ENV{\010USER\010}"\))152 264 Q
(or die "Can\010t open mailbox: $!";)176 276 Q(lock\($mbox\);)152 300 Q
(print $mbox $msg,"\\n\\n";)152 312 Q(unlock\($mbox\);)152 324 Q F0 .212
(On systems that support a real)128 342 R/F2 10/Times-Italic@0 SF
(\215oc)2.712 E(k)-.2 E F0 .212(\(2\), locks are inherited across)1.666
F F2(fork\(\))2.712 E F0 .212(calls, whereas those that must)2.712 F
1.471(resort to the more capricious)128 354 R F2(fcntl)3.97 E F0 1.47
(\(2\) function lose their locks, making it seriously harder to write)
1.666 F(serv)128 366 Q(ers.)-.15 E(See also DB_File for other)128 384 Q
F2(\215oc)2.5 E(k\(\))-.2 E F0 -.15(ex)2.5 G(amples.).15 E(fork)108
400.8 Q 1.024(Does a)128 412.8 R F2(fork)3.524 E F0 1.024
(\(2\) system call to create a ne)1.666 F 3.525(wp)-.25 G 1.025
(rocess running the same program at the same point.)-3.525 F(It)6.025 E
.115(returns the child pid to the parent process,)128 424.8 R F1(0)2.614
E F0 .114(to the child process, or)2.614 F F1(undef)2.614 E F0 .114
(if the fork is unsuccessful.)2.614 F .057(File descriptors \(and somet\
imes locks on those descriptors\) are shared, while e)128 436.8 R -.15
(ve)-.25 G .058(rything else is copied.).15 F 2.695
(On most systems supporting)128 448.8 R F2(fork\(\))5.195 E F0 5.195(,g)
C 2.695(reat care has gone into making it e)-5.195 F 2.695(xtremely ef)
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(ve)-.15 G 2.5(rt).15 G(he last fe)-2.5 E 2.5(wd)-.25 G(ecades.)-2.5 E
(Be)128 490.8 Q 2.033(ginning with v5.6.0, Perl attempts to \215ush all\
 \214les opened for output before forking the child)-.15 F .324
(process, b)128 502.8 R .324
(ut this may not be supported on some platforms \(see perlport\).)-.2 F
1.925 -.8(To b)5.325 H 2.825(es).8 G .325(afe, you may need to)-2.825 F
(set)128 514.8 Q F1($|)2.653 E F0(\($A)2.653 E(UT)-.55 E .152
(OFLUSH in English\) or call the)-.18 F F1(autoflush\(\))2.652 E F0 .152
(method of)2.652 F F1(IO::Handle)2.652 E F0 .152(on an)2.652 F 2.652(yo)
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.402(without e)2.902 F -.15(ve)-.25 G 2.902(rw).15 G .403
(aiting on your children, you will accumulate zombies.)-3.002 F .403
(On some systems,)5.403 F 1.028(you can a)128 556.8 R -.2(vo)-.2 G 1.028
(id this by setting).2 F F1($SIG{CHLD})3.528 E F0(to)3.528 E F1
("IGNORE")3.528 E F0 6.028(.S)C 1.028(ee also perlipc for more e)-6.028
F 1.028(xamples of)-.15 F(forking and reaping morib)128 568.8 Q
(und children.)-.2 E .154(Note that if your fork)128 586.8 R .155
(ed child inherits system \214le descriptors lik)-.1 F(e)-.1 E/F3 9
/Times-Roman@0 SF(STDIN)2.655 E F0(and)2.655 E F3(STDOUT)2.655 E F0 .155
(that are actually)2.655 F .476(connected by a pipe or sock)128 598.8 R
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(ou e)-2.976 F .476(xit, then the remote serv)-.15 F .476
(er \(such as, say)-.15 F 2.976(,a)-.65 G F3(CGI)-.001 E F0 .475
(script or a)2.975 F .17
(backgrounded job launched from a remote shell\) w)128 610.8 R(on')-.1 E
2.671(tt)-.18 G .171(hink you')-2.671 F .171(re done.)-.5 F -1.1(Yo)
5.171 G 2.671(us)1.1 G .171(hould reopen those to)-2.671 F F2(/de)128
622.8 Q(v/null)-.15 E F0(if it')2.5 E 2.5(sa)-.55 G .3 -.15(ny i)-2.5 H
(ssue.).15 E(format)108 639.6 Q(Declare a picture format for use by the)
128 651.6 Q F1(write)2.5 E F0 2.5(function. F)2.5 F(or e)-.15 E(xample:)
-.15 E F1(format Something =)152 669.6 Q(Test: @<<<<<<<< @||||| @>>>>>)
176 681.6 Q 24($str, $%,)212 693.6 R(\010$\010 . int\($num\))24 E(.)152
705.6 Q($str = "widget";)152 729.6 Q F0(perl v5.14.2)72 768 Q 198.17
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(write;)152 108 Q F0(See perlform for man)128 126 Q 2.5(yd)-.15 G
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(accumulator)128 178.8 Q(,)-.4 E F1($^A)2.835 E F0(\(or)2.835 E F1
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(is done, the contents)2.834 F(of)128 190.8 Q F1($^A)3.066 E F0 .567
(are written to some \214lehandle.)3.066 F -1.1(Yo)5.567 G 3.067(uc)1.1
G .567(ould also read)-3.067 F F1($^A)3.067 E F0 .567(and then set)3.067
F F1($^A)3.067 E F0 .567(back to)3.067 F F1("")3.067 E F0 5.567(.N)C
(ote)-5.567 E 1.898(that a format typically does one)128 202.8 R F1
(formline)4.397 E F0 1.897(per line of form, b)4.397 F 1.897(ut the)-.2
F F1(formline)4.397 E F0 1.897(function itself)4.397 F(doesn')128 214.8
Q 2.761(tc)-.18 G .261(are ho)-2.761 F 2.761(wm)-.25 G(an)-2.761 E 2.761
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(PICTURE)2.761 E F0 5.261(.T)C .261(his means that the)-5.261 F F1(~)
2.761 E F0(and)2.761 E F1(~~)2.761 E F0(tok)2.761 E(ens)-.1 E 2.263
(treat the entire)128 226.8 R F2(PICTURE)4.763 E F0 2.263
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(implement a single record format, just lik)128 238.8 Q 2.5(et)-.1 G(he)
-2.5 E F1(format)2.5 E F0(compiler)2.5 E(.)-.55 E .514
(Be careful if you put double quotes around the picture, because an)128
256.8 R F1(@)3.015 E F0 .515(character may be tak)3.015 F .515
(en to mean)-.1 F(the be)128 268.8 Q(ginning of an array name.)-.15 E F1
(formline)5 E F0(al)2.5 E -.1(wa)-.1 G(ys returns true.).1 E
(See perlform for other e)5 E(xamples.)-.15 E .653
(If you are trying to use this instead of)128 286.8 R F1(write)3.153 E
F0 .653(to capture the output, you may \214nd it easier to open a)3.153
F(\214lehandle to a scalar \()128 298.8 Q F1(open $fh, ">", \\$output)A
F0 2.5(\)a)C(nd write to that instead.)-2.5 E(getc)108 315.6 Q F2
(FILEHANDLE)2.5 E F0(getc)108 327.6 Q .456(Returns the ne)128 339.6 R
.457(xt character from the input \214le attached to)-.15 F F2
(FILEHANDLE)2.957 E F0 2.957(,o)C 2.957(rt)-2.957 G .457
(he unde\214ned v)-2.957 F .457(alue at end)-.25 F 1.001
(of \214le or if there w)128 351.6 R 1.001
(as an error \(in the latter case)-.1 F F1($!)3.501 E F0 1.001
(is set\).)3.501 F(If)6.001 E F2(FILEHANDLE)3.501 E F0 1.001
(is omitted, reads from)3.501 F F2(STDIN)128 363.6 Q F0 7.826(.T)C 2.827
(his is not particularly ef)-7.826 F 5.327(\214cient. Ho)-.25 F(we)-.25
E -.15(ve)-.25 G 3.627 -.4(r, i).15 H 5.327(tc).4 G 2.827
(annot be used by itself to fetch single)-5.327 F(characters without w)
128 375.6 Q(aiting for the user to hit enter)-.1 E 5(.F)-.55 G
(or that, try something more lik)-5.15 E(e:)-.1 E F1
(if \($BSD_STYLE\) {)152 393.6 Q
(system "stty cbreak </dev/tty >/dev/tty 2>&1";)176 405.6 Q(})152 417.6
Q(else {)152 429.6 Q
(system "stty", \010\255icanon\010, \010eol\010, "\\001";)176 441.6 Q(})
152 453.6 Q($key = getc\(STDIN\);)152 477.6 Q(if \($BSD_STYLE\) {)152
501.6 Q(system "stty \255cbreak </dev/tty >/dev/tty 2>&1";)176 513.6 Q
(})152 525.6 Q(else {)152 537.6 Q(system \010stty\010, \010icanon\010, \
\010eol\010, \010^@\010; # ASCII NUL)176 549.6 Q(})152 561.6 Q
(print "\\n";)152 573.6 Q F0(Determination of whether)128 591.6 Q F1
($BSD_STYLE)2.5 E F0(should be set is left as an e)2.5 E -.15(xe)-.15 G
(rcise to the reader).15 E(.)-.55 E(The)128 609.6 Q F1(POSIX::getattr)
7.002 E F0 4.502
(function can do this more portably on systems purporting)7.002 F F2
(POSIX)7.001 E F0 3.454(compliance. See)128 621.6 R .954(also the)3.454
F F1(Term::ReadKey)3.454 E F0 .955(module from your nearest)3.454 F F2
(CP)3.455 E(AN)-.828 E F0 .955(site; details on)3.455 F F2(CP)3.455 E
(AN)-.828 E F0(can be found under `)128 633.6 Q(`)-.74 E F2(CP)A(AN)
-.828 E F0 1.48 -.74('' i)D 2.5(np).74 G(erlmodlib)-2.5 E(.)-.4 E
(getlogin)108 650.4 Q .596(This implements the C library function of th\
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(login from)128 674.4 Q/F3 10/Times-Italic@0 SF(/etc/utmp)2.5 E F0 2.5
(,i)C 2.5(fa)-2.5 G -.15(ny)-2.5 G 5(.I)-.5 G 2.5(fi)-5 G 2.5(tr)-2.5 G
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(Do not consider)128 710.4 Q F1(getlogin)2.5 E F0
(for authentication: it is not as secure as)2.5 E F1(getpwuid)2.5 E F0
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Q/F1 9/Times-Roman@0 SF(SOCKET)2.5 E F0(Returns the pack)128 96 Q
(ed sockaddr address of the other end of the)-.1 E F1(SOCKET)2.5 E F0
(connection.)2.5 E/F2 10/Courier@0 SF(use Socket;)152 114 Q 18
($hersockaddr =)152 126 R(getpeername\(SOCK\);)6 E
(\($port, $iaddr\) = sockaddr_in\($hersockaddr\);)152 138 Q 18
($herhostname =)152 150 R(gethostbyaddr\($iaddr, AF_INET\);)6 E 24
($herstraddr =)152 162 R(inet_ntoa\($iaddr\);)6 E F0(getpgrp)108 178.8 Q
F1(PID)2.5 E F0 1.319
(Returns the current process group for the speci\214ed)128 190.8 R F1
(PID)3.819 E F0 6.32(.U)C 1.32(se a)-6.32 F F1(PID)3.82 E F0(of)3.82 E
F2(0)3.82 E F0 1.32(to get the current process)3.82 F 1.079
(group for the current process.)128 202.8 R -.4(Wi)6.078 G 1.078
(ll raise an e).4 F 1.078(xception if used on a machine that doesn')-.15
F 3.578(ti)-.18 G(mplement)-3.578 E/F3 10/Times-Italic@0 SF -.1(ge)128
214.8 S(tpgrp).1 E F0 3.246(\(2\). If)1.666 F F1(PID)3.246 E F0 .746
(is omitted, returns the process group of the current process.)3.246 F
.747(Note that the)5.747 F F1(POSIX)3.247 E F0 -.15(ve)128 226.8 S
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F0(ar)2.5 E(gument, so only)-.18 E F2(PID==0)2.5 E F0
(is truly portable.)2.5 E(getppid)108 243.6 Q
(Returns the process id of the parent process.)128 255.6 Q .456
(Note for Linux users: on Linux, the C functions)128 273.6 R F2
(getpid\(\))2.956 E F0(and)2.956 E F2(getppid\(\))2.955 E F0 .455
(return dif)2.955 F .455(ferent v)-.25 F(alues)-.25 E .495(from dif)128
285.6 R .495(ferent threads. In order to be portable, this beha)-.25 F
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(lf).15 G(unction)-2.996 E F2(getppid\(\))128 297.6 Q F0 5.125(,t)C
2.625(hat returns a consistent v)-5.125 F 2.624
(alue across threads. If you w)-.25 F 2.624(ant to call the underlying)
-.1 F F2(getppid\(\))128 309.6 Q F0 2.5(,y)C(ou may use the)-2.5 E F1
(CP)2.5 E(AN)-.828 E F0(module)2.5 E F2(Linux::Pid)2.5 E F0(.)A
(getpriority)108 326.4 Q F1(WHICH)2.5 E F0(,WHO)A .176
(Returns the current priority for a process, a process group, or a user)
128 338.4 R 5.176(.\()-.55 G(See)-5.176 E F2(getpriority\(2\))2.676 E F0
2.676(.\) W)B(ill)-.4 E(raise a f)128 350.4 Q(atal e)-.1 E
(xception if used on a machine that doesn')-.15 E 2.5(ti)-.18 G
(mplement)-2.5 E F3 -.1(ge)2.5 G(tpriority).1 E F0(\(2\).)1.666 E
(getpwnam)108 367.2 Q F1 -.315(NA)2.5 G(ME).315 E F0(getgrnam)108 379.2
Q F1 -.315(NA)2.5 G(ME).315 E F0(gethostbyname)108 391.2 Q F1 -.315(NA)
2.5 G(ME).315 E F0(getnetbyname)108 403.2 Q F1 -.315(NA)2.5 G(ME).315 E
F0(getprotobyname)108 415.2 Q F1 -.315(NA)2.5 G(ME).315 E F0(getpwuid)
108 427.2 Q F1(UID)2.5 E F0(getgr)108 439.2 Q(gid)-.18 E F1(GID)2.5 E F0
(getservbyname)108 451.2 Q F1 -.315(NA)2.5 G(ME).315 E F0(,PR)A -1.88
-.4(OT O)-.4 H(gethostbyaddr)108 463.2 Q F1(ADDR)2.5 E F0(,ADDR)A(TYPE)
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(getprotobynumber)108 487.2 Q F1(NUMBER)2.5 E F0(getservbyport)108 499.2
Q F1(POR)2.5 E(T)-.54 E F0(,PR)A -1.88 -.4(OT O)-.4 H(getpwent)108 511.2
Q(getgrent)108 523.2 Q(gethostent)108 535.2 Q(getnetent)108 547.2 Q
(getprotoent)108 559.2 Q(getserv)108 571.2 Q(ent)-.15 E(setpwent)108
583.2 Q(setgrent)108 595.2 Q(sethostent)108 607.2 Q F1(ST)2.5 E -.63
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(ST)2.5 E -.63 -.945(AY O)-.837 H(PEN).945 E F0(endpwent)108 655.2 Q
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(ent)-.15 E 1.084(These routines are the same as their counterparts in \
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(lues from the v).25 E(arious get routines are as follo)-.25 E(ws:)-.25
E/F1 10/Courier@0 SF(\($name,$passwd,$uid,$gid,)152 126 Q
($quota,$comment,$gcos,$dir,$shell,$expire\) = getpw*)170 138 Q
(\($name,$passwd,$gid,$members\) = getgr*)152 150 Q
(\($name,$aliases,$addrtype,$length,@addrs\) = gethost*)152 162 Q
(\($name,$aliases,$addrtype,$net\) = getnet*)152 174 Q
(\($name,$aliases,$proto\) = getproto*)152 186 Q
(\($name,$aliases,$port,$proto\) = getserv*)152 198 Q F0
(\(If the entry doesn')128 216 Q 2.5(te)-.18 G
(xist you get an empty list.\))-2.65 E 1.444(The e)128 234 R 1.444
(xact meaning of the)-.15 F F1($gcos)3.944 E F0 1.444(\214eld v)3.944 F
1.444(aries b)-.25 F 1.445
(ut it usually contains the real name of the user \(as)-.2 F 1.36(oppos\
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246 R 6.36(.B)-.55 G -2.1 -.25(ew a)-6.36 H 1.36(re, ho).25 F(we)-.25 E
-.15(ve)-.25 G 2.16 -.4(r, t).15 H 1.36(hat in).4 F(man)128 258 Q 2.813
(ys)-.15 G .314(ystem users are able to change this information and the\
refore it cannot be trusted and therefore)-2.813 F(the)128 270 Q F1
($gcos)2.659 E F0 .159(is tainted \(see perlsec\).)2.659 F(The)5.159 E
F1($passwd)2.659 E F0(and)2.659 E F1($shell)2.658 E F0 2.658(,u)C(ser')
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(ord and login)-.1 F(shell, are also tainted, for the same reason.)128
282 Q .443(In scalar conte)128 300 R .443
(xt, you get the name, unless the function w)-.15 F .444
(as a lookup by name, in which case you get)-.1 F
(the other thing, whate)128 312 Q -.15(ve)-.25 G 2.5(ri).15 G 2.5(ti)
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(xist you get the unde\214ned v)-2.65 E 2.5(alue.\) F)-.25 F(or e)-.15 E
(xample:)-.15 E F1 12($uid =)152 330 R(getpwnam\($name\);)6 E 6($name =)
152 342 R(getpwuid\($num\);)6 E 6($name =)152 354 R(getpwent\(\);)6 E 12
($gid =)152 366 R(getgrnam\($name\);)6 E 6($name =)152 378 R
(getgrgid\($num\);)6 E 6($name =)152 390 R(getgrent\(\);)6 E(#etc.)152
402 Q F0(In)128 420 Q/F2 10/Times-Italic@0 SF -.1(ge)3.387 G(tpw*\(\)).1
E F0 .887(the \214elds)3.387 F F1($quota)3.387 E F0(,)A F1($comment)
3.387 E F0 3.387(,a)C(nd)-3.387 E F1($expire)3.386 E F0 .886
(are special in that the)3.386 F 3.386(ya)-.15 G .886(re unsupported)
-3.386 F .836(on man)128 432 R 3.336(ys)-.15 G 3.336(ystems. If)-3.336 F
(the)3.336 E F1($quota)3.336 E F0 .836
(is unsupported, it is an empty scalar)3.336 F 5.836(.I)-.55 G 3.336(fi)
-5.836 G 3.336(ti)-3.336 G 3.336(ss)-3.336 G .837(upported, it usually)
-3.336 F .147(encodes the disk quota.)128 444 R .147(If the)5.147 F F1
($comment)2.647 E F0 .147(\214eld is unsupported, it is an empty scalar)
2.647 F 5.146(.I)-.55 G 2.646(fi)-5.146 G 2.646(ti)-2.646 G 2.646(ss)
-2.646 G(upported)-2.646 E .895(it usually encodes some administrati)128
456 R 1.195 -.15(ve c)-.25 H .895(omment about the user).15 F 5.895(.I)
-.55 G 3.395(ns)-5.895 G .895(ome systems the)-3.395 F F1($quota)3.395 E
F0(\214eld)3.395 E 2.471(may be)128 468 R F1($change)4.971 E F0(or)4.971
E F1($age)4.971 E F0 4.971<2c8c>C 2.471(elds that ha)-4.971 F 2.771 -.15
(ve t)-.2 H 4.971(od).15 G 4.971(ow)-4.971 G 2.47(ith passw)-4.971 F
2.47(ord aging.)-.1 F 2.47(In some systems the)7.47 F F1($comment)128
480 Q F0 .68(\214eld may be)3.18 F F1($class)3.18 E F0 5.681(.T)C(he)
-5.681 E F1($expire)3.181 E F0 .681(\214eld, if present, encodes the e)
3.181 F .681(xpiration period of)-.15 F .204(the account or the passw)
128 492 R 2.704(ord. F)-.1 F .204(or the a)-.15 F -.25(va)-.2 G .204
(ilability and the e).25 F .203
(xact meaning of these \214elds in your system,)-.15 F 1.436
(please consult)128 504 R F2 -.1(ge)3.937 G(tpwnam).1 E F0 1.437
(\(3\) and your system')1.666 F(s)-.55 E F2(pwd.h)3.937 E F0 3.937
(\214le. Y)3.937 F 1.437(ou can also \214nd out from within Perl)-1.1 F
.741(what your)128 516 R F1($quota)3.241 E F0(and)3.241 E F1($comment)
3.241 E F0 .741(\214elds mean and whether you ha)3.241 F 1.04 -.15(ve t)
-.2 H(he).15 E F1($expire)3.24 E F0 .74(\214eld by using)3.24 F(the)128
528 Q F1(Config)3.538 E F0 1.038(module and the v)3.538 F(alues)-.25 E
F1(d_pwquota)3.538 E F0(,)A F1(d_pwage)3.538 E F0(,)A F1(d_pwchange)
3.538 E F0(,)A F1(d_pwcomment)3.538 E F0 3.538(,a)C(nd)-3.538 E F1
(d_pwexpire)128 540 Q F0 6.029(.S)C(hado)-6.029 E 3.529(wp)-.25 G(assw)
-3.529 E 1.029(ord \214les are supported only if your v)-.1 F 1.028
(endor has implemented them in)-.15 F 1.888(the intuiti)128 552 R 2.188
-.15(ve f)-.25 H 1.888(ashion that calling the re).05 F 1.888
(gular C library routines gets the shado)-.15 F 4.388(wv)-.25 G 1.888
(ersions if you')-4.538 F(re)-.5 E .336(running under pri)128 564 R
(vile)-.25 E .336(ge or if there e)-.15 F .335(xists the)-.15 F F2
(shadow)2.835 E F0 .335
(\(3\) functions as found in System V \(this includes)1.666 F .093
(Solaris and Linux\).)128 576 R .093
(Those systems that implement a proprietary shado)5.093 F 2.593(wp)-.25
G(assw)-2.593 E .093(ord f)-.1 F .093(acility are unlik)-.1 F(ely)-.1 E
(to be supported.)128 588 Q(The)128 606 Q F1($members)2.534 E F0 -.25
(va)2.534 G .034(lue returned by).25 F F2 -.1(ge)2.534 G(tgr*\(\)).1 E
F0 .034(is a space-separated list of the login names of the members)
2.534 F(of the group.)128 618 Q -.15(Fo)128 636 S 2.868(rt).15 G(he)
-2.868 E F2 -.1(ge)2.868 G(thost*\(\)).1 E F0 .369(functions, if the)
2.869 F F1(h_errno)2.869 E F0 -.25(va)2.869 G .369
(riable is supported in C, it will be returned to you via).25 F F1($?)
128 648 Q F0 .168(if the function call f)2.668 F 2.668(ails. The)-.1 F
F1(@addrs)2.668 E F0 -.25(va)2.668 G .168
(lue returned by a successful call is a list of ra).25 F 2.667(wa)-.15 G
(ddresses)-2.667 E .043(returned by the corresponding library call.)128
660 R .043(In the Internet domain, each address is four bytes long; you)
5.043 F(can unpack it by saying something lik)128 672 Q(e:)-.1 E F1
(\($a,$b,$c,$d\) = unpack\(\010W4\010,$addr[0]\);)152 690 Q F0(The Sock)
128 708 Q(et library mak)-.1 E(es this slightly easier:)-.1 E
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
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(use Socket;)152 84 Q
($iaddr = inet_aton\("127.1"\); # or whatever address)152 96 Q 6
($name =)152 108 R(gethostbyaddr\($iaddr, AF_INET\);)6 E 6(#o)152 132 S
6(rg)-6 G(oing the other way)-6 E($straddr = inet_ntoa\($iaddr\);)152
144 Q F0(In the opposite w)128 162 Q(ay)-.1 E 2.5(,t)-.65 G 2.5(or)-2.5
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SF(IP)2.5 E F0(address you can write this:)2.5 E F1(use Socket;)152 180
Q($packed_ip = gethostbyname\("www.perl.org"\);)152 192 Q
(if \(defined $packed_ip\) {)152 204 Q
($ip_address = inet_ntoa\($packed_ip\);)176 216 Q(})152 228 Q F0(Mak)128
246 Q 3.77(es)-.1 G 1.27(ure <)-3.77 F/F3 10/Times-Italic@0 SF -.1(ge)C
(thostbyname\(\)).1 E F0 3.77(>i)C 3.77(sc)-3.77 G 1.27(alled in)-3.77 F
F2(SCALAR)3.77 E F0(conte)3.77 E 1.27(xt and that its return v)-.15 F
1.269(alue is check)-.25 F 1.269(ed for)-.1 F(de\214nedness.)128 258 Q
.302(If you get tired of remembering which element of the return list c\
ontains which return v)128 276 R .302(alue, by-name)-.25 F(interf)128
288 Q 2.724(aces are pro)-.1 F 2.724(vided in standard modules:)-.15 F
F1(File::stat)5.224 E F0(,)A F1(Net::hostent)5.223 E F0(,)A F1
(Net::netent)5.223 E F0(,)A F1(Net::protoent)128 300 Q F0(,)A F1
(Net::servent)18.89 E F0(,)A F1(Time::gmtime)18.89 E F0(,)A F1
(Time::localtime)18.89 E F0 18.89(,a)C(nd)-18.89 E F1(User::grent)128
312 Q F0 5.673(.T)C .673(hese o)-5.673 F -.15(ve)-.15 G .673
(rride the normal b).15 F .673(uilt-ins, supplying v)-.2 F .672
(ersions that return objects with the)-.15 F
(appropriate names for each \214eld.)128 324 Q -.15(Fo)5 G 2.5(re).15 G
(xample:)-2.65 E F1(use File::stat;)146 342 Q(use User::pwent;)146 354 Q
($is_his = \(stat\($filename\)\255>uid == pwent\($whoever\)\255>uid\);)
146 366 Q F0(Ev)128 384 Q 3.564(en though it looks as though the)-.15 F
(y')-.15 E 3.565(re the same method calls \(uid\), the)-.5 F 6.065(ya)
-.15 G(ren')-6.065 E 3.565(t, because a)-.18 F F1(File::stat)128 396 Q
F0(object is dif)2.5 E(ferent from a)-.25 E F1(User::pwent)2.5 E F0
(object.)2.5 E(getsockname)108 412.8 Q F2(SOCKET)2.5 E F0 .77
(Returns the pack)128 424.8 R .77
(ed sockaddr address of this end of the)-.1 F F2(SOCKET)3.27 E F0 .77
(connection, in case you don')3.27 F 3.269(tk)-.18 G(no)-3.269 E(w)-.25
E(the address because you ha)128 436.8 Q .3 -.15(ve s)-.2 H -2.15 -.25
(ev e).15 H(ral dif).25 E(ferent IPs that the connection might ha)-.25 E
.3 -.15(ve c)-.2 H(ome in on.).15 E F1(use Socket;)152 454.8 Q
($mysockaddr = getsockname\(SOCK\);)152 466.8 Q
(\($port, $myaddr\) = sockaddr_in\($mysockaddr\);)152 478.8 Q
(printf "Connect to %s [%s]\\n",)152 490.8 Q
(scalar gethostbyaddr\($myaddr, AF_INET\),)170 502.8 Q
(inet_ntoa\($myaddr\);)170 514.8 Q F0(getsock)108 531.6 Q(opt)-.1 E F2
(SOCKET)2.5 E F0(,LEVEL,OPTN)A(AME)-.35 E .004(Queries the option named)
128 543.6 R F2(OPTN)2.505 E(AME)-.315 E F0 .005(associated with)2.505 F
F2(SOCKET)2.505 E F0 .005(at a gi)2.505 F -.15(ve)-.25 G(n).15 E F2
(LEVEL)2.505 E F0 5.005(.O)C .005(ptions may e)-5.005 F .005(xist at)
-.15 F 2.95(multiple protocol le)128 555.6 R -.15(ve)-.25 G 2.95
(ls depending on the sock).15 F 2.949(et type, b)-.1 F 2.949
(ut at least the uppermost sock)-.2 F 2.949(et le)-.1 F -.15(ve)-.25 G
(l).15 E F2(SOL_SOCKET)128 567.6 Q F0 2.185(\(de\214ned in the)4.685 F
F1(Socket)4.685 E F0 2.185(module\) will e)4.685 F 2.186(xist. T)-.15 F
4.686(oq)-.8 G 2.186(uery options at another le)-4.686 F -.15(ve)-.25 G
4.686(lt).15 G(he)-4.686 E .127(protocol number of the appropriate prot\
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-.15 F .127(xample, to)-.15 F .807
(indicate that an option is to be interpreted by the)128 591.6 R F2(TCP)
3.307 E F0(protocol,)3.307 E F2(LEVEL)3.307 E F0 .808
(should be set to the protocol)3.307 F(number of)128 603.6 Q F2(TCP)2.5
E F0 2.5(,w)C(hich you can get using)-2.5 E F1(getprotobyname)2.5 E F0
(.)A .086(The function returns a pack)128 621.6 R .086
(ed string representing the requested sock)-.1 F .086(et option, or)-.1
F F1(undef)2.586 E F0 .086(on error)2.586 F 2.586(,w)-.4 G(ith)-2.586 E
2.145(the reason for the error placed in)128 633.6 R F1($!)4.645 E F0
4.645(.J)C 2.145(ust what is in the pack)-4.645 F 2.146
(ed string depends on)-.1 F F2(LEVEL)4.646 E F0(and)4.646 E F2(OPTN)128
645.6 Q(AME)-.315 E F0 2.61(;c)C(onsult)-2.61 E F3 -.1(ge)2.61 G(tsoc).1
E -.1(ko)-.2 G(pt).1 E F0 .11(\(2\) for details.)1.666 F 2.61(Ac)5.11 G
.109(ommon case is that the option is an inte)-2.61 F(ger)-.15 E 2.609
(,i)-.4 G 2.609(nw)-2.609 G(hich)-2.609 E(case the result is a pack)128
657.6 Q(ed inte)-.1 E(ger)-.15 E 2.5(,w)-.4 G(hich you can decode using)
-2.5 E F1(unpack)2.5 E F0(with the)2.5 E F1(i)2.5 E F0(\(or)2.5 E F1(I)
2.5 E F0 2.5(\)f)C(ormat.)-2.5 E(Here')128 675.6 Q 2.5(sa)-.55 G 2.5(ne)
-2.5 G(xample to test whether Nagle')-2.65 E 2.5(sa)-.55 G
(lgorithm is enabled on a sock)-2.5 E(et:)-.1 E F1
(use Socket qw\(:all\);)152 693.6 Q
(defined\(my $tcp = getprotobyname\("tcp"\)\))152 717.6 Q
(or die "Could not determine the protocol number for tcp";)176 729.6 Q
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
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6(#m)152 84 S 6(y$)-6 G(tcp = IPPROTO_TCP; # Alternative)-6 E
(my $packed = getsockopt\($socket, $tcp, TCP_NODELAY\))152 96 Q
(or die "getsockopt TCP_NODELAY: $!";)176 108 Q
(my $nodelay = unpack\("I", $packed\);)152 120 Q(print "Nagle\010s algo\
rithm is turned ", $nodelay ? "off\\n" : "on\\n";)152 132 Q F0(gi)108
148.8 Q -.15(ve)-.25 G(n).15 E/F2 9/Times-Roman@0 SF .25(EXPR BLOCK)2.5
F F0(gi)108 160.8 Q -.15(ve)-.25 G(n).15 E F2(BLOCK)2.5 E F1(given)128
172.8 Q F0 .01(is analogous to the)2.51 F F1(switch)2.51 E F0 -.1(ke)
2.51 G(yw)-.05 E .01(ord in other languages.)-.1 F F1(given)2.51 E F0
(and)2.51 E F1(when)2.51 E F0 .01(are used in Perl to)2.51 F(implement)
128 184.8 Q F1(switch)2.5 E F0(/)A F1(case)A F0(lik)2.5 E 2.5(es)-.1 G
2.5(tatements. Only)-2.5 F -.2(av)2.5 G(ailable after Perl 5.10.)-.05 E
-.15(Fo)5 G 2.5(re).15 G(xample:)-2.65 E F1(use v5.10;)152 202.8 Q
(given \($fruit\) {)152 214.8 Q(when \(/apples?/\) {)176 226.8 Q
(print "I like apples.")200 238.8 Q(})176 250.8 Q(when \(/oranges?/\) {)
176 262.8 Q(print "I don\010t like oranges.")200 274.8 Q(})176 286.8 Q
(default {)176 298.8 Q(print "I don\010t like anything")200 310.8 Q(})
176 322.8 Q(})152 334.8 Q F0(See `)128 352.8 Q(`Switch statements')-.74
E 2.5('i)-.74 G 2.5(np)-2.5 G(erlsyn for detailed information.)-2.5 E
(glob)108 369.6 Q F2(EXPR)2.5 E F0(glob)108 381.6 Q .24(In list conte)
128 393.6 R .239(xt, returns a \(possibly empty\) list of \214lename e)
-.15 F .239(xpansions on the v)-.15 F .239(alue of)-.25 F F2(EXPR)2.739
E F0 .239(such as the)2.739 F 3.36(standard Unix shell)128 405.6 R/F3 10
/Times-Italic@0 SF(/bin/csh)5.86 E F0 -.1(wo)5.86 G 3.36
(uld do. In scalar conte).1 F 3.36
(xt, glob iterates through such \214lename)-.15 F -.15(ex)128 417.6 S
.524(pansions, returning undef when the list is e).15 F .523
(xhausted. This is the internal function implementing the)-.15 F F1
(<*.c>)128 429.6 Q F0(operator)3.16 E 3.16(,b)-.4 G .661
(ut you can use it directly)-3.36 F 3.161(.I)-.65 G(f)-3.161 E F2(EXPR)
3.161 E F0 .661(is omitted,)3.161 F F1($_)3.161 E F0 .661(is used.)3.161
F(The)5.661 E F1(<*.c>)3.161 E F0 .661(operator is)3.161 F
(discussed in more detail in `)128 441.6 Q(`I/O Operators')-.74 E 2.5
('i)-.74 G 2.5(np)-2.5 G(erlop.)-2.5 E 1.134(Note that)128 459.6 R F1
(glob)3.634 E F0 1.134(splits its ar)3.634 F 1.134
(guments on whitespace and treats each se)-.18 F 1.134
(gment as separate pattern.)-.15 F(As)6.134 E(such,)128 471.6 Q F1 1.063
(glob\("*.c *.h"\))3.563 F F0 1.063(matches all \214les with a)3.563 F
F3(.c)3.564 E F0(or)3.564 E F3(.h)3.564 E F0 -.15(ex)3.564 G 3.564
(tension. The).15 F -.15(ex)3.564 G(pression).15 E F1(glob\(".*)3.564 E
(*"\))128 483.6 Q F0(matches all \214les in the current w)2.5 E
(orking directory)-.1 E(.)-.65 E .276
(If non-empty braces are the only wildcard characters used in the)128
501.6 R F1(glob)2.775 E F0 2.775(,n)C 2.775<6f8c>-2.775 G .275
(lenames are matched, b)-2.775 F(ut)-.2 E .297(potentially man)128 513.6
R 2.797(ys)-.15 G .297(trings are returned.)-2.797 F -.15(Fo)5.297 G
2.797(re).15 G .298
(xample, this produces nine strings, one for each pairing of)-2.947 F
(fruits and colors:)128 525.6 Q F1(@many =)152 543.6 Q
(glob "{apple,tomato,cherry}={green,yellow,red}";)12 E F0(Be)128 561.6 Q
.263
(ginning with v5.6.0, this operator is implemented using the standard)
-.15 F F1(File::Glob)2.762 E F0 -.15(ex)2.762 G 2.762(tension. See).15 F
(File::Glob for details, including)128 573.6 Q F1(bsd_glob)2.5 E F0
(which does not treat whitespace as a pattern separator)2.5 E(.)-.55 E
(gmtime)108 590.4 Q F2(EXPR)2.5 E F0(gmtime)108 602.4 Q -.8(Wo)128 614.4
S(rks just lik).8 E 2.5(el)-.1 G(ocaltime b)-2.5 E(ut the returned v)-.2
E(alues are localized for the standard Greenwich time zone.)-.25 E .593
(Note: When called in list conte)128 632.4 R(xt,)-.15 E F1($isdst)3.093
E F0 3.093(,t)C .593(he last v)-3.093 F .594
(alue returned by gmtime, is al)-.25 F -.1(wa)-.1 G(ys).1 E F1(0)3.094 E
F0 5.594(.T)C .594(here is)-5.594 F(no Daylight Sa)128 644.4 Q(ving T)
-.2 E(ime in)-.35 E F2(GMT)2.5 E F0(.)A(See `)128 662.4 Q(`gmtime')-.74
E 2.5('i)-.74 G 2.5(np)-2.5 G(erlport for portability concerns.)-2.5 E
(goto)108 679.2 Q F2(LABEL)2.5 E F0(goto)108 691.2 Q F2(EXPR)2.5 E F0
(goto &N)108 703.2 Q(AME)-.35 E(The)128 715.2 Q F1(goto\255LABEL)2.654 E
F0 .154(form \214nds the statement labeled with)2.654 F F2(LABEL)2.654 E
F0 .154(and resumes e)2.654 F -.15(xe)-.15 G .153(cution there. It can')
.15 F(t)-.18 E .396(be used to get out of a block or subroutine gi)128
727.2 R -.15(ve)-.25 G 2.897(nt).15 G(o)-2.897 E F1(sort)2.897 E F0
5.397(.I)C 2.897(tc)-5.397 G .397(an be used to go almost an)-2.897 F
.397(ywhere else)-.15 F(perl v5.14.2)72 768 Q 198.17(2011-10-01 31)
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
(uted Perl Documentation)-.2 E(PERLFUNC\(1\))95.355 E 2.018
(within the dynamic scope, including out of subroutines, b)128 84 R
2.018(ut it')-.2 F 4.518(su)-.55 G 2.018
(sually better to use some other)-4.518 F .545(construct such as)128 96
R/F1 10/Courier@0 SF(last)3.045 E F0(or)3.045 E F1(die)3.045 E F0 5.545
(.T)C .545(he author of Perl has ne)-5.545 F -.15(ve)-.25 G 3.046(rf).15
G .546(elt the need to use this form of)-3.046 F F1(goto)3.046 E F0 .559
(\(in Perl, that is; C is another matter\).)128 108 R .559(\(The dif)
5.559 F .559(ference is that C does not of)-.25 F .558
(fer named loops combined)-.25 F(with loop control.)128 120 Q
(Perl does, and this replaces most structured uses of)5 E F1(goto)2.5 E
F0(in other languages.\))2.5 E(The)128 138 Q F1(goto\255EXPR)2.903 E F0
.403(form e)2.903 F .404
(xpects a label name, whose scope will be resolv)-.15 F .404
(ed dynamically)-.15 F 5.404(.T)-.65 G .404(his allo)-5.404 F(ws)-.25 E
2.359(for computed)128 150 R F1(goto)4.859 E F0 4.859(sp)C(er)-4.859 E
/F2 9/Times-Roman@0 SF(FOR)4.859 E(TRAN)-.54 E F0 4.859(,b)C 2.359
(ut isn')-5.059 F 4.859(tn)-.18 G 2.359(ecessarily recommended if you')
-4.859 F 2.359(re optimizing for)-.5 F(maintainability:)128 162 Q F1
(goto \("FOO", "BAR", "GLARCH"\)[$i];)152 180 Q F0 1.015(As sho)128 198
R 1.016(wn in this e)-.25 F(xample,)-.15 E F1(goto\255EXPR)3.516 E F0
1.016(is e)3.516 F -.15(xe)-.15 G 1.016(mpt from the `).15 F 1.016
(`looks lik)-.74 F 3.516(eaf)-.1 G(unction')-3.516 E 3.516('r)-.74 G
1.016(ule. A pair of)-3.516 F 3.94(parentheses follo)128 210 R 3.94
(wing it does not \(necessarily\) delimit its ar)-.25 F(gument.)-.18 E
F1(goto\("NE"\)."XT")6.44 E F0(is)6.44 E(equi)128 222 Q -.25(va)-.25 G
(lent to).25 E F1(goto NEXT)2.5 E F0(.)A .075(Use of)128 240 R F1
(goto\255LABEL)2.575 E F0(or)2.575 E F1(goto\255EXPR)2.575 E F0 .075
(to jump into a construct is deprecated and will issue a w)2.575 F
(arning.)-.1 E(Ev)128 252 Q .315
(en then, it may not be used to go into an)-.15 F 2.815(yc)-.15 G .315
(onstruct that requires initialization, such as a subroutine)-2.815 F
(or a)128 264 Q F1(foreach)2.5 E F0 2.5(loop. It)2.5 F(also can')2.5 E
2.5(tb)-.18 G 2.5(eu)-2.5 G
(sed to go into a construct that is optimized a)-2.5 E -.1(wa)-.15 G
-.65(y.).1 G(The)128 282 Q F1(goto\255&NAME)2.746 E F0 .247
(form is quite dif)2.746 F .247(ferent from the other forms of)-.25 F F1
(goto)2.747 E F0 5.247(.I)C 2.747(nf)-5.247 G .247(act, it isn')-2.847 F
2.747(tag)-.18 G .247(oto in the)-2.747 F 1.698
(normal sense at all, and doesn')128 294 R 4.198(th)-.18 G -2.25 -.2
(av e)-4.198 H 1.698(the stigma associated with other gotos.)4.398 F
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184.8 Q F0(If)128 202.8 Q F2(SIGN)3.45 E(AL)-.315 E F0 .95
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(xample:)-.15 E F1(use POSIX qw\(strftime\);)152 516 Q
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(ymous hashes each with only one entry apiece.)-.15 E(mkdir)108 334.8 Q
F2(FILEN)2.5 E(AME)-.315 E F0(,MASK)A(mkdir)108 346.8 Q F2(FILEN)2.5 E
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F0 2.572(\). If)B .072
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(In general, it is better to create directories with a permissi)128
412.8 R -.15(ve)-.25 G F2(MASK)3.302 E F0 .652
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3.15 E F0 .65(than it is to supply a restricti)3.15 F -.15(ve)-.25 G F2
(MASK)3.299 E F0 .649(and gi)3.149 F .949 -.15(ve t)-.25 H .649
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(ly create a directory structure, look at the).15 E F1(mkpath)2.5 E F0
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(ID)2.5 E F0(,CMD,ARG)A(Calls the System V)128 537.6 Q F2(IPC)2.5 E F0
(function)2.5 E F3(msgctl)2.5 E F0 2.5(\(2\). Y)1.666 F(ou')-1.1 E
(ll probably ha)-.1 E .3 -.15(ve t)-.2 H 2.5(os).15 G(ay)-2.5 E F1
(use IPC::SysV;)152 555.6 Q F0 .739
(\214rst to get the correct constant de\214nitions.)128 573.6 R(If)5.739
E F2(CMD)3.239 E F0(is)3.239 E F1(IPC_STAT)3.239 E F0 3.239(,t)C(hen)
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3.434(structure. Returns)3.434 F(lik)3.434 E(e)-.1 E F1(ioctl)3.434 E F0
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(See also `)5.75 F(`SysV)-.74 E F2(IPC)3.25 E F0 2.23 -.74('' i)D 3.25
(np).74 G .75(erlipc and the)-3.25 F(documentation for)128 609.6 Q F1
(IPC::SysV)2.5 E F0(and)2.5 E F1(IPC::Semaphore)2.5 E F0(.)A(msgget)108
626.4 Q F2(KEY)2.5 E F0(,FLA)A(GS)-.4 E .671(Calls the System V)128
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679.2 R F2(IPC)3.562 E F0 1.062(function msgrcv to recei)3.562 F 1.362
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-1.215(VA)3.259 G(R)1.215 E F0 3.259(,f)C(ollo)-3.259 E .759
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(may be opened with)128 715.2 R F1 .903(unpack\("l! a*"\))3.403 F F0
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(documentation.)2.5 E(my)108 177.6 Q F2(EXPR)2.5 E F0(my)108 189.6 Q F2
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(declares the listed v)2.766 F .267(ariables to be local \(le)-.25 F
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(The e)128 255.6 R .572(xact semantics and interf)-.15 F .572(ace of)-.1
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(utes are handled using the)-.2 F F1(attributes)4.812 E F0 2.313
(pragma, or)4.813 F .774(starting from Perl 5.8.0 also via the)128 279.6
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-.2 E(ute::Handlers.)-.2 E(ne)108 308.4 Q(xt)-.15 E F2(LABEL)2.5 E F0
(ne)108 320.4 Q(xt)-.15 E(The)128 332.4 Q F1(next)2.5 E F0
(command is lik)2.5 E 2.5(et)-.1 G(he)-2.5 E F1(continue)2.5 E F0
(statement in C; it starts the ne)2.5 E(xt iteration of the loop:)-.15 E
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6(#d)12 G(iscard comments)-6 E(#...)176 374.4 Q(})152 386.4 Q F0 1.285
(Note that if there were a)128 404.4 R F1(continue)3.785 E F0 1.285
(block on the abo)3.785 F -.15(ve)-.15 G 3.785(,i).15 G 3.785(tw)-3.785
G 1.286(ould get e)-3.885 F -.15(xe)-.15 G 1.286(cuted e).15 F -.15(ve)
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(is omitted, the command refers to the innermost enclosing loop.)2.5 E
F1(next)128 434.4 Q F0 .662(cannot be used to e)3.162 F .662
(xit a block which returns a v)-.15 F .661(alue such as)-.25 F F1 .661
(eval {})3.161 F F0(,)A F1 .661(sub {})3.161 F F0 3.161(,o)C(r)-3.161 E
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(xit a)-.15 E F3(gr)2.5 E(ep\(\))-.37 E F0(or)2.5 E F3(map\(\))2.5 E F0
(operation.)2.5 E .379
(Note that a block by itself is semantically identical to a loop that e)
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2.879 E F0 .379(will e)2.879 F(xit)-.15 E(such a block early)128 476.4 Q
(.)-.65 E(See also `)128 494.4 Q(`continue')-.74 E 2.5('f)-.74 G
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2.5 E F0 2.5(,a)C(nd)-2.5 E F1(redo)2.5 E F0 -.1(wo)2.5 G(rk.).1 E(no)
108 511.2 Q F2 .25(MODULE VERSION LIST)2.5 F F0(no)108 523.2 Q F2 .25
(MODULE VERSION)2.5 F F0(no)108 535.2 Q F2 .25(MODULE LIST)2.5 F F0(no)
108 547.2 Q F2(MODULE)2.5 E F0(no)108 559.2 Q F2(VERSION)2.5 E F0
(See the)128 571.2 Q F1(use)2.5 E F0(function, of which)2.5 E F1(no)2.5
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(Interprets)128 600 Q F2(EXPR)3.154 E F0 .654
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(f)-.25 E(with)128 612 Q F1(0x)3.396 E F0 3.396(,i)C .896
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F2(EXPR)3.397 E F0 .897(starts of)3.397 F 3.397(fw)-.25 G(ith)-3.397 E
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(nterpreted as a binary string.)-3.397 F 1.105
(Leading whitespace is ignored in all three cases.\))128 624 R 1.105
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152 654 Q F0(If)128 672 Q F2(EXPR)4.345 E F0 1.846(is omitted, uses)
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1.846(he other w)-4.346 F 1.846(ay \(produce a number in octal\), use)
-.1 F F3(sprintf\(\))4.346 E F0(or)4.346 E F3(printf\(\))128 684 Q F0(:)
A F1($dec_perms = \(stat\("filename"\)\)[2] & 07777;)152 702 Q
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(oct)A F0(only handles non-ne)2.5 E -.05(ga)-.15 G(ti).05 E .3 -.15
(ve i)-.25 H(nte).15 E(gers, not ne)-.15 E -.05(ga)-.15 G(ti).05 E .3
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154.8 Q/F3 9/Times-Roman@0 SF(FILEHANDLE)2.5 E F0(,EXPR)A(open)108 166.8
Q F3(FILEHANDLE)2.5 E F0(,MODE,EXPR)A(open)108 178.8 Q F3(FILEHANDLE)2.5
E F0(,MODE,EXPR,LIST)A(open)108 190.8 Q F3(FILEHANDLE)2.5 E F0
(,MODE,REFERENCE)A(open)108 202.8 Q F3(FILEHANDLE)2.5 E F0
(Opens the \214le whose \214lename is gi)128 214.8 Q -.15(ve)-.25 G 2.5
(nb).15 G(y)-2.5 E F3(EXPR)2.5 E F0 2.5(,a)C(nd associates it with)-2.5
E F3(FILEHANDLE)2.5 E F0(.)A(Simple e)128 232.8 Q
(xamples to open a \214le for reading:)-.15 E F2
(open\(my $fh, "<", "input.txt"\))152 250.8 Q
(or die "cannot open < input.txt: $!";)176 262.8 Q F0(and for writing:)
128 280.8 Q F2(open\(my $fh, ">", "output.txt"\))152 298.8 Q
(or die "cannot open > output.txt: $!";)176 310.8 Q F0 1.108
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(perlopentut.\))128 340.8 Q(If)128 358.8 Q F3(FILEHANDLE)5.015 E F0
2.514(is an unde\214ned scalar v)5.014 F 2.514
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2.514(lehandle is)-5.014 F(auto)128 370.8 Q(vi)-.15 E 2.676
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(wly allocated anon)-.25 F(ymous)-.15 E 4.727(\214lehandle. Otherwise)
128 382.8 R(if)4.727 E F3(FILEHANDLE)4.727 E F0 2.227(is an e)4.727 F
2.227(xpression, its v)-.15 F 2.226(alue is the real \214lehandle.)-.25
F 2.226(\(This is)7.226 F(considered a symbolic reference, so)128 394.8
Q F2(use strict "refs")2.5 E F0(should)2.5 E F1(not)2.5 E F0(be in ef)
2.5 E(fect.\))-.25 E(If)128 412.8 Q F3(EXPR)4.759 E F0 2.259
(is omitted, the global \(package\) scalar v)4.759 F 2.259
(ariable of the same name as the)-.25 F F3(FILEHANDLE)4.76 E F0 1.737
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(xical v)-.15 F -.834(ariables \212 those)-.25 F 1.736(declared with)
4.236 F F2(my)4.236 E F0(or)4.236 E F2(state)4.236 E F0 1.736
(\255\255will not)B -.1(wo)128 436.8 S(rk for this purpose; so if you')
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(If three \(or more\) ar)128 454.8 R .336(guments are speci\214ed, the \
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466.8 Q .834(gument are distinct from the \214lename in the third.)-.18
F(If)5.833 E F3(MODE)3.333 E F0(is)3.333 E F2(<)3.333 E F0 .833
(or nothing, the \214le is opened for)3.333 F 6.055(input. If)128 478.8
R F3(MODE)6.055 E F0(is)6.055 E F2(>)6.055 E F0 6.055(,t)C 3.555
(he \214le is opened for output, with e)-6.055 F 3.556
(xisting \214les \214rst being truncated)-.15 F(\(`)128 490.8 Q
(`clobbered')-.74 E .679('\) and none)-.74 F .679(xisting \214les ne)
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-3.179 F(ag)128 502.8 Q(ain being created if necessary)-.05 E(.)-.65 E
-1.1(Yo)128 520.8 S 2.95(uc)1.1 G .45(an put a)-2.95 F F2(+)2.95 E F0
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(+<)3.021 E F0 .521(is almost al)3.021 F -.1(wa)-.1 G .521
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-.1 F -1.1(Yo)128 544.8 S 4.138(uc)1.1 G 1.638
(ant usually use either read-write mode for updating te)-4.138 F 1.639
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(The \214le is created with permissions of)6.11 F F2(0666)128 568.8 Q F0
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G(lue.).25 E(These v)128 586.8 Q(arious pre\214x)-.25 E
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(he \214lename is interpreted as a command to which output)-2.639 F .102
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<ad7c>2.602 E F0 2.602(,t)C .102
(he \214lename is interpreted as a command that pipes output to us.)
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('' i)D 3.972(np).74 G 1.472(erlipc for more e)-3.972 F 1.472
(xamples of this.)-.15 F(\(Y)6.472 E 1.472(ou are not allo)-1.1 F 1.472
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150 Q F0(.)A -1.1(Yo)128 168 S 3.223(um)1.1 G .723
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(\(see open and PerlIO for more details\). F)128 192 Q(or e)-.15 E
(xample:)-.15 E F2(open\(my $fh, "<:encoding\(UTF\2558\)", "filename"\))
140 210 Q(|| die "can\010t open UTF\2558 encoded filename: $!";)152 222
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(Open returns nonzero on success, the unde\214ned v)128 282 R 1.327
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E -.2(vo)-.4 G(lv).2 E 1.328(ed a pipe, the)-.15 F(return v)128 294 Q
(alue happens to be the pid of the subprocess.)-.25 E 1.679(If you')128
312 R 1.678(re running Perl on a system that distinguishes between te)
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(binmode)2.735 E F0 .235(and those that don')2.735 F 2.735(ti)-.18 G
2.735(st)-2.735 G .235(heir te)-2.735 F .235(xt \214le formats.)-.15 F
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2.735 E F0 2.735(,a)C .234(nd Plan 9,)-2.735 F .477(that end lines with\
 a single character and encode that character in C as)128 348 R F2
("\\n")2.977 E F0 .477(do not need)2.977 F F2(binmode)2.977 E F0(.)A
(The rest need it.)128 360 Q .762(When opening a \214le, it')128 378 R
3.261(ss)-.55 G .761(eldom a good idea to continue if the request f)
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3.261 F .021(used with)128 390 R F2(die)2.521 E F0 5.021(.E)C -.15(ve)
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(wa)-.1 G 1.74(ys check the).1 F(return v)128 414 Q
(alue from opening a \214le.)-.25 E 2.07(As a special case the three-ar)
128 432 R 2.071(gument form with a read/write mode and the third ar)-.18
F 2.071(gument being)-.18 F F2(undef)128 444 Q F0(:)A F2
(open\(my $tmp, "+>", undef\) or die ...)152 462 Q F0 .123
(opens a \214lehandle to an anon)128 480 R .123(ymous temporary \214le.)
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(rks for symmetry).1 F 2.623(,b)-.65 G .123(ut you really)-2.823 F 2.14
(should consider writing something to the temporary \214le \214rst.)128
492 R -1.1(Yo)7.14 G 4.64(uw)1.1 G 2.14(ill need to)-4.64 F/F4 10
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504 Q .147(Since v5.8.0, Perl has b)128 522 R .147
(uilt using PerlIO by def)-.2 F 2.647(ault. Unless)-.1 F(you')2.647 E
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(uilding Perl)-.2 F(with)128 534 Q F2(Configure \255Uuseperlio)2.5 E F0
(\), you can open \214lehandles directly to Perl scalars via:)A F2
(open\($fh, ">", \\$variable\) || ..)152 552 Q F0 1.6 -.8(To \()128 570
T(re\)open).8 E F2(STDOUT)2.5 E F0(or)2.5 E F2(STDERR)2.5 E F0
(as an in-memory \214le, close it \214rst:)2.5 E F2(close STDOUT;)152
588 Q(open\(STDOUT, ">", \\$variable\))152 600 Q
(or die "Can\010t open STDOUT: $!";)176 612 Q F0(General e)128 630 Q
(xamples:)-.15 E F2($ARTICLE = 100;)152 648 Q
(open\(ARTICLE\) or die "Can\010t find article $ARTICLE: $!\\n";)152 660
Q(while \(<ARTICLE>\) {...)152 672 Q
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264 S(n\255memory files)-6 E(open\(MEMORY, ">", \\$var\))152 276 Q
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(print MEMORY "foo!\\n";)152 300 Q 6(#o)114 G(utput will appear in $var)
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(foreach $file \(@ARGV\) {)152 348 Q(process\($file, "fh00"\);)176 360 Q
(})152 372 Q(sub process {)152 396 Q(my\($filename, $input\) = @_;)176
408 Q 18($input++; #)176 420 R(this is a string increment)6 E
(unless \(open\($input, "<", $filename\)\) {)176 432 Q
(print STDERR "Can\010t open $filename: $!\\n";)200 444 Q(return;)200
456 Q(})176 468 Q(local $_;)176 492 Q(while \(<$input>\) {)176 504 Q 6
(#n)24 G(ote use of indirection)-6 E(if \(/^#include "\(.*\)"/\) {)200
516 Q(process\($1, $input\);)224 528 Q(next;)224 540 Q(})200 552 Q 54
(#... #)200 564 R(whatever)6 E(})176 576 Q(})152 588 Q F0
(See perliol for detailed info on PerlIO.)128 606 Q -1.1(Yo)128 624 S
2.543(um)1.1 G .043(ay also, in the Bourne shell tradition, specify an)
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(hich case the rest)-2.544 F .774(of the string is interpreted as the n\
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3.273(fn)-3.273 G .773(umeric\) to be duped \(as)-3.273 F F1(dup\(2\))
128 648 Q F0 4.098(\)a)C 1.598(nd opened.)-4.098 F -1.1(Yo)6.598 G 4.098
(um)1.1 G 1.598(ay use)-4.098 F F1(&)4.098 E F0(after)4.098 E F1(>)4.098
E F0(,)A F1(>>)4.098 E F0(,)A F1(<)4.098 E F0(,)A F1(+>)4.098 E F0(,)A
F1(+>>)4.098 E F0 4.099(,a)C(nd)-4.099 E F1(+<)4.099 E F0 6.599(.T)C
1.599(he mode you specify)-6.599 F .283
(should match the mode of the original \214lehandle.)128 660 R .282
(\(Duping a \214lehandle does not tak)5.283 F 2.782(ei)-.1 G .282
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(open\(STDOUT, ">&", $oldout\) or die "Can\010t dup \\$oldout: $!";)152
240 Q(open\(STDERR, ">&OLDERR"\))152 252 Q
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(open\(FILEHANDLE, "<&=$fd"\))152 360 Q F0(or)128 378 Q F1
(open\(FILEHANDLE, "<&=", $fd\))152 396 Q F0(or)128 414 Q F1 6(#o)152
432 S(pen for append, using the fileno of OLDFH)-6 E
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Q(open\(FOO, "cat \255n \010$file\010|"\);)152 390 Q
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(open\(FOO, "\255|"\) || exec "cat", "\255n", $file;)152 414 Q
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(sysopen\(HANDLE, $path, O_RDWR|O_CREAT|O_EXCL\))152 414 Q
(or die "sysopen $path: $!";)176 426 Q
($oldfh = select\(HANDLE\); $| = 1; select\($oldfh\);)152 438 Q
(print HANDLE "stuff $$\\n";)152 450 Q(seek\(HANDLE, 0, 0\);)152 462 Q
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(Using the constructor from the)128 492 R F1(IO::Handle)3.127 E F0 .627
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152 558 Q(sub read_myfile_munged {)152 570 Q(my $ALL = shift;)176 582 Q
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(my $handle = IO::File\255>new;)176 606 Q
(open\($handle, "<", "myfile"\) or die "myfile: $!";)176 618 Q
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(ord)108 243.6 Q F2(EXPR)2.5 E F0(ord)108 255.6 Q .666
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128 386.4 R .428(xical scope of the)-.15 F F1(our)2.928 E F0 2.928
(declaration. In)2.928 F(this)2.928 E -.1(wa)128 398.4 S(y).1 E F1(our)
2.5 E F0(dif)2.5 E(fers from)-.25 E F1(use vars)2.5 E F0 2.5(,w)C
(hich is package-scoped.)-2.5 E(Unlik)128 416.4 Q(e)-.1 E F1(my)3.482 E
F0(or)3.482 E F1(state)3.482 E F0 3.482(,w)C .981
(hich allocates storage for a v)-3.482 F .981
(ariable and associates a simple name with that)-.25 F .585
(storage for use within the current scope,)128 428.4 R F1(our)3.086 E F0
.586(associates a simple name with a package \(read: global\))3.086 F
-.25(va)128 440.4 S .548
(riable in the current package, for use within the current le).25 F .548
(xical scope.)-.15 F .548(In other w)5.548 F(ords,)-.1 E F1(our)3.048 E
F0 .548(has the)3.048 F(same scoping rules as)128 452.4 Q F1(my)2.5 E F0
(or)2.5 E F1(state)2.5 E F0 2.5(,b)C(ut does not necessarily create a v)
-2.7 E(ariable.)-.25 E(If more than one v)128 470.4 Q
(alue is listed, the list must be placed in parentheses.)-.25 E F1
(our $foo;)152 488.4 Q(our\($bar, $baz\);)152 500.4 Q F0(An)128 518.4 Q
F1(our)3.065 E F0 .565(declaration declares a global v)3.065 F .566
(ariable that will be visible across its entire le)-.25 F .566
(xical scope, e)-.15 F -.15(ve)-.25 G(n).15 E .286
(across package boundaries.)128 530.4 R .286(The package in which the v)
5.286 F .285(ariable is entered is determined at the point of)-.25 F
(the declaration, not at the point of use.)128 542.4 Q
(This means the follo)5 E(wing beha)-.25 E(vior holds:)-.2 E F1
(package Foo;)152 560.4 Q(our $bar;)152 572.4 Q 6(#d)36 G
(eclares $Foo::bar for rest of lexical scope)-6 E($bar = 20;)152 584.4 Q
(package Bar;)152 608.4 Q(print $bar;)152 620.4 Q 6(#p)24 G
(rints 20, as it refers to $Foo::bar)-6 E F0(Multiple)128 638.4 Q F1
(our)3.67 E F0 1.17(declarations with the same name in the same le)3.67
F 1.171(xical scope are allo)-.15 F 1.171(wed if the)-.25 F 3.671(ya)
-.15 G 1.171(re in)-3.671 F(dif)128 650.4 Q 1.317(ferent packages.)-.25
F 1.317(If the)6.317 F 3.817(yh)-.15 G 1.316
(appen to be in the same package, Perl will emit w)-3.817 F 1.316
(arnings if you ha)-.1 F -.15(ve)-.2 G(ask)128 662.4 Q .908
(ed for them, just lik)-.1 F 3.408(em)-.1 G(ultiple)-3.408 E F1(my)3.408
E F0 3.408(declarations. Unlik)3.408 F 3.408(eas)-.1 G(econd)-3.408 E F1
(my)3.408 E F0 .908(declaration, which will bind)3.408 F 1.306
(the name to a fresh v)128 674.4 R 1.306(ariable, a second)-.25 F F1
(our)3.806 E F0 1.306
(declaration in the same package, in the same scope, is)3.806 F
(merely redundant.)128 686.4 Q(perl v5.14.2)72 768 Q 198.17
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36 G(eclares $Foo::bar for rest of lexical scope)-6 E($bar = 20;)152 120
Q(package Bar;)152 144 Q
(our $bar = 30; # declares $Bar::bar for rest of lexical scope)152 156 Q
(print $bar;)152 168 Q 6(#p)24 G(rints 30)-6 E(our $bar;)152 192 Q 6(#e)
36 G(mits warning but has no other effect)-6 E(print $bar;)152 204 Q 6
(#s)24 G(till prints 30)-6 E F0(An)128 222 Q F1(our)2.5 E F0
(declaration may also ha)2.5 E .3 -.15(ve a l)-.2 H(ist of attrib).15 E
(utes associated with it.)-.2 E .571(The e)128 240 R .571
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(is currently bound to)3.072 F 1.043(the use of)128 252 R F1(fields)
3.542 E F0 1.042(pragma, and attrib)3.542 F 1.042
(utes are handled using the)-.2 F F1(attributes)3.542 E F0 1.042
(pragma, or starting)3.542 F .366(from Perl 5.8.0 also via the)128 264 R
F1(Attribute::Handlers)2.866 E F0 2.866(module. See)2.866 F -.74(``)
2.866 G(Pri).74 E -.25(va)-.25 G .366(te V).25 F .366(ariables via)-1.11
F/F3 10/Times-Italic@0 SF(my\(\))2.867 E F0 1.847 -.74('' i)D(n).74 E
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-.2 E(ute::Handlers.)-.2 E(pack)108 292.8 Q F2(TEMPLA)2.5 E(TE)-.999 E
F0(,LIST)A -.8(Ta)128 304.8 S -.1(ke).8 G 3.996(sa).1 G F2(LIST)A F0
1.496(of v)3.996 F 1.496(alues and con)-.25 F -.15(ve)-.4 G 1.496
(rts it into a string using the rules gi).15 F -.15(ve)-.25 G 3.995(nb)
.15 G 3.995(yt)-3.995 G(he)-3.995 E F2(TEMPLA)3.995 E(TE)-.999 E F0
6.495(.T)C(he)-6.495 E .035
(resulting string is the concatenation of the con)128 316.8 R -.15(ve)
-.4 G .036(rted v).15 F 2.536(alues. T)-.25 F(ypically)-.8 E 2.536(,e)
-.65 G .036(ach con)-2.536 F -.15(ve)-.4 G .036(rted v).15 F .036
(alue looks lik)-.25 F(e)-.1 E .105(its machine-le)128 328.8 R -.15(ve)
-.25 G 2.605(lr).15 G 2.605(epresentation. F)-2.605 F .105(or e)-.15 F
.104(xample, on 32\255bit machines an inte)-.15 F .104
(ger may be represented by a)-.15 F(sequence of 4 bytes, which)128 340.8
Q(will in Perl be presented as a string that')5 E 2.5(s4c)-.55 G
(haracters long.)-2.5 E
(See perlpacktut for an introduction to this function.)128 358.8 Q(The)
128 376.8 Q F2(TEMPLA)2.5 E(TE)-.999 E F0
(is a sequence of characters that gi)2.5 E .3 -.15(ve t)-.25 H
(he order and type of v).15 E(alues, as follo)-.25 E(ws:)-.25 E F1 12
(aA)152 394.8 S(string with arbitrary binary data, will be null padded.)
-6 E 12(AA)152 406.8 S(text \(ASCII\) string, will be space padded.)-6 E
12(ZA)152 418.8 S
(null\255terminated \(ASCIZ\) string, will be null padded.)-6 E 12(bA)
152 442.8 S
(bit string \(ascending bit order inside each byte, like vec\(\)\).)-6 E
12(BA)152 454.8 S(bit string \(descending bit order inside each byte\).)
-6 E 12(hA)152 466.8 S(hex string \(low nybble first\).)-6 E 12(HA)152
478.8 S(hex string \(high nybble first\).)-6 E 12(cA)152 502.8 S
(signed char \(8\255bit\) value.)-6 E 12(CA)152 514.8 S 6(nu)-12 G
(nsigned char \(octet\) value.)-6 E 12(WA)152 526.8 S 6(nu)-12 G
(nsigned char value \(can be greater than 255\).)-6 E 12(sA)152 550.8 S
(signed short \(16\255bit\) value.)-6 E 12(SA)152 562.8 S 6(nu)-12 G
(nsigned short value.)-6 E 12(lA)152 586.8 S
(signed long \(32\255bit\) value.)-6 E 12(LA)152 598.8 S 6(nu)-12 G
(nsigned long value.)-6 E 12(qA)152 622.8 S
(signed quad \(64\255bit\) value.)-6 E 12(QA)152 634.8 S 6(nu)-12 G
(nsigned quad value.)-6 E
(\(Quads are available only if your system supports 64\255bit)164 646.8
Q(integer values _and_ if Perl has been compiled to support those.)170
658.8 Q(Raises an exception otherwise.\))194 670.8 Q 12(iA)152 694.8 S
(signed integer value.)-6 E 12(IA)152 706.8 S(unsigned integer value.)-6
E(\(This \010integer\010 is _at_least_ 32 bits wide.)164 718.8 Q
(Its exact)12 E
(size depends on what a local C compiler calls \010int\010.\))194 730.8
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12(vA)152 120 S 6(nu)-12 G
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(jA)152 156 S(Perl internal signed integer value \(IV\).)-12 E 18(JA)152
168 S(Perl internal unsigned integer value \(UV\).)-12 E 12(fA)152 192 S
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(DA)152 240 S(float of long\255double precision in native format.)-6 E
(\(Long doubles are available only if your system supports long)164 252
Q(double values _and_ if Perl has been compiled to support those.)170
264 Q(Raises an exception otherwise.\))194 276 Q 12(pA)152 300 S
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(pointer to a structure \(fixed\255length string\).)-6 E 12(uA)152 336 S
(uuencoded string.)-6 E 12(UA)152 348 S(Unicode character number.)-6 E
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360 Q 12(wA)152 384 S
(BER compressed integer \(not an ASN.1 BER, see perlpacktut for)-6 E 6
(details\). Its)170 396 R
(bytes represent an unsigned integer in base 128,)6 E
(most significant digit first, with as few digits as possible.)170 408 Q
(Bit)12 E(eight \(the high bit\) is set on each byte except the last.)
170 420 Q 12(xA)152 444 S
(null byte \(a.k.a ASCII NUL, "\\000", chr\(0\)\))-6 E 12(XB)152 456 S
(ack up a byte.)-12 E 12(@N)152 468 S
(ull\255fill or truncate to absolute position, counted from the)-12 E
(start of the innermost \(\)\255group.)170 480 Q 12(.N)152 492 S
(ull\255fill or truncate to absolute position specified by the value.)
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(One or more modi\214ers belo)128 522 R 4.277(wm)-.25 G 1.777
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(of fixed \(16\255/32\255bit\) sizes.)242 564 Q 48(xX Make)176 588 R 6
(xa)6 G(nd X act as alignment commands.)-6 E 36(nNvV Treat)176 612 R
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R("big end" touches the construct.\))6 E 18(<s)152 720 S 12
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(The)128 102 Q F1(>)5.14 E F0(and)5.14 E F1(<)5.14 E F0 2.64
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(components in that group, including all its subgroups.)128 114 Q
(The follo)128 132 Q(wing rules apply:)-.25 E<83>128 148.8 Q 1.792
(Each letter may optionally be follo)148 148.8 R 1.792
(wed by a number indicating the repeat count.)-.25 F 4.293(An)6.793 G
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2.994 E F0 .494(when used with all format types other than)2.994 F F1(a)
148 184.8 Q F0(,)A F1(A)2.838 E F0(,)A F1(Z)2.838 E F0(,)A F1(b)2.838 E
F0(,)A F1(B)2.838 E F0(,)A F1(h)2.838 E F0(,)A F1(H)2.838 E F0(,)A F1(@)
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2.838(,a)C(nd)-2.838 E F1(P)2.838 E F0 2.838(,w)C .338
(here it means something else, dscribed belo)-2.838 F 4.138 -.65(w. S)
-.25 H(upplying).65 E(a)148 196.8 Q F1(*)3.4 E F0 .9
(for the repeat count instead of a number means to use ho)3.4 F(we)-.25
E -.15(ve)-.25 G 3.401(rm).15 G(an)-3.401 E 3.401(yi)-.15 G .901
(tems are left, e)-3.401 F(xcept)-.15 E(for:)148 208.8 Q<83>148 225.6 Q
F1(@)168 225.6 Q F0(,)A F1(x)2.5 E F0 2.5(,a)C(nd)-2.5 E F1(X)2.5 E F0
2.5(,w)C(here it is equi)-2.5 E -.25(va)-.25 G(lent to).25 E F1(0)2.5 E
F0(.)A<83>148 242.4 Q(<.>, where it means relati)168 242.4 Q .3 -.15
(ve t)-.25 H 2.5(ot).15 G(he start of the string.)-2.5 E<83>148 259.2 Q
F1(u)168 259.2 Q F0 2.5(,w)C(here it is equi)-2.5 E -.25(va)-.25 G
(lent to 1 \(or 45, which here is equi).25 E -.25(va)-.25 G(lent\).).25
E 1.388(One can replace a numeric repeat count with a template letter e\
nclosed in brack)148 277.2 R 1.387(ets to use the)-.1 F(pack)148 289.2 Q
(ed byte length of the brack)-.1 E(eted template for the repeat count.)
-.1 E -.15(Fo)148 307.2 S 3.008(re).15 G .508(xample, the template)
-3.158 F F1(x[L])3.009 E F0 .509(skips as man)3.009 F 3.009(yb)-.15 G
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("$t)3.009 E .598(X[$t] $t")148 319.2 R F0 .598(unpacks twice whate)
3.098 F -.15(ve)-.25 G(r).15 E F1($t)3.098 E F0 .597(\(when v)3.098 F
(ariable-e)-.25 E .597(xpanded\) unpacks.)-.15 F .597
(If the template in)5.597 F(brack)148 331.2 Q .34
(ets contains alignment commands \(such as)-.1 F F1(x![d])2.84 E F0 .34
(\), its pack)B .34(ed length is calculated as if the)-.1 F
(start of the template had the maximal possible alignment.)148 343.2 Q
1.889(When used with)148 361.2 R F1(Z)4.389 E F0 4.389(,a)C F1(*)A F0
1.889
(as the repeat count is guaranteed to add a trailing null byte, so the)
4.389 F(resulting string is al)148 373.2 Q -.1(wa)-.1 G
(ys one byte longer than the byte length of the item itself.).1 E
(When used with)148 391.2 Q F1(@)2.5 E F0 2.5(,t)C
(he repeat count represents an of)-2.5 E
(fset from the start of the innermost)-.25 E F1(\(\))2.5 E F0(group.)2.5
E .622(When used with)148 409.2 R F1(.)3.122 E F0 3.122(,t)C .623
(he repeat count determines the starting position to calculate the v)
-3.122 F .623(alue of)-.25 F(fset)-.25 E(as follo)148 421.2 Q(ws:)-.25 E
<83>148 438 Q(If the repeat count is)168 438 Q F1(0)2.5 E F0 2.5(,i)C
(t')-2.5 E 2.5(sr)-.55 G(elati)-2.5 E .3 -.15(ve t)-.25 H 2.5(ot).15 G
(he current position.)-2.5 E<83>148 454.8 Q(If the repeat count is)168
454.8 Q F1(*)2.5 E F0 2.5(,t)C(he of)-2.5 E(fset is relati)-.25 E .3
-.15(ve t)-.25 H 2.5(ot).15 G(he start of the pack)-2.5 E(ed string.)-.1
E<83>148 471.6 Q .019(And if it')168 471.6 R 2.519(sa)-.55 G 2.519(ni)
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2.519(,t)C .019(he of)-2.519 F .019(fset is relati)-.25 F .319 -.15
(ve t)-.25 H 2.519(ot).15 G .018(he start of the)-2.519 F F3(n)2.518 E
F0 .018(th innermost)B F1 6.018(\(\))2.518 G F0 .018(group, or to)-3.5 F
(the start of the string if)168 483.6 Q F3(n)2.5 E F0
(is bigger then the group le)2.5 E -.15(ve)-.25 G(l.).15 E .075
(The repeat count for)148 501.6 R F1(u)2.575 E F0 .075(is interpreted a\
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h 0, 1 and 2 replaced by 45. The repeat count should not be more than 6\
5.)148 513.6 Q<83>128 530.4 Q(The)148 530.4 Q F1(a)2.863 E F0(,)A F1(A)
2.863 E F0 2.863(,a)C(nd)-2.863 E F1(Z)2.863 E F0 .363
(types gobble just one v)2.863 F .363(alue, b)-.25 F .363
(ut pack it as a string of length count, padding with)-.2 F 2.027
(nulls or spaces as needed.)148 542.4 R 2.027(When unpacking,)7.027 F F1
(A)4.527 E F0 2.027(strips trailing whitespace and nulls,)4.527 F F1(Z)
4.528 E F0(strips)4.528 E -2.15 -.25(ev e)148 554.4 T
(rything after the \214rst null, and).25 E F1(a)2.5 E F0
(returns data with no stripping at all.)2.5 E .997(If the v)148 572.4 R
.997(alue to pack is too long, the result is truncated.)-.25 F .996
(If it')5.996 F 3.496(st)-.55 G .996(oo long and an e)-3.496 F .996
(xplicit count is)-.15 F(pro)148 584.4 Q(vided,)-.15 E F1(Z)4.509 E F0
2.009(packs only)4.509 F F1($count\2551)4.509 E F0 2.009(bytes, follo)
4.509 F 2.009(wed by a null byte.)-.25 F(Thus)7.01 E F1(Z)4.51 E F0(al)
4.51 E -.1(wa)-.1 G 2.01(ys packs a).1 F(trailing null, e)148 596.4 Q
(xcept when the count is 0.)-.15 E<83>128 613.2 Q(Lik)148 613.2 Q -.25
(ew)-.1 G 2.309(ise, the).25 F F1(b)4.809 E F0(and)4.808 E F1(B)4.808 E
F0 2.308(formats pack a string that')4.808 F 4.808(st)-.55 G 2.308
(hat man)-4.808 F 4.808(yb)-.15 G 2.308(its long.)-4.808 F 2.308
(Each such format)7.308 F(generates 1 bit of the result.)148 625.2 Q
(These are typically follo)5 E(wed by a repeat count lik)-.25 E(e)-.1 E
F1(B8)2.5 E F0(or)2.5 E F1(B64)2.5 E F0(.)A .96(Each result bit is base\
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148 643.2 R 3.46(,i)-.4 G .96(.e., on)-3.46 F F1(ord\($char\)%2)148
655.2 Q F0 5.44(.I)C 2.94(np)-5.44 G(articular)-2.94 E 2.94(,c)-.4 G
(haracters)-2.94 E F1("0")2.94 E F0(and)2.94 E F1("1")2.94 E F0 .44
(generate bits 0 and 1, as do characters)2.94 F F1("\\000")148 667.2 Q
F0(and)2.5 E F1("\\001")2.5 E F0(.)A 1.918(Starting from the be)148
685.2 R 1.919
(ginning of the input string, each 8\255tuple of characters is con)-.15
F -.15(ve)-.4 G 1.919(rted to 1).15 F 2.382(character of output.)148
697.2 R -.4(Wi)7.382 G 2.382(th format).4 F F1(b)4.882 E F0 4.882(,t)C
2.381(he \214rst character of the 8\255tuple determines the least-)
-4.882 F(signi\214cant bit of a character; with format)148 709.2 Q F1(B)
2.5 E F0 2.5(,i)C 2.5(td)-2.5 G
(etermines the most-signi\214cant bit of a character)-2.5 E(.)-.55 E
.097(If the length of the input string is not e)148 727.2 R -.15(ve)-.25
G .097(nly di).15 F .098(visible by 8, the remainder is pack)-.25 F .098
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(string were padded by null characters at the end.)148 84 R 1.078
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132 Q/F1 10/Courier@0 SF(*)2.606 E F0 .106
(for the repeat count uses all characters of the input \214eld.)2.606 F
.106(On unpacking, bits are con)5.106 F -.15(ve)-.4 G .107(rted to).15 F
2.5(as)148 144 S(tring of)-2.5 E F1(0)2.5 E F0 2.5(sa)C(nd)-2.5 E F1(1)
2.5 E F0(s.)A<83>128 160.8 Q(The)148 160.8 Q F1(h)2.604 E F0(and)2.604 E
F1(H)2.604 E F0 .103(formats pack a string that man)2.604 F 2.603(yn)
-.15 G .103(ybbles \(4\255bit groups, representable as he)-2.753 F
(xadecimal)-.15 E(digits,)148 172.8 Q F1 -3.5("0".."9" "a".."f")2.5 F F0
2.5(\)l)C(ong.)-2.5 E -.15(Fo)148 190.8 S 4.065(re).15 G 1.565
(ach such format,)-4.065 F/F2 10/Times-Italic@0 SF(pac)4.065 E(k\(\))-.2
E F0 1.565(generates 4 bits of result.)4.065 F -.4(Wi)6.566 G 1.566
(th non-alphabetical characters, the).4 F .129(result is based on the 4\
 least-signi\214cant bits of the input character)148 202.8 R 2.629(,i)
-.4 G .129(.e., on)-2.629 F F1(ord\($char\)%16)2.629 E F0 5.129(.I)C(n)
-5.129 E(particular)148 214.8 Q 2.697(,c)-.4 G(haracters)-2.697 E F1
("0")2.697 E F0(and)2.697 E F1("1")2.697 E F0 .197(generate n)2.697 F
.197(ybbles 0 and 1, as do bytes)-.15 F F1("\\000")2.698 E F0(and)2.698
E F1("\\001")2.698 E F0(.)A -.15(Fo)148 226.8 S 3.145(rc).15 G
(haracters)-3.145 E F1("a".."f")3.145 E F0(and)3.145 E F1("A".."F")3.145
E F0 3.145(,t)C .645(he result is compatible with the usual he)-3.145 F
(xadecimal)-.15 E 1.252(digits, so that)148 238.8 R F1("a")3.752 E F0
(and)3.752 E F1("A")3.752 E F0 1.252(both generate the n)3.752 F(ybble)
-.15 E F1(0xA==10)3.752 E F0 6.252(.U)C 1.252
(se only these speci\214c he)-6.252 F(x)-.15 E
(characters with this format.)148 250.8 Q 1.072(Starting from the be)148
268.8 R 1.072(ginning of the template to)-.15 F F2(pac)3.572 E(k\(\))-.2
E F0 3.572(,e)C 1.072(ach pair of characters is con)-3.572 F -.15(ve)-.4
G 1.071(rted to 1).15 F .482(character of output.)148 280.8 R -.4(Wi)
5.483 G .483(th format).4 F F1(h)2.983 E F0 2.983(,t)C .483
(he \214rst character of the pair determines the least-signi\214cant)
-2.983 F -.15(ny)148 292.8 S(bble of the output character; with format)
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(etermines the most-signi\214cant n)-2.5 E(ybble.)-.15 E .359
(If the length of the input string is not e)148 310.8 R -.15(ve)-.25 G
.359(n, it beha).15 F -.15(ve)-.2 G 2.859(sa).15 G 2.859(si)-2.859 G
2.859(fp)-2.859 G .359(added by a null character at the end.)-2.859 F
(Similarly)148 322.8 Q 2.5(,`)-.65 G(`e)-3.24 E(xtra')-.15 E 2.5('n)-.74
G(ybbles are ignored during unpacking.)-2.65 E
(If the input string is longer than needed, e)148 340.8 Q
(xtra characters are ignored.)-.15 E(A)148 358.8 Q F1(*)2.528 E F0 .028
(for the repeat count uses all characters of the input \214eld.)2.528 F
-.15(Fo)5.028 G(r).15 E F2(unpac)2.529 E(k\(\))-.2 E F0 2.529(,n)C .029
(ybbles are con)-2.679 F -.15(ve)-.4 G(rted).15 E(to a string of he)148
370.8 Q(xadecimal digits.)-.15 E<83>128 387.6 Q(The)148 387.6 Q F1(p)
3.441 E F0 .941(format packs a pointer to a null-terminated string.)
3.441 F -1.1(Yo)5.941 G 3.44(ua)1.1 G .94
(re responsible for ensuring that)-3.44 F .057
(the string is not a temporary v)148 399.6 R .058
(alue, as that could potentially get deallocated before you got around)
-.25 F .077(to using the pack)148 411.6 R .077(ed result.)-.1 F(The)
5.077 E F1(P)2.577 E F0 .076
(format packs a pointer to a structure of the size indicated by the)
2.576 F 3.154(length. A)148 423.6 R .654
(null pointer is created if the corresponding v)3.154 F .654(alue for)
-.25 F F1(p)3.154 E F0(or)3.154 E F1(P)3.154 E F0(is)3.154 E F1(undef)
3.154 E F0 3.155(;s)C .655(imilarly with)-3.155 F F2(unpac)148 435.6 Q
(k\(\))-.2 E F0 2.5(,w)C(here a null pointer unpacks into)-2.5 E F1
(undef)2.5 E F0(.)A .123(If your system has a strange pointer size)148
453.6 R 1.666<8a6d>1.666 G .123
(eaning a pointer is neither as big as an int nor as big)-1.666 F .506
(as a long)148 465.6 R 1.666<8a69>1.666 G 3.007(tm)-1.666 G .507(ay not\
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(xception.)-.15 E<83>128 494.4 Q(The)148 494.4 Q F1(/)2.764 E F0 .264
(template character allo)2.764 F .264
(ws packing and unpacking of a sequence of items where the pack)-.25 F
(ed)-.1 E .745(structure contains a pack)148 506.4 R .745
(ed item count follo)-.1 F .745(wed by the pack)-.25 F .745
(ed items themselv)-.1 F 3.245(es. This)-.15 F .745(is useful)3.245 F
.405(when the structure you')148 518.4 R .404(re unpacking has encoded \
the sizes or repeat counts for some of its \214elds)-.5 F
(within the structure itself as separate \214elds.)148 530.4 Q -.15(Fo)
148 548.4 S(r).15 E F1(pack)3.759 E F0 3.759(,y)C 1.259(ou write)-3.759
F F2(length-item)3.759 E F1(/)A F2(sequence-item)A F0 3.759(,a)C 1.259
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3.759(wt)-.25 G 1.26(he length)-3.759 F -.25(va)148 560.4 S .298
(lue is pack).25 F .298(ed. F)-.1 F .298(ormats lik)-.15 F .298
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-.2 F(e)-.1 E F1(n)2.797 E F0 .297(for Ja)2.797 F .797 -.25(va s)-.2 H
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-.15(ve a r)-.2 H .918
(epeat count, in which case the minimum of that and the).15 F .012
(number of a)148 602.4 R -.25(va)-.2 G .011
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(length-item)2.511 E F0 2.511(.I)C 2.511(fi)-2.511 G 2.511(th)-2.511 G
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(ou write)-1.1 F F1(/)148 644.4 Q F2(sequence-item)A F0 .681
(and the repeat count is obtained by popping of)3.181 F 3.181(ft)-.25 G
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(not the number of strings.)148 686.4 R -.4(Wi)5.257 G .257(th an e).4 F
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(ed string is adjusted to)-.1 F(that length.)148 698.4 Q -.15(Fo)5 G 2.5
(re).15 G(xample:)-2.65 E(perl v5.14.2)72 768 Q 198.17(2011-10-01 51)
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(ay:)-.1 E F1(printf "format s is %d, s! is %d\\n",)172 274.8 Q
(length pack\("s"\), length pack\("s!"\);)196 286.8 Q
(printf "format l is %d, l! is %d\\n",)172 310.8 Q
(length pack\("l"\), length pack\("l!"\);)196 322.8 Q(i!)148 340.8 Q F0
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(The actual sizes \(in bytes\) of nati)148 358.8 R .542 -.15(ve s)-.25 H
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(erl \255V:{short,int,long{,long}}size)-6 E(shortsize=\0102\010;)172
400.8 Q(intsize=\0104\010;)172 412.8 Q(longsize=\0104\010;)172 424.8 Q
(longlongsize=\0108\010;)172 436.8 Q F0(or programmatically via the)148
454.8 Q F1(Config)2.5 E F0(module:)2.5 E F1(use Config;)190 472.8 Q
(print $Config{shortsize},)190 484.8 Q("\\n";)24 E
(print $Config{intsize},)190 496.8 Q("\\n";)36 E
(print $Config{longsize},)190 508.8 Q("\\n";)30 E
(print $Config{longlongsize}, "\\n";)190 520.8 Q($Config{longlongsize})
148 538.8 Q F0(is unde\214ned on systems without long long support.)2.5
E<83>128 555.6 Q .118(The inte)148 555.6 R .118(ger formats)-.15 F F1(s)
2.618 E F0(,)A F1(S)2.618 E F0(,)A F1(i)2.618 E F0(,)A F1(I)2.618 E F0
(,)A F1(l)2.618 E F0(,)A F1(L)2.618 E F0(,)A F1(j)2.618 E F0 2.618(,a)C
(nd)-2.618 E F1(J)2.618 E F0 .119
(are inherently non-portable between processors and)2.618 F 1.384
(operating systems because the)148 567.6 R 3.884(yo)-.15 G(be)-3.884 E
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(xample, a 4\255byte)-4.033 F(inte)148 579.6 Q .18
(ger 0x12345678 \(305419896 decimal\) w)-.15 F .181
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(0x78 0x56 0x34 0x12)172 621.6 Q 6(#l)12 G(ittle\255endian)-6 E F0
(Basically)148 639.6 Q 5.311(,I)-.65 G 2.811(ntel and)-5.311 F F3 -1.215
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-.15(ve)-.25 G 2.811(rybody else, including Motorola).15 F(m68k/88k,)148
651.6 Q F3(PPC)3.241 E F0 3.241(,S)C(parc,)-3.241 E F3 .991(HP P)3.241 F
(A)-.828 E F0 3.241(,P)C -.25(ow)-3.241 G(er).25 E 3.241(,a)-.4 G .741
(nd Cray)-3.241 F 3.241(,a)-.65 G .741(re big-endian.)-3.241 F .741
(Alpha and)5.741 F F3(MIPS)3.241 E F0 .742(can be either:)3.241 F 1.559
(Digital/Compaq uses \(well, used\) them in little-endian mode, b)148
663.6 R 1.559(ut SGI/Cray uses them in big-)-.2 F(endian mode.)148 675.6
Q .238(The names)148 693.6 R F2(big-endian)2.738 E F0(and)2.738 E F2
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148 705.6 R F2(Gulliver')148 717.6 Q 3.944(sT)-.4 G -.15(ra)-4.494 G
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(his entered computer lingo via the paper `)-6.444 F 1.444(`On Holy W)
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(0x56 0x78 0x12 0x34)166 102 Q(0x34 0x12 0x78 0x56)166 114 Q F0 -1.1(Yo)
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Q F0(The byteorder on the platform where Perl w)148 168 Q(as b)-.1 E
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(use Config;)172 186 Q(print "$Config{byteorder}\\n";)172 198 Q F0
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F1(n)4.317 E F0(,)A F1(N)4.317 E F0(,)A F1(v)4.317 E F0 4.317(,a)C(nd)
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(and)4.317 E F1(<)4.317 E F0(modi\214ers described immediately belo)148
294 Q 3.8 -.65(w. S)-.25 H(ee also perlport.).65 E<83>128 310.8 Q .882
(Starting with Perl 5.9.2, inte)148 310.8 R .882
(ger and \215oating-point formats, along with the)-.15 F F1(p)3.382 E F0
(and)3.382 E F1(P)3.382 E F0 .882(formats and)3.382 F F1(\(\))148 322.8
Q F0 .625(groups, may all be follo)3.125 F .625(wed by the)-.25 F F1(>)
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(ly enforce big\255).15 F .519(or little-endian byte-order)148 334.8 R
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3.018 E F0(,)A F1(v)3.018 E F0 3.018(,a)C(nd)-3.018 E F1(V)3.018 E F0
(don')3.018 E(t)-.18 E(co)148 346.8 Q -.15(ve)-.15 G 2.5(rs).15 G
(igned inte)-2.5 E(gers, 64\255bit inte)-.15 E
(gers, or \215oating-point v)-.15 E(alues.)-.25 E
(Here are some concerns to k)148 364.8 Q
(eep in mind when using an endianness modi\214er:)-.1 E<83>148 381.6 Q
.157(Exchanging signed inte)168 381.6 R .157(gers between dif)-.15 F
.157(ferent platforms w)-.25 F .158(orks only when all platforms store)
-.1 F 3.111(them in the same format.)168 393.6 R 3.111
(Most platforms store signed inte)8.111 F 3.111(gers in tw)-.15 F(o')-.1
E(s-complement)-.55 E(notation, so usually this is not an issue.)168
405.6 Q<83>148 422.4 Q(The)168 422.4 Q F1(>)3.922 E F0(or)3.922 E F1(<)
3.922 E F0 1.422(modi\214ers can only be used on \215oating-point forma\
ts on big\255 or little-endian)3.922 F 2.5(machines. Otherwise,)168
434.4 R(attempting to use them raises an e)2.5 E(xception.)-.15 E<83>148
451.2 Q -.15(Fo)168 451.2 S .359
(rcing big\255 or little-endian byte-order on \215oating-point v).15 F
.358(alues for data e)-.25 F .358(xchange can w)-.15 F(ork)-.1 E .312
(only if all platforms use the same binary representation such as)168
463.2 R/F2 9/Times-Roman@0 SF(IEEE)2.812 E F0 2.812
(\215oating-point. Ev)2.812 F .312(en if)-.15 F .505
(all platforms are using)168 475.2 R F2(IEEE)3.005 E F0 3.005(,t)C .505
(here may still be subtle dif)-3.005 F 3.005(ferences. Being)-.25 F .505
(able to use)3.005 F F1(>)3.005 E F0(or)3.005 E F1(<)3.005 E F0 1.072
(on \215oating-point v)168 487.2 R 1.073(alues can be useful, b)-.25 F
1.073(ut also dangerous if you don')-.2 F 3.573(tk)-.18 G(no)-3.573 E
3.573(we)-.25 G 1.073(xactly what)-3.723 F(you')168 499.2 Q(re doing.)
-.5 E(It is not a general w)5 E(ay to portably store \215oating-point v)
-.1 E(alues.)-.25 E<83>148 516 Q .909(When using)168 516 R F1(>)3.409 E
F0(or)3.409 E F1(<)3.409 E F0 .909(on a)3.409 F F1(\(\))3.409 E F0 .909
(group, this af)3.409 F .909
(fects all types inside the group that accept byte-)-.25 F .878
(order modi\214ers, including all subgroups.)168 528 R .879
(It is silently ignored for all other types.)5.878 F -1.1(Yo)5.879 G
3.379(ua)1.1 G(re)-3.379 E .505(not allo)168 540 R .505(wed to o)-.25 F
-.15(ve)-.15 G .505(rride the byte-order within a group that already ha\
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Q .632(Real numbers \(\215oats and doubles\) are in nati)148 568.8 R
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(ue to the multiplicity of)-5.632 F .845
(\215oating-point formats and the lack of a standard `)148 580.8 R
(`netw)-.74 E(ork')-.1 E 3.344('r)-.74 G .844
(epresentation for them, no f)-3.344 F(acility)-.1 E 2.453
(for interchange has been made.)148 592.8 R 2.453(This means that pack)
7.453 F 2.453(ed \215oating-point data written on one)-.1 F .182
(machine may not be readable on another)148 604.8 R 2.682(,e)-.4 G -.15
(ve)-2.932 G 2.682(ni).15 G 2.682(fb)-2.682 G .182(oth use)-2.682 F F2
(IEEE)2.682 E F0 .181(\215oating-point arithmetic \(because)2.682 F
(the endianness of the memory representation is not part of the)148
616.8 Q F2(IEEE)2.5 E F0 2.5(spec\). See)2.5 F(also perlport.)2.5 E .692
(If you kno)148 634.8 R(w)-.25 E/F3 10/Times-Italic@0 SF -.2(ex)3.192 G
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F F1(>)3.192 E F0(or)3.192 E F1(<)3.192 E F0 .692
(modi\214ers to force big\255 or little-)3.192 F
(endian byte-order on \215oating-point v)148 646.8 Q(alues.)-.25 E .565
(Because Perl uses doubles \(or long doubles, if con\214gured\) interna\
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G .468(rting from double into \215oat and thence to double ag).15 F .468
(ain loses precision, so)-.05 F F1(unpack\("f",)2.968 E
(pack\("f", $foo\))148 688.8 Q F0 2.5(\)w)C(ill not in general equal)
-2.5 E F1($foo)2.5 E F0(.)A<83>128 705.6 Q -.15(Pa)148 705.6 S .028
(ck and unpack can operate in tw).15 F 2.528(om)-.1 G .028
(odes: character mode \()-2.528 F F1(C0)A F0 .028(mode\) where the pack)
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3.064(,a)-.4 G(nd)-3.064 E F2(UTF\2558)3.064 E F0 .564(mode \()3.064 F
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172 156 S(erl \255CS \255E \010say "\\x{3B1}\\x{3C9}"\010 |)-6 E(perl \
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(erl \255CS \255E \010say "\\x{3B1}\\x{3C9}"\010 |)-6 E(perl \255CS \
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(erl \255CS \255E \010say "\\x{3B1}\\x{3C9}"\010 |)-6 E(perl \255C0 \
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(CE.B1.CF.89)172 252 Q 6($p)172 264 S
(erl \255CS \255E \010say "\\x{3B1}\\x{3C9}"\010 |)-6 E(perl \255C0 \
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(C3.8E.C2.B1.C3.8F.C2.89)172 288 Q F0 .941(Those e)148 306 R .941
(xamples also illustrate that you should not try to use)-.15 F F1(pack)
3.44 E F0(/)A F1(unpack)A F0 .94(as a substitute for)3.44 F
(the Encode module.)148 318 Q<83>128 334.8 Q -1.1(Yo)148 334.8 S 3.245
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R 1.638(is no w)4.138 F 1.638(ay for)-.1 F F2(pac)4.138 E(k\(\))-.2 E F0
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(coming from, so the)148 358.8 Q 2.5(yh)-.15 G
(andle their output and input as \215at sequences of characters.)-2.5 E
<83>128 375.6 Q(A)148 375.6 Q F1(\(\))4.011 E F0 1.511
(group is a sub-TEMPLA)4.011 F 1.511(TE enclosed in parentheses.)-1.11 F
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(unpac)3.404 E(k\(\))-.2 E F0 3.404(,a)C .904(lso via the)-3.404 F F1(/)
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F1(@)2.5 E F0(starts o)2.5 E -.15(ve)-.15 G 2.5(ra).15 G 2.5(t0)-2.5 G
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(pack\("@1A\(\(@2A\)@3A\)", qw[X Y Z]\))172 417.6 Q F0(is the string)148
435.6 Q F1("\\0X\\0\\0YZ")2.5 E F0(.)A<83>128 452.4 Q F1(x)148 452.4 Q
F0(and)3.202 E F1(X)3.202 E F0 .702(accept the)3.202 F F1(!)3.202 E F0
.702(modi\214er to act as alignment commands: the)3.202 F 3.202(yj)-.15
G .702(ump forw)-3.202 F .703(ard or back to the)-.1 F .537
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F0 .537(characters. F)3.037 F .537(or e)-.15 F .536(xample, to)-.15 F F2
(pac)3.036 E(k\(\))-.2 E F0(or)3.036 E F2(unpac)3.036 E(k\(\))-.2 E F0
(a)3.036 E 2.5(Cs)148 476.4 S(tructure lik)-2.5 E(e)-.1 E F1(struct {)
172 494.4 Q 12(char c;)196 506.4 R(/* one signed, 8\255bit character */)
24 E(double d;)196 518.4 Q 12(char cc[2];)196 530.4 R(})172 542.4 Q F0
1.63(one may need to use the template)148 560.4 R F1 7.63(cx)4.13 G 1.63
(![d] d c[2])-7.63 F F0 6.63(.T)C 1.63(his assumes that doubles must be)
-6.63 F(aligned to the size of double.)148 572.4 Q -.15(Fo)148 590.4 S
2.5(ra).15 G(lignment commands, a)-2.5 E F1(count)2.5 E F0(of 0 is equi)
2.5 E -.25(va)-.25 G(lent to a).25 E F1(count)2.5 E F0
(of 1; both are no-ops.)2.5 E<83>128 607.2 Q F1(n)148 607.2 Q F0(,)A F1
(N)2.975 E F0(,)A F1(v)2.975 E F0(and)2.975 E F1(V)2.975 E F0 .475
(accept the)2.975 F F1(!)2.975 E F0 .474
(modi\214er to represent signed 16\255/32\255bit inte)2.975 F .474
(gers in big\255/little\255endian)-.15 F(order)148 619.2 Q 7.892(.T)-.55
G 2.892(his is portable only when all platforms sharing pack)-7.892 F
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(representation for signed inte)148 631.2 R 3.274(gers; for e)-.15 F
3.274(xample, when all platforms use tw)-.15 F(o')-.1 E(s-complement)
-.55 E(representation.)148 643.2 Q<83>128 660 Q .732
(Comments can be embedded in a)148 660 R/F3 9/Times-Roman@0 SF(TEMPLA)
3.232 E(TE)-.999 E F0(using)3.232 E F1(#)3.233 E F0 .733
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($foo = pack\("WWWW",65,66,67,68\);)152 132 Q 6(#f)152 144 S
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168 S(ame thing)-6 E($foo = pack\("W4",0x24b6,0x24b7,0x24b8,0x24b9\);)
152 180 Q 6(#s)152 192 S(ame thing with Unicode circled letters.)-6 E
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S(ame thing with Unicode circled letters. You don\010t get the UTF\2558)
-6 E 6(#b)152 228 S
(ytes because the U at the start of the format caused a switch to)-6 E 6
(#U)152 240 S
(0\255mode, so the UTF\2558 bytes get joined into characters)-6 E
($foo = pack\("C0U4",0x24b6,0x24b7,0x24b8,0x24b9\);)152 252 Q 6(#f)152
264 S
(oo eq "\\xe2\\x92\\xb6\\xe2\\x92\\xb7\\xe2\\x92\\xb8\\xe2\\x92\\xb9")-6
E 6(#T)152 276 S
(his is the UTF\2558 encoding of the string in the previous example)-6 E
($foo = pack\("ccxxcc",65,66,67,68\);)152 300 Q 6(#f)152 312 S
(oo eq "AB\\0\\0CD")-6 E 6(#N)152 336 S
(OTE: The examples above featuring "W" and "c" are true)-6 E 6(#o)152
348 S(nly on ASCII and ASCII\255derived systems such as ISO Latin 1)-6 E
6(#a)152 360 S(nd UTF\2558.)-6 E
(On EBCDIC systems, the first example would be)12 E 36(#$)152 372 S
(foo = pack\("WWWW",193,194,195,196\);)-36 E($foo = pack\("s2",1,2\);)
152 396 Q 6(#")152 408 S(\\001\\000\\002\\000" on little\255endian)-6 E
6(#")152 420 S(\\000\\001\\000\\002" on big\255endian)-6 E
($foo = pack\("a4","abcd","x","y","z"\);)152 444 Q 6(#")152 456 S(abcd")
-6 E($foo = pack\("aaaa","abcd","x","y","z"\);)152 480 Q 6(#")152 492 S
(axyz")-6 E($foo = pack\("a14","abcdefg"\);)152 516 Q 6(#")152 528 S
(abcdefg\\0\\0\\0\\0\\0\\0\\0")-6 E($foo = pack\("i9pl", gmtime\);)152
552 Q 6(#ar)152 564 S(eal struct tm \(on my system anyway\))-6 E
($utmp_template = "Z8 Z8 Z16 L";)152 588 Q
($utmp = pack\($utmp_template, @utmp1\);)152 600 Q 6(#as)152 612 S
(truct utmp \(BSDish\))-6 E(@utmp2 = unpack\($utmp_template, $utmp\);)
152 636 Q 6(#")152 648 S(@utmp1" eq "@utmp2")-6 E(sub bintodec {)152 672
Q(unpack\("N", pack\("B32", substr\("0" x 32 . shift, \25532\)\)\);)176
684 Q(})152 696 Q($foo = pack\(\010sx2l\010, 12, 34\);)152 720 Q F0
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($foo = pack\(\010S>L>\010, 42, 4711\);)152 192 Q 6(#e)152 204 S
(xactly the same)-6 E($foo = pack\(\010s<l<\010, \25542, 4711\);)152 216
Q 6(#p)152 228 S
(ack little\255endian 16\255 and 32\255bit signed integers)-6 E
($foo = pack\(\010\(sl\)<\010, \25542, 4711\);)152 240 Q 6(#e)152 252 S
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(The same template may generally also be used in)128 270 Q/F2 10
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F3 -.315(NA)2.5 G(MESP).315 E -.36(AC)-.828 G 2.5(EV).36 G .25
(ERSION BLOCK)-2.5 F F0 .141(Declares the)128 334.8 R F3(BLOCK)2.641 E
F0 .141(or the rest of the compilation unit as being in the gi)2.641 F
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(BLOCK)3.157 E F0 .657(are operati)3.157 F .957 -.15(ve t)-.25 H .657
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(our)3.13 E F0 3.13(operators. All)3.13 F .629
(unquali\214ed dynamic identi\214ers in this scope will be in the gi)
3.13 F -.15(ve)-.25 G 3.129(nn).15 G(amespace,)-3.129 E -.15(ex)128
394.8 S 3.02(cept where o).15 F -.15(ve)-.15 G 3.02(rridden by another)
.15 F F1(package)5.52 E F0 3.02(declaration or when the)5.52 F(y')-.15 E
3.02(re one of the special)-.5 F(identi\214ers that qualify into)128
406.8 Q F1(main::)2.5 E F0 2.5(,l)C(ik)-2.5 E(e)-.1 E F1(STDOUT)2.5 E F0
(,)A F1(ARGV)2.5 E F0(,)A F1(ENV)2.5 E F0 2.5(,a)C(nd the punctuation v)
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-.65 G .726(ncluding those you')-3.226 F 1.026 -.15(ve u)-.5 H(sed).15 E
F1(local)3.226 E F0 .726(on, b)3.226 F(ut)-.2 E F2(not)3.226 E F0(le)128
436.8 Q 2.853(xical v)-.15 F 2.853(ariables, which are created with)-.25
F F1(my)5.353 E F0(,)A F1(state)5.353 E F0 5.353(,o)C(r)-5.353 E F1(our)
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(ould be the \214rst)-.1 F .608(declaration in a \214le included by)128
448.8 R F1(require)3.108 E F0(or)3.108 E F1(use)3.108 E F0 5.608(.Y)C
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(place, since this only determines which def)128 460.8 R 1.506
(ault symbol table the compiler uses for the rest of that)-.1 F 3.532
(block. Y)128 472.8 R 1.032(ou can refer to identi\214ers in other pack\
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(with the package name and a double colon, as in)128 484.8 R F1
($SomePack::var)13.484 E F0(or)13.484 E F1(ThatPack::INPUT_HANDLE)128
496.8 Q F0 6.056(.I)C 3.556(fp)-6.056 G 1.056
(ackage name is omitted, the)-3.556 F F1(main)3.555 E F0 1.055
(package as assumed.)3.555 F(That)6.055 E(is,)128 508.8 Q F1($::sail)
2.727 E F0 .227(is equi)2.727 F -.25(va)-.25 G .227(lent to).25 F F1
($main::sail)2.727 E F0 .227(\(as well as to)2.727 F F1($main\010sail)
2.727 E F0 2.728(,s)C .228(till seen in ancient code,)-2.728 F
(mostly from Perl 4\).)128 520.8 Q(If)128 538.8 Q F3(VERSION)3.027 E F0
.527(is pro)3.027 F(vided,)-.15 E F1(package)3.026 E F0 .526(sets the)
3.026 F F1($VERSION)3.026 E F0 -.25(va)3.026 G .526(riable in the gi).25
F -.15(ve)-.25 G 3.026(nn).15 G .526(amespace to a v)-3.026 F(ersion)
-.15 E .666(object with the)128 550.8 R F3(VERSION)3.166 E F0(pro)3.166
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(ersion number as de\214ned by)-.15 F .243(the v)128 562.8 R .243
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(ecimal number \(inte).15 F .242(ger or decimal-fraction\) without e)
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(v' character and at least three components.)-.5 F -1.1(Yo)5.37 G 2.87
(us)1.1 G(hould)-2.87 E(set)128 586.8 Q F1($VERSION)2.5 E F0
(only once per package.)2.5 E .521(See `)128 604.8 R(`P)-.74 E(ackages')
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(erlmod for more information about packages, modules, and classes.)
-3.021 F .52(See perlsub)5.52 F(for other scoping issues.)128 616.8 Q
(pipe)108 633.6 Q F3(READHANDLE)2.5 E F0(,WRITEHANDLE)A .538
(Opens a pair of connected pipes lik)128 645.6 R 3.038(et)-.1 G .538
(he corresponding system call.)-3.038 F .538
(Note that if you set up a loop of)5.538 F .071
(piped processes, deadlock can occur unless you are v)128 657.6 R .071
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-.55 G .07(ipes use)-2.57 F F3(IO)128 669.6 Q F0 -.2(bu)2.567 G -.25(ff)
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(to \215ush your)2.568 F F3(WRITEHANDLE)2.568 E F0 .068
(after each command, depending)2.568 F(on the application.)128 681.6 Q
1.24(See IPC::Open2, IPC::Open3, and `)128 699.6 R 1.24
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152 84 Q(my $substring = \010quick.*?fox\010;)152 96 Q
($sentence =~ s{$substring}{big bad wolf};)152 108 Q F0 -.4(Wi)128 126 S
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(\010The big bad wolf jumped over...\010)2.5 E F0(.)A
(On the other hand:)128 144 Q F1
(my $sentence = \010The quick brown fox jumped over the lazy dog\010;)
152 162 Q(my $substring = \010quick.*?fox\010;)152 174 Q
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204 Q F1
(my $sentence = \010The quick brown fox jumped over the lazy dog\010;)
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(Returns a random fractional number greater than or equal to)128 370.8 R
F1(0)2.518 E F0 .018(and less than the v)2.518 F .018(alue of)-.25 F F3
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502.8 S(rsion of Perl w).15 E
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-.25 F(the last character of the scalar after the read.)128 633.6 Q(An)
128 651.6 Q F3(OFFSET)4.883 E F0 2.383(may be speci\214ed to place the \
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663.6 Q 3.056(ginning. A)-.15 F(ne)3.056 E -.05(ga)-.15 G(ti).05 E -.15
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128 687.6 Q F1("\\0")2.5 E F0
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(alue in)-.25 F(scalar conte)128 184.8 Q
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202.8 R .143(re planning to \214letest the return v)-.5 F .143
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2.643(db)-.5 G .143(etter prepend the directory in)-2.643 F 2.5
(question. Otherwise,)128 214.8 R(because we didn')2.5 E(t)-.18 E F2
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(opendir\(my $dh, $some_dir\) || die "can\010t opendir $some_dir: $!";)
152 232.8 Q
(@dots = grep { /^\\./ && \255f "$some_dir/$_" } readdir\($dh\);)152
244.8 Q(closedir $dh;)152 256.8 Q F0
(As of Perl 5.11.2 you can use a bare)128 274.8 Q F2(readdir)2.5 E F0
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(while\(readdir $dh\) {)152 304.8 Q(print "$some_dir/$_\\n";)176 316.8 Q
(})152 328.8 Q(closedir $dh;)152 340.8 Q F0(readline)108 357.6 Q F3
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447.6 Q F2($/)3.162 E F0 .662(is set to)3.162 F F2(undef)3.162 E F0
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(This is the internal function implementing the)128 477.6 R F2(<EXPR>)
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(<EXPR>)128 489.6 Q F0(operator is discussed in more detail in `)2.5 E
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1.982(will be set with the corresponding error)4.482 F 2.654
(message. It)128 549.6 R .154(can be helpful to check)2.654 F F2($!)
2.653 E F0 .153(when you are reading from \214lehandles you don')2.653 F
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F0 .109(and dies if the result is)2.609 F(not de\214ned.)128 573.6 Q F2
(while \( ! eof\($fh\) \) {)152 591.6 Q
(defined\( $_ = <$fh> \) or die "readline failed: $!";)176 603.6 Q(...)
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3.481 E F0 .981(errors that w)3.481 F .981(ay with the)-.1 F F2(ARGV)
3.481 E F0 .981(\214lehandle. In that case,)3.481 F(you ha)128 657.6 Q
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Q(while \( ! eof\($fh\) \) {)176 711.6 Q(defined\( $_ = <$fh> \))200
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(cuted as a system command.).15 F .735
(The collected standard output of the command is returned.)5.735 F .35
(In scalar conte)128 225.6 R .35
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(\). This)B 1.759(is the)4.259 F .432
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(characters of data into v)5.081 F(ariable)-.25 E F2(SCALAR)128 302.4 Q
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(\214lehandle.)4.535 E F2(SCALAR)7.035 E F0 2.035(will be gro)4.535 F
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(he same \215ags as the system call of the same name.)-3.283 F .782
(Returns the address of the)5.783 F 1.822(sender if)128 326.4 R F2
(SOCKET)4.322 E F0 2.922 -.55('s p)D 1.822
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(epending on the status of the sock)-4.481 F 1.982
(et, either \(8\255bit\) bytes or characters are)-.1 F(recei)128 380.4 Q
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(binmode\(\))128 392.4 Q F0 .695(to operate with the)3.195 F F1
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404.4 R .04(Similarly for the)5.04 F F1(:encoding)2.54 E F0(pragma:)2.54
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(LINE: while \(<STDIN>\) {)152 523.2 Q
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(while \(<STDIN>\) {)200 583.2 Q(if \(/}/\) {)224 595.2 Q 6(#e)12 G
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679.2 Q(redo)128 697.2 Q F0 .081
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F0 2.496(is not)4.996 F(speci\214ed,)128 142.8 Q F1($_)4.808 E F0 2.307
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(alue returned depends on the type of thing the reference is a)-.25 F
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172.8 Q(ARRAY)152 184.8 Q(HASH)152 196.8 Q(CODE)152 208.8 Q(REF)152
220.8 Q(GLOB)152 232.8 Q(LVALUE)152 244.8 Q(FORMAT)152 256.8 Q(IO)152
268.8 Q(VSTRING)152 280.8 Q(Regexp)152 292.8 Q F0 .757(If the reference\
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(print "r is a reference to a hash.\\n";)176 352.8 Q(})152 364.8 Q
(unless \(ref\($r\)\) {)152 376.8 Q
(print "r is not a reference at all.\\n";)176 388.8 Q(})152 400.8 Q F0
.889(The return v)128 418.8 R(alue)-.25 E F1(LVALUE)3.389 E F0 .888
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(taking the reference of function calls lik)128 430.8 R(e)-.1 E F1
(pos\(\))5.254 E F0(or)5.254 E F1(substr\(\))5.254 E F0(.)A F1(VSTRING)
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442.8 Q(ersion string.)-.15 E(The result)128 460.8 Q F1(Regexp)2.5 E F0
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(xisting \214le)-.15 F F2(NEWN)3.418 E(AME)-.315 E F0 .918
(will be clobbered.)3.418 F .918(Returns true for success,)5.918 F -.1
(fa)128 519.6 S(lse otherwise.).1 E(Beha)128 537.6 Q 1.281
(vior of this function v)-.2 F 1.282
(aries wildly depending on your system implementation.)-.25 F -.15(Fo)
6.282 G 3.782(re).15 G 1.282(xample, it)-3.932 F .518
(will usually not w)128 549.6 R .518
(ork across \214le system boundaries, e)-.1 F -.15(ve)-.25 G 3.018(nt)
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(orks on directories, open \214les, or pre-)-.1 F -.15(ex)128 573.6 S
.535(isting \214les.).15 F .535(Check perlport and either the)5.535 F F3
-.37(re)3.034 G(name).37 E F0 .534(\(2\) manpage or equi)1.666 F -.25
(va)-.25 G .534(lent system documentation).25 F(for details.)128 585.6 Q
-.15(Fo)128 603.6 S 2.5(rap).15 G(latform independent)-2.5 E F1(move)2.5
E F0(function look at the File::Cop)2.5 E 2.5(ym)-.1 G(odule.)-2.5 E
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(foreach $prefix \(@INC\) {)194 318 Q
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5.772 F 2.151(number of semaphore operations.)128 326.4 R 2.151
(Returns true if successful, f)7.151 F 2.151(alse on error)-.1 F 7.15
(.A)-.55 G 4.65(sa)-7.15 G 4.65(ne)-4.65 G 2.15(xample, the)-4.8 F
(follo)128 338.4 Q(wing code w)-.25 E(aits on semaphore)-.1 E F2
($semnum)2.5 E F0(of semaphore id)2.5 E F2($semid:)2.5 E
($semop = pack\("s!3", $semnum, \2551, 0\);)152 356.4 Q
(die "Semaphore trouble: $!\\n" unless semop\($semid, $semop\);)152
368.4 Q F0 3.303 -.8(To s)128 386.4 T 1.703
(ignal the semaphore, replace).8 F F2<ad31>4.204 E F0(with)4.204 E F2(1)
4.204 E F0 6.704(.S)C 1.704(ee also `)-6.704 F(`SysV)-.74 E F3(IPC)4.204
E F0 3.184 -.74('' i)D 4.204(np).74 G(erlipc,)-4.204 E F2(IPC::SysV)
4.204 E F0 4.204(,a)C(nd)-4.204 E F2(IPC::SysV::Semaphore)128 398.4 Q F0
(documentation.)2.5 E(send)108 415.2 Q F3(SOCKET)2.5 E F0(,MSG,FLA)A
(GS,T)-.4 E(O)-.18 E(send)108 427.2 Q F3(SOCKET)2.5 E F0(,MSG,FLA)A(GS)
-.4 E .585(Sends a message on a sock)128 439.2 R 3.085(et. Attempts)-.1
F .584(to send the scalar)3.085 F F3(MSG)3.084 E F0 .584(to the)3.084 F
F3(SOCKET)3.084 E F0 3.084(\214lehandle. T)3.084 F(ak)-.8 E .584(es the)
-.1 F 2.479(same \215ags as the system call of the same name.)128 451.2
R 2.479(On unconnected sock)7.479 F 2.479(ets, you must specify a)-.1 F
1.223(destination to)128 463.2 R F4 1.223(send to)3.723 F F0 3.723(,i)C
3.723(nw)-3.723 G 1.223(hich case it does a)-3.723 F F4(sendto)3.723 E
F0 1.223(\(2\) syscall.)1.666 F 1.222(Returns the number of characters)
6.223 F .123(sent, or the unde\214ned v)128 475.2 R .123(alue on error)
-.25 F 5.123(.T)-.55 G(he)-5.123 E F4(sendmsg)2.623 E F0 .123
(\(2\) syscall is currently unimplemented.)1.666 F .123(See `)5.123 F(`)
-.74 E F3(UDP:)A F0(Message P)128 487.2 Q(assing')-.15 E 2.5('i)-.74 G
2.5(np)-2.5 G(erlipc for e)-2.5 E(xamples.)-.15 E .539(Note the)128
505.2 R F4 -.15(ch)3.039 G(ar).15 E(acter)-.15 E(s)-.1 E F0 3.038(:d)C
.538(epending on the status of the sock)-3.038 F .538
(et, either \(8\255bit\) bytes or characters are sent.)-.1 F 2.583
(By def)128 517.2 R 2.583(ault all sock)-.1 F 2.583
(ets operate on bytes, b)-.1 F 2.583(ut for e)-.2 F 2.583
(xample if the sock)-.15 F 2.583(et has been changed using)-.1 F F4
(binmode\(\))128 529.2 Q F0 1.612(to operate with the)4.112 F F2
(:encoding\(utf8\))4.112 E F0 1.611(I/O layer \(see `)4.112 F(`open')
-.74 E 1.611(', or the)-.74 F F2(open)4.111 E F0(pragma,)4.111 E 2.456
(open\), the I/O will operate on)128 541.2 R F3(UTF\2558)4.956 E F0
2.456(encoded Unicode characters, not bytes.)4.956 F 2.456
(Similarly for the)7.456 F F2(:encoding)128 553.2 Q F0
(pragma: in that case pretty much an)2.5 E 2.5(yc)-.15 G
(haracters can be sent.)-2.5 E(setpgrp)108 570 Q F3(PID)2.5 E F0(,PGRP)A
1.098(Sets the current process group for the speci\214ed)128 582 R F3
(PID)3.598 E F0(,)A F2(0)3.598 E F0 1.098(for the current process.)3.598
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(when used on a machine that doesn')128 594 R 5.385(ti)-.18 G(mplement)
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(ar)128 606 Q .113(guments are omitted, it def)-.18 F .113(aults to)-.1
F F2(0,0)2.613 E F0 5.113(.N)C .113(ote that the)-5.113 F F3(BSD)2.613 E
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(does not accept)2.612 F(an)128 618 Q 2.5(ya)-.15 G -.18(rg)-2.5 G
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(See also)5 E F2(POSIX::setsid\(\))2.5 E F0(.)A(setpriority)108 634.8 Q
F3(WHICH)2.5 E F0(,WHO,PRIORITY)A 1.588
(Sets the current priority for a process, a process group, or a user)128
646.8 R 6.589(.\()-.55 G(See)-6.589 E F4(setpriority)4.089 E F0 4.089
(\(2\).\) Raises)1.666 F(an)4.089 E -.15(ex)128 658.8 S
(ception when used on a machine that doesn').15 E 2.5(ti)-.18 G
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-1.35 E 1.485(Sets the sock)128 687.6 R 1.485(et option requested.)-.1 F
(Returns)6.484 E F2(undef)3.984 E F0 1.484(on error)3.984 F 6.484(.U)
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(vided by the)-.15 F F2(Socket)128 699.6 Q F0 4.315(module for)6.815 F
F3(LEVEL)6.815 E F0(and)6.815 E F3(OPN)6.815 E(AME)-.315 E F0 9.315(.V)C
4.315(alues for)-10.425 F F3(LEVEL)6.815 E F0 4.316
(can also be obtained from)6.815 F(getprotobyname.)128 711.6 Q F3(OPTV)
7.222 E(AL)-1.215 E F0 2.222(might either be a pack)4.722 F 2.222
(ed string or an inte)-.1 F(ger)-.15 E 7.222(.A)-.55 G 4.722(ni)-7.222 G
(nte)-4.722 E(ger)-.15 E F3(OPTV)4.722 E(AL)-1.215 E F0(is)4.722 E
(shorthand for pack\(`)128 723.6 Q(`i')-.74 E(',)-.74 E F3(OPTV)2.5 E
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(Shifts the \214rst v)128 166.8 R .805(alue of the array of)-.25 F 3.305
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(wn. If)-.25 F .663(there are no elements in the array)3.164 F 3.163(,r)
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(xical scope of subroutines and formats, and the)-.15 F F1(@ARGV)4.233 E
F0 1.733(array outside a)4.233 F .616(subroutine and also within the le)
128 202.8 R .616(xical scopes established by the)-.15 F F1 .615
(eval STRING)3.116 F F0(,)A F1 .615(BEGIN {})3.115 F F0(,)A F1(INIT)
3.115 E({})128 214.8 Q F0(,)A F1(CHECK {})2.5 E F0(,)A F1(UNITCHECK {})
2.5 E F0 2.5(,a)C(nd)-2.5 E F1(END {})2.5 E F0(constructs.)2.5 E .604
(Starting with Perl 5.14,)128 232.8 R F1(shift)3.104 E F0 .604(can tak)
3.104 F 3.104(eas)-.1 G(calar)-3.104 E F2(EXPR)3.104 E F0 3.105(,w)C
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Q 5.724(.T)-.65 G .723(he ar)-5.724 F .723
(gument will be dereferenced automatically)-.18 F 5.723(.T)-.65 G .723
(his aspect of)-5.723 F F1(shift)3.223 E F0 .723(is considered highly)
3.223 F -.15(ex)128 256.8 S 2.5(perimental. The).15 F -.15(ex)2.5 G
(act beha).15 E(viour may change in a future v)-.2 E(ersion of Perl.)
-.15 E .705(See also)128 274.8 R F1(unshift)3.205 E F0(,)A F1(push)3.205
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(and)3.205 E F1(unshift)3.205 E F0 .706
(do the same thing to the left end of an)3.206 F(array that)128 286.8 Q
F1(pop)2.5 E F0(and)2.5 E F1(push)2.5 E F0(do to the right end.)2.5 E
(shmctl)108 303.6 Q F2(ID)2.5 E F0(,CMD,ARG)A(Calls the System V)128
315.6 Q F2(IPC)2.5 E F0(function shmctl.)2.5 E -1.1(Yo)5 G(u')1.1 E
(ll probably ha)-.1 E .3 -.15(ve t)-.2 H 2.5(os).15 G(ay)-2.5 E F1
(use IPC::SysV;)152 333.6 Q F0 .739
(\214rst to get the correct constant de\214nitions.)128 351.6 R(If)5.739
E F2(CMD)3.239 E F0(is)3.239 E F1(IPC_STAT)3.239 E F0 3.239(,t)C(hen)
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2.547(structure. Returns)2.547 F(lik)2.547 E 2.547(ei)-.1 G(octl:)-2.547
E F1(undef)2.547 E F0 .047(for error; ")2.547 F F1(0)A F0 -.2(bu)2.547 G
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(and the actual return v)128 375.6 R 4.441(alue otherwise.)-.25 F 4.441
(See also `)9.441 F(`SysV)-.74 E F2(IPC)6.941 E F0 5.921 -.74('' i)D
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(documentation.)128 387.6 Q(shmget)108 404.4 Q F2(KEY)2.5 E F0
(,SIZE,FLA)A(GS)-.4 E .337(Calls the System V)128 416.4 R F2(IPC)2.837 E
F0 .337(function shmget.)2.837 F .337(Returns the shared memory se)5.337
F .337(gment id, or)-.15 F F1(undef)2.838 E F0 .338(on error)2.838 F(.)
-.55 E(See also `)128 428.4 Q(`SysV)-.74 E F2(IPC)2.5 E F0 1.48 -.74
('' i)D 2.5(np).74 G(erlipc and)-2.5 E F1(IPC::SysV)2.5 E F0
(documentation.)2.5 E(shmread)108 445.2 Q F2(ID)2.5 E F0(,V)A
(AR,POS,SIZE)-1.35 E(shmwrite)108 457.2 Q F2(ID)2.5 E F0
(,STRING,POS,SIZE)A 1.126(Reads or writes the System V shared memory se)
128 469.2 R(gment)-.15 E F2(ID)3.625 E F0 1.125(starting at position)
3.625 F F2(POS)3.625 E F0 1.125(for size)3.625 F F2(SIZE)3.625 E F0(by)
3.625 E .336(attaching to it, cop)128 481.2 R .336
(ying in/out, and detaching from it.)-.1 F .336(When reading,)5.336 F F2
-1.215(VA)2.836 G(R)1.215 E F0 .337(must be a v)2.836 F .337
(ariable that will)-.25 F .672(hold the data read.)128 493.2 R .671
(When writing, if)5.672 F F2(STRING)3.171 E F0 .671(is too long, only)
3.171 F F2(SIZE)3.171 E F0 .671(bytes are used; if)3.171 F F2(STRING)
3.171 E F0 .671(is too)3.171 F .157
(short, nulls are written to \214ll out)128 505.2 R F2(SIZE)2.658 E F0
2.658(bytes. Return)2.658 F .158(true if successful, f)2.658 F .158
(alse on error)-.1 F(.)-.55 E/F3 10/Times-Italic@0 SF(shmr)5.158 E
(ead\(\))-.37 E F0(taints)2.658 E .009(the v)128 517.2 R .008
(ariable. See also `)-.25 F(`SysV)-.74 E F2(IPC)2.508 E F0 1.488 -.74
('' i)D 2.508(np).74 G(erlipc,)-2.508 E F1(IPC::SysV)2.508 E F0 2.508
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(module from)2.508 F F2(CP)128 529.2 Q(AN)-.828 E F0(.)A(shutdo)108 546
Q(wn)-.25 E F2(SOCKET)2.5 E F0(,HO)A(W)-.35 E .059(Shuts do)128 558 R
.059(wn a sock)-.25 F .059(et connection in the manner indicated by)-.1
F F2(HO)2.56 E(W)-.315 E F0 2.56(,w)C .06
(hich has the same interpretation as)-2.56 F
(in the syscall of the same name.)128 570 Q F1(shutdown\(SOCKET, 0\);)
152 588 Q 6(#I)24 G(/we have stopped reading data)-6 E
(shutdown\(SOCKET, 1\);)152 600 Q 6(#I)24 G
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(This is useful with sock)128 630 R 1.49(ets when you w)-.1 F 1.49
(ant to tell the other side you')-.1 F 1.49(re done writing b)-.5 F 1.49
(ut not done)-.2 F 2.352(reading, or vice v)128 642 R 4.852(ersa. It')
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.167(for success; on error)2.667 F 2.667(,r)-.4 G(eturns)-2.667 E F1
(undef)2.667 E F0 .167(if the \214rst ar)2.667 F .166(gument is not a v)
-.18 F .166(alid \214lehandle, or returns)-.25 F F1(0)128 684 Q F0
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(ailure.)-.1 E(sin)108 700.8 Q F2(EXPR)2.5 E F0(sin)108 712.8 Q
(Returns the sine of)128 712.8 Q F2(EXPR)2.5 E F0(\(e)2.5 E
(xpressed in radians\).)-.15 E(If)5 E F2(EXPR)2.5 E F0
(is omitted, returns sine of)2.5 E F1($_)2.5 E F0(.)A -.15(Fo)128 730.8
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(EXPR)2.969 E F0 .469(seconds, or fore)2.969 F -.15(ve)-.25 G 2.969(ri)
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128 136.8 Q(ger number of seconds actually slept.)-.15 E
(May be interrupted if the process recei)128 154.8 Q -.15(ve)-.25 G 2.5
(sas).15 G(ignal such as)-2.5 E F1(SIGALRM)2.5 E F0(.)A F1(eval {)152
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F0 -1.1(Yo)128 238.8 S 4.622(up)1.1 G 2.122(robably cannot mix)-4.622 F
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requested, depending on)128 268.8 R(ho)128 280.8 Q 2.631(wi)-.25 G 2.631
(tc)-2.631 G .131(ounts seconds.)-2.631 F .131(Most modern systems al)
5.131 F -.1(wa)-.1 G .131(ys sleep the full amount.).1 F(The)5.13 E 2.63
(ym)-.15 G .13(ay appear to sleep)-2.63 F 2.812(longer than that, ho)128
292.8 R(we)-.25 E -.15(ve)-.25 G 3.612 -.4(r, b).15 H 2.812
(ecause your process might not be scheduled right a).4 F -.1(wa)-.15 G
5.312(yi).1 G 5.312(nab)-5.312 G(usy)-5.512 E(multitasking system.)128
304.8 Q -.15(Fo)128 322.8 S 3.844(rd).15 G 1.344
(elays of \214ner granularity than one second, the T)-3.844 F 1.344
(ime::HiRes module \(from)-.35 F F2(CP)3.844 E(AN)-.828 E F0 3.844(,a)C
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E F0 7.025(.Y)C 2.025(ou may also use Perl')-8.125 F 4.525(sf)-.55 G
(our)-4.525 E(-)-.2 E(ar)128 346.8 Q .816(gument v)-.18 F .816
(ersion of)-.15 F F3(select\(\))3.316 E F0(lea)3.316 E .816
(ving the \214rst three ar)-.2 F .815
(guments unde\214ned, or you might be able to use)-.18 F(the)128 358.8 Q
F1(syscall)2.5 E F0(interf)2.5 E(ace to access)-.1 E F3(setitimer)2.5 E
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-.1 E(See also the)128 376.8 Q F2(POSIX)2.5 E F0(module')2.5 E(s)-.55 E
F1(pause)2.5 E F0(function.)2.5 E(sock)108 393.6 Q(et)-.1 E F2(SOCKET)
2.5 E F0(,DOMAIN,TYPE,PR)A -1.88 -.4(OT O)-.4 H(COL).4 E 1.787
(Opens a sock)128 405.6 R 1.788
(et of the speci\214ed kind and attaches it to \214lehandle)-.1 F F2
(SOCKET)4.288 E F0(.)A F2(DOMAIN)6.788 E F0(,)A F2(TYPE)4.288 E F0 4.288
(,a)C(nd)-4.288 E F2(PR)128 417.6 Q -1.692 -.36(OT O)-.36 H(COL).36 E F0
1.086(are speci\214ed the same as for the syscall of the same name.)
3.586 F -1.1(Yo)6.085 G 3.585(us)1.1 G(hould)-3.585 E F1 1.085
(use Socket)3.585 F F0 4.986
(\214rst to get the proper de\214nitions imported.)128 429.6 R 4.986
(See the e)9.986 F 4.986(xamples in `)-.15 F(`Sock)-.74 E 4.986
(ets: Client/Serv)-.1 F(er)-.15 E(Communication')128 441.6 Q 2.5('i)-.74
G 2.5(np)-2.5 G(erlipc.)-2.5 E 1.179
(On systems that support a close-on-e)128 459.6 R -.15(xe)-.15 G 3.679
<638d>.15 G 1.178(ag on \214les, the \215ag will be set for the ne)
-3.679 F 1.178(wly opened \214le)-.25 F(descriptor)128 471.6 Q 2.5(,a)
-.4 G 2.5(sd)-2.5 G(etermined by the v)-2.5 E(alue of $^F)-.25 E 5(.S)
-.8 G(ee `)-5 E(`$^F')-.74 E 2.5('i)-.74 G 2.5(np)-2.5 G(erlv)-2.5 E(ar)
-.25 E(.)-.55 E(sock)108 488.4 Q(etpair)-.1 E F2(SOCKET1)2.5 E F0
(,SOCKET2,DOMAIN,TYPE,PR)A -1.88 -.4(OT O)-.4 H(COL).4 E .955
(Creates an unnamed pair of sock)128 500.4 R .955
(ets in the speci\214ed domain, of the speci\214ed type.)-.1 F F2
(DOMAIN)5.956 E F0(,)A F2(TYPE)3.456 E F0(,)A(and)128 512.4 Q F2(PR)
3.067 E -1.692 -.36(OT O)-.36 H(COL).36 E F0 .567
(are speci\214ed the same as for the syscall of the same name.)3.067 F
.566(If unimplemented, raises)5.567 F(an e)128 524.4 Q 2.5
(xception. Returns)-.15 F(true if successful.)2.5 E 1.178
(On systems that support a close-on-e)128 542.4 R -.15(xe)-.15 G 3.678
<638d>.15 G 1.178(ag on \214les, the \215ag will be set for the ne)
-3.678 F 1.179(wly opened \214le)-.25 F
(descriptors, as determined by the v)128 554.4 Q(alue of $^F)-.25 E 5
(.S)-.8 G(ee `)-5 E(`$^F')-.74 E 2.5('i)-.74 G 2.5(np)-2.5 G(erlv)-2.5 E
(ar)-.25 E(.)-.55 E 1.249(Some systems de\214ned)128 572.4 R F1(pipe)
3.749 E F0 1.249(in terms of)3.749 F F1(socketpair)3.749 E F0 3.749(,i)C
3.749(nw)-3.749 G 1.248(hich a call to)-3.749 F F1 1.248
(pipe\(Rdr, Wtr\))3.748 F F0(is)3.748 E(essentially:)128 584.4 Q F1
(use Socket;)152 602.4 Q
(socketpair\(Rdr, Wtr, AF_UNIX, SOCK_STREAM, PF_UNSPEC\);)152 614.4 Q
(shutdown\(Rdr, 1\);)152 626.4 Q 6(#n)48 G 6(om)-6 G
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2.153(depending on ho)128 150 R 4.653(wt)-.25 G 2.153
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($a[$i] = $y)152 204 Q(splice\(@a,$i,1,$y\))54 E F0
(Example, assuming array lengths are passed before arrays:)128 222 Q F2
(sub aeq {)152 240 Q 6(#c)12 G(ompare two list values)-6 E
(my\(@a\) = splice\(@_,0,shift\);)176 252 Q
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324 Q(})152 336 Q(if \(&aeq\($len,@foo[1..$len],0+@bar,@bar\)\) { ... })
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-.828(PA)3.111 G(TTERN)-.171 E F0 .61(is tak)3.111 F .61
(en to be a delimiter separating)-.1 F(the \214elds.)128 538.8 Q
(\(Note that the delimiter may be longer than one character)5 E(.\))-.55
E(If)128 556.8 Q F1(LIMIT)3.119 E F0 .619(is speci\214ed and positi)
3.119 F -.15(ve)-.25 G 3.119(,i).15 G 3.119(tr)-3.119 G .62
(epresents the maximum number of \214elds the)-3.119 F F1(EXPR)3.12 E F0
.62(will be split)3.12 F .781(into, though the actual number of \214eld\
s returned depends on the number of times)128 568.8 R F1 -.828(PA)3.28 G
(TTERN)-.171 E F0(matches)3.28 E(within)128 580.8 Q F1(EXPR)2.77 E F0
5.27(.I)C(f)-5.27 E F1(LIMIT)2.77 E F0 .27(is unspeci\214ed or zero, tr\
ailing null \214elds are stripped \(which potential users of)2.77 F F2
(pop)128 592.8 Q F0 -.1(wo)2.557 G .057(uld do well to remember\).).1 F
(If)5.057 E F1(LIMIT)2.557 E F0 .057(is ne)2.557 F -.05(ga)-.15 G(ti).05
E -.15(ve)-.25 G 2.557(,i).15 G 2.556(ti)-2.557 G 2.556(st)-2.556 G .056
(reated as if an arbitrarily lar)-2.556 F(ge)-.18 E F1(LIMIT)2.556 E F0
(had)2.556 E .052(been speci\214ed.)128 604.8 R .053
(Note that splitting an)5.052 F F1(EXPR)2.553 E F0 .053(that e)2.553 F
-.25(va)-.25 G .053(luates to the empty string al).25 F -.1(wa)-.1 G
.053(ys returns the empty).1 F(list, re)128 616.8 Q -.05(ga)-.15 G
(rdless of the).05 E F1(LIMIT)2.5 E F0(speci\214ed.)2.5 E 3.104(Ap)128
634.8 S .604(attern matching the empty string \(not to be confused with\
 an empty pattern)-3.104 F F2(//)3.104 E F0 3.104(,w)C .603
(hich is just one)-3.104 F .518
(member of the set of patterns matching the epmty string\), splits)128
646.8 R F1(EXPR)3.018 E F0 .518(into indi)3.018 F .518
(vidual characters.)-.25 F -.15(Fo)5.518 G(r).15 E -.15(ex)128 658.8 S
(ample:).15 E F2
(print join\(\010:\010, split\(/ */, \010hi there\010\)\), "\\n";)152
676.8 Q F0(produces the output 'h:i:t:h:e:r:e'.)128 694.8 Q .049
(As a special case for)128 712.8 R F2(split)2.549 E F0 2.549(,t)C .049
(he empty pattern)-2.549 F F2(//)2.549 E F0 .049
(speci\214cally matches the empty string; this is not be)2.549 F 1.255(\
confused with the normal use of an empty pattern to mean the last succe\
ssful match.)128 724.8 R 1.256(So to split a)6.256 F(perl v5.14.2)72 768
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128 84 Q(vidual characters, the follo)-.25 E(wing:)-.25 E/F1 10
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(print join\(\010:\010, split\(//, \010hi there\010\)\), "\\n";)152 102
Q F0(produces the output 'h:i: :t:h:e:r:e'.)128 120 Q 1.854
(Empty leading \214elds are produced when there are positi)128 138 R
-.15(ve)-.25 G 1.853(-width matches at the be).15 F 1.853
(ginning of the)-.15 F(string; a zero-width match at the be)128 150 Q
(ginning of the string does not produce an empty \214eld. F)-.15 E(or e)
-.15 E(xample:)-.15 E F1
(print join\(\010:\010, split\(/\(?=\\w\)/, \010hi there!\010\)\);)146
168 Q F0 .545(produces the output 'h:i :t:h:e:r:e!'. Empty trailing \
\214elds, on the other hand, are produced when there)128 186 R .563
(is a match at the end of the string \(and when)128 198 R/F2 9
/Times-Roman@0 SF(LIMIT)3.063 E F0 .563(is gi)3.063 F -.15(ve)-.25 G
3.063(na).15 G .563(nd is not 0\), re)-3.063 F -.05(ga)-.15 G .563
(rdless of the length of).05 F(the match.)128 210 Q -.15(Fo)5 G 2.5(re)
.15 G(xample:)-2.65 E F1(print join\(\010:\010, split\(//,)146 228 Q
(\010hi there!\010, \2551\)\), "\\n";)18 E(print join\(\010:\010, split\
\(/\\W/, \010hi there!\010, \2551\)\), "\\n";)146 240 Q F0
(produce the output 'h:i: :t:h:e:r:e:!:' and 'hi:there:', respecti)128
258 Q -.15(ve)-.25 G(ly).15 E 2.5(,b)-.65 G
(oth with an empty trailing \214eld.)-2.5 E(The)128 276 Q F2(LIMIT)2.5 E
F0(parameter can be used to split a line partially)2.5 E F1
(\($login, $passwd, $remainder\) = split\(/:/, $_, 3\);)152 294 Q F0
.059(When assigning to a list, if)128 312 R F2(LIMIT)2.559 E F0 .059
(is omitted, or zero, Perl supplies a)2.559 F F2(LIMIT)2.559 E F0 .059
(one lar)2.559 F .06(ger than the number)-.18 F 1.117(of v)128 324 R
1.117(ariables in the list, to a)-.25 F -.2(vo)-.2 G 1.117
(id unnecessary w).2 F 3.617(ork. F)-.1 F 1.116(or the list abo)-.15 F
-.15(ve)-.15 G F2(LIMIT)3.766 E F0 -.1(wo)3.616 G 1.116(uld ha).1 F
1.416 -.15(ve b)-.2 H 1.116(een 4 by).15 F(def)128 336 Q 2.5(ault. In)
-.1 F(time critical applications it behoo)2.5 E -.15(ve)-.15 G 2.5(sy)
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3.177(If the)128 354 R F2 -.828(PA)5.677 G(TTERN)-.171 E F0 3.177(conta\
ins parentheses, additional list elements are created from each matchin\
g)5.677 F(substring in the delimiter)128 366 Q(.)-.55 E F1
(split\(/\([,\255]\)/, "1\25510,20", 3\);)152 384 Q F0
(produces the list v)128 402 Q(alue)-.25 E F1
(\(1, \010\255\010, 10, \010,\010, 20\))152 420 Q F0 .617
(If you had the entire header of a normal Unix email message in)128 438
R F1($header)3.116 E F0 3.116(,y)C .616(ou could split it up into)-3.116
F(\214elds and their v)128 450 Q(alues this w)-.25 E(ay:)-.1 E F1
($header =~ s/\\n\(?=\\s\)//g;)152 468 Q 6(#f)12 G
(ix continuation lines)-6 E 12(%hdrs =)152 480 R
(\(UNIX_FROM => split /^\(\\S*?\):\\s*/m, $header\);)12 E F0 .342
(The pattern)128 498 R F1(/PATTERN/)2.842 E F0 .343
(may be replaced with an e)2.842 F .343
(xpression to specify patterns that v)-.15 F .343(ary at runtime.)-.25 F
(\(T)128 510 Q 2.5(od)-.8 G 2.5(or)-2.5 G
(untime compilation only once, use)-2.5 E F1(/$variable/o)2.5 E F0(.\))A
.012(As a special case, specifying a)128 528 R F2 -.828(PA)2.512 G
(TTERN)-.171 E F0 .012(of space \()2.512 F F1<08c22008>A F0 2.512(\)w)C
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2.512 E 1.025(no ar)128 540 R 1.025(guments does.)-.18 F(Thus,)6.025 E
F1(split\(\010\302 \010\))3.525 E F0 1.025(can be used to emulate)3.525
F/F3 10/Times-Bold@0 SF(awk)3.526 E F0 2.126 -.55('s d)D(ef).55 E 1.026
(ault beha)-.1 F(vior)-.2 E 3.526(,w)-.4 G(hereas)-3.526 E F1
(split\(/\302 /\))128 552 Q F0 .308(will gi)2.808 F .608 -.15(ve y)-.25
H .308(ou as man).15 F 2.808(yi)-.15 G .307
(nitial null \214elds \(empty string\) as there are leading spaces.)
-2.808 F(A)5.307 E F1(split)128 564 Q F0(on)3.281 E F1(/\\s+/)3.281 E F0
.781(is lik)3.281 F 3.281(ea)-.1 G F1(split\(\010\302 \010\))A F0 -.15
(ex)3.281 G .781(cept that an).15 F 3.281(yl)-.15 G .782
(eading whitespace produces a null \214rst)-3.281 F 2.5(\214eld. A)128
576 R F1(split)2.5 E F0(with no ar)2.5 E(guments really does a)-.18 E F1
(split\(\010\302 \010,\302 $_\))2.5 E F0(internally)2.5 E(.)-.65 E(A)128
594 Q F2 -.828(PA)2.5 G(TTERN)-.171 E F0(of)2.5 E F1(/^/)2.5 E F0
(is treated as if it were)2.5 E F1(/^/m)2.5 E F0 2.5(,s)C(ince it isn')
-2.5 E 2.5(tm)-.18 G(uch use otherwise.)-2.5 E(Example:)128 612 Q F1
(open\(PASSWD, \010/etc/passwd\010\);)152 630 Q(while \(<PASSWD>\) {)152
642 Q(chomp;)176 654 Q(\($login, $passwd, $uid, $gid,)176 666 Q
($gcos, $home, $shell\) = split\(/:/\);)182 678 Q(#...)176 690 Q(})152
702 Q F0 .506(As with re)128 720 R .506(gular pattern matching, an)-.15
F 3.006(yc)-.15 G .506(apturing parentheses that are not matched in a)
-3.006 F F1(split\(\))3.006 E F0(will)3.006 E(perl v5.14.2)72 768 Q
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F1(sprintf)2.602 E F0 5.102(.S)C(ee)-5.102 E(belo)128 154.8 Q 3.194(wf)
-.25 G .694(or more details and see)-3.194 F F1(sprintf\(3\))3.193 E F0
(or)3.193 E F1(printf\(3\))3.193 E F0 .693(on your system for an e)3.193
F .693(xplanation of)-.15 F(the general principles.)128 166.8 Q -.15(Fo)
128 184.8 S 2.5(re).15 G(xample:)-2.65 E F1 6(#F)176 202.8 S
(ormat number with up to 8 leading zeroes)-6 E
($result = sprintf\("%08d", $number\);)176 214.8 Q 6(#R)176 238.8 S
(ound number to 3 digits after decimal point)-6 E
($rounded = sprintf\("%.3f", $number\);)176 250.8 Q F0 .136
(Perl does its o)128 268.8 R(wn)-.25 E F1(sprintf)2.636 E F0 .136
(formatting: it emulates the C function)2.636 F/F3 10/Times-Italic@0 SF
(sprintf)2.637 E F0 .137(\(3\), b)1.666 F .137(ut doesn')-.2 F 2.637(tu)
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(for \215oating-point numbers, and e)128 280.8 R -.15(ve)-.25 G 6.029
(nt).15 G 3.529(hen only standard modi\214ers are allo)-6.029 F 6.029
(wed. Non-standard)-.25 F -.15(ex)128 292.8 S(tensions in your local).15
E F3(sprintf)2.5 E F0(\(3\) are therefore una)1.666 E -.25(va)-.2 G
(ilable from Perl.).25 E(Unlik)128 310.8 Q(e)-.1 E F1(printf)3.267 E F0
(,)A F1(sprintf)3.267 E F0 .767
(does not do what you probably mean when you pass it an array as your)
3.267 F .712(\214rst ar)128 322.8 R .712(gument. The array is gi)-.18 F
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(xt, and instead of using the 0th element of the array as)-.15 F(the fo\
rmat, Perl will use the count of elements in the array as the format, w\
hich is almost ne)128 334.8 Q -.15(ve)-.25 G 2.5(ru).15 G(seful.)-2.5 E
(Perl')128 352.8 Q(s)-.55 E F1(sprintf)2.5 E F0(permits the follo)2.5 E
(wing uni)-.25 E -.15(ve)-.25 G(rsally-kno).15 E(wn con)-.25 E -.15(ve)
-.4 G(rsions:).15 E F1 18(%% a)146 370.8 R(percent sign)6 E 18(%c a)146
382.8 R(character with the given number)6 E 18(%s a)146 394.8 R(string)6
E 18(%d a)146 406.8 R(signed integer, in decimal)6 E 18(%u an)146 418.8
R(unsigned integer, in decimal)6 E 18(%o an)146 430.8 R
(unsigned integer, in octal)6 E 18(%x an)146 442.8 R
(unsigned integer, in hexadecimal)6 E 18(%e a)146 454.8 R
(floating\255point number, in scientific notation)6 E 18(%f a)146 466.8
R(floating\255point number, in fixed decimal notation)6 E 18(%g a)146
478.8 R(floating\255point number, in %e or %f notation)6 E F0
(In addition, Perl permits the follo)128 496.8 Q
(wing widely-supported con)-.25 E -.15(ve)-.4 G(rsions:).15 E F1 18
(%X like)146 514.8 R(%x, but using upper\255case letters)6 E 18(%E like)
146 526.8 R(%e, but using an upper\255case "E")6 E 18(%G like)146 538.8
R(%g, but with an upper\255case "E" \(if applicable\))6 E 18(%b an)146
550.8 R(unsigned integer, in binary)6 E 18(%B like)146 562.8 R
(%b, but using an upper\255case "B" with the # flag)6 E 18(%p a)146
574.8 R(pointer \(outputs the Perl value\010s address in hexadecimal\))6
E 18(%n special:)146 586.8 R
(*stores* the number of characters output so far)6 E
(into the next variable in the parameter list)176 598.8 Q F0(Finally)128
616.8 Q 2.542(,f)-.65 G .042(or backw)-2.542 F .042
(ard \(and we do mean `)-.1 F(`backw)-.74 E(ard')-.1 E .042
('\) compatibility)-.74 F 2.542(,P)-.65 G .043
(erl permits these unnecessary b)-2.542 F(ut)-.2 E(widely-supported con)
128 628.8 Q -.15(ve)-.4 G(rsions:).15 E F1 18(%i a)146 646.8 R
(synonym for %d)6 E 18(%D a)146 658.8 R(synonym for %ld)6 E 18(%U a)146
670.8 R(synonym for %lu)6 E 18(%O a)146 682.8 R(synonym for %lo)6 E 18
(%F a)146 694.8 R(synonym for %f)6 E F0 .418(Note that the number of e)
128 712.8 R .418
(xponent digits in the scienti\214c notation produced by)-.15 F F1(%e)
2.918 E F0(,)A F1(%E)2.918 E F0(,)A F1(%g)2.917 E F0(and)2.917 E F1(%G)
2.917 E F0(for)2.917 E .537(numbers with the modulus of the e)128 724.8
R .537
(xponent less than 100 is system-dependent: it may be three or less)-.15
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(\(zero-padded as necessary\).)128 84 R 1.081(In other w)6.081 F 1.081
(ords, 1.23 times ten to the 99th may be either `)-.1 F(`1.23e99')-.74 E
3.58('o)-.74 G(r)-3.58 E -.74(``)128 96 S(1.23e099').74 E('.)-.74 E
1.833(Between the)128 114 R/F1 10/Courier@0 SF(%)4.333 E F0 1.833
(and the format letter)4.333 F 4.334(,y)-.4 G 1.834(ou may specify se)
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(utes controlling the)-.2 F(interpretation of the format.)128 126 Q
(In order)5 E 2.5(,t)-.4 G(hese are:)-2.5 E(format parameter inde)128
142.8 Q(x)-.15 E .985(An e)148 154.8 R .985
(xplicit format parameter inde)-.15 F .985(x, such as)-.15 F F1(2$)3.485
E F0 3.485(.B)C 3.485(yd)-3.485 G(ef)-3.485 E .984
(ault sprintf will format the ne)-.1 F .984(xt unused)-.15 F(ar)148
166.8 Q(gument in the list, b)-.18 E(ut this allo)-.2 E(ws you to tak)
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(printf \010%2$d %1$d\010, 12, 34;)160 184.8 Q 6(#p)36 G(rints "34 12")
-6 E(printf \010%3$d %d %1$d\010, 1, 2, 3;)160 196.8 Q 6(#p)12 G
(rints "3 1 1")-6 E F0(\215ags)128 213.6 Q(one or more of:)148 225.6 Q
F1 12(space prefix)166 243.6 R(non\255negative number with a space)6 E
42(+p)166 255.6 S(refix non\255negative number with a plus sign)-42 E 42
<ad6c>166 267.6 S(eft\255justify within the field)-42 E 42(0u)166 279.6
S(se zeros, not spaces, to right\255justify)-42 E 42(#e)166 291.6 S
(nsure the leading "0" for any octal,)-42 E
(prefix non\255zero hexadecimal with "0x" or "0X",)214 303.6 Q
(prefix non\255zero binary with "0b" or "0B")214 315.6 Q F0 -.15(Fo)148
333.6 S 2.5(re).15 G(xample:)-2.65 E F1(printf \010<% d>\010,)160 351.6
Q 12(12; #)12 F(prints "< 12>")6 E(printf \010<%+d>\010,)160 363.6 Q 12
(12; #)12 F(prints "<+12>")6 E(printf \010<%6s>\010,)160 375.6 Q 12
(12; #)12 F(prints "<)6 E(12>")24 E(printf \010<%\2556s>\010, 12;)160
387.6 Q 6(#p)18 G(rints "<12)-6 E(>")24 E(printf \010<%06s>\010, 12;)160
399.6 Q 6(#p)18 G(rints "<000012>")-6 E(printf \010<%#o>\010,)160 411.6
Q 12(12; #)12 F(prints "<014>")6 E(printf \010<%#x>\010,)160 423.6 Q 12
(12; #)12 F(prints "<0xc>")6 E(printf \010<%#X>\010,)160 435.6 Q 12
(12; #)12 F(prints "<0XC>")6 E(printf \010<%#b>\010,)160 447.6 Q 12
(12; #)12 F(prints "<0b1100>")6 E(printf \010<%#B>\010,)160 459.6 Q 12
(12; #)12 F(prints "<0B1100>")6 E F0 .117
(When a space and a plus sign are gi)148 477.6 R -.15(ve)-.25 G 2.617
(na).15 G 2.617(st)-2.617 G .117
(he \215ags at once, a plus sign is used to pre\214x a positi)-2.617 F
-.15(ve)-.25 G(number)148 489.6 Q(.)-.55 E F1
(printf \010<%+ d>\010, 12;)160 507.6 Q 6(#p)18 G(rints "<+12>")-6 E
(printf \010<% +d>\010, 12;)160 519.6 Q 6(#p)18 G(rints "<+12>")-6 E F0
.01(When the # \215ag and a precision are gi)148 537.6 R -.15(ve)-.25 G
2.51(ni).15 G 2.51(nt)-2.51 G(he)-2.51 E F1(%o)2.51 E F0(con)2.51 E -.15
(ve)-.4 G .01(rsion, the precision is incremented if it').15 F(s)-.55 E
(necessary for the leading `)148 549.6 Q(`0')-.74 E('.)-.74 E F1
(printf \010<%#.5o>\010, 012;)160 567.6 Q 6(#p)36 G(rints "<00012>")-6 E
(printf \010<%#.5o>\010, 012345;)160 579.6 Q 6(#p)18 G(rints "<012345>")
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F0 -.15(ve)128 608.4 S(ctor \215ag).15 E .116
(This \215ag tells Perl to interpret the supplied string as a v)148
620.4 R .117(ector of inte)-.15 F .117(gers, one for each character in)
-.15 F .929(the string. Perl applies the format to each inte)148 632.4 R
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(separator \(a dot)148 644.4 R F1(.)3.51 E F0 1.01(by def)3.51 F 1.01
(ault\). This can be useful for displaying ordinal v)-.1 F 1.01
(alues of characters in)-.25 F(arbitrary strings:)148 656.4 Q F1
(printf "%vd", "AB\\x{100}";)160 674.4 Q 6(#p)66 G(rints "65.66.256")-6
E(printf "version is v%vd\\n", $^V;)160 686.4 Q 6(#P)30 G
(erl\010s version)-6 E F0(Put an asterisk)148 704.4 Q F1(*)2.5 E F0
(before the)2.5 E F1(v)2.5 E F0(to o)2.5 E -.15(ve)-.15 G
(rride the string to use to separate the numbers:).15 E(perl v5.14.2)72
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(Pv6 address)-6 E(printf "bits are %0*v8b\\n", " ", $bits;)160 96 Q 6
(#r)18 G(andom bitstring)-6 E F0 -1.1(Yo)148 114 S 3.49(uc)1.1 G .99
(an also e)-3.49 F .99(xplicitly specify the ar)-.15 F .99
(gument number to use for the join string using something)-.18 F(lik)148
126 Q(e)-.1 E F1(*2$v)2.5 E F0 2.5(;f)C(or e)-2.5 E(xample:)-.15 E F1
(printf \010%*4$vX %*4$vX %*4$vX\010, @addr[1..3], ":";)160 144 Q 6(#3I)
18 G(Pv6 addresses)-6 E F0(\(minimum\) width)128 160.8 Q(Ar)148 172.8 Q
.787(guments are usually formatted to be only as wide as required to di\
splay the gi)-.18 F -.15(ve)-.25 G 3.288(nv).15 G .788(alue. Y)-3.538 F
(ou)-1.1 E .682(can o)148 184.8 R -.15(ve)-.15 G .681
(rride the width by putting a number here, or get the width from the ne)
.15 F .681(xt ar)-.15 F .681(gument \(with)-.18 F F1(*)148 196.8 Q F0
2.5(\)o)C 2.5(rf)-2.5 G(rom a speci\214ed ar)-2.5 E(gument \(e.g., with)
-.18 E F1(*2$)2.5 E F0(\):)A F1(printf "<%s>", "a";)160 214.8 Q 6(#p)42
G(rints "<a>")-6 E(printf "<%6s>", "a";)160 226.8 Q 6(#p)36 G(rints "<)
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(printf "<%2s>", "long";)160 262.8 Q 6(#p)18 G
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(is ne)5.065 F -.05(ga)-.15 G(ti).05 E -.15(ve)-.25 G 5.066(,i).15 G
5.066(th)-5.066 G 2.566(as the same ef)-5.066 F 2.566(fect as the)-.25 F
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(printf \010<%g>\010, 1;)160 495.6 Q 6(#p)48 G(rints "<1>")-6 E
(printf \010<%.10g>\010, 1;)160 507.6 Q 6(#p)30 G(rints "<1>")-6 E
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(printf \010<%.5g>\010, 100.01; # prints "<100.01>")160 555.6 Q
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Q F1(printf \010<%.6d>\010, 1;)160 615.6 Q 6(#p)36 G(rints "<000001>")-6
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699.6 Q 6(#p)36 G(rints "<000001>")-6 E(printf \010<%#.6x>\010, 1;)160
711.6 Q 6(#p)30 G(rints "<0x000001>")-6 E
(printf \010<%\25510.6x>\010, 1;)160 723.6 Q 6(#p)18 G(rints "<000001)-6
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-.15(Fo)148 400.8 S 2.962(rn).15 G .462(umeric con)-2.962 F -.15(ve)-.4
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(rsions, you can specify the size to interpret the number as using).15 F
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(my $s = "The black cat climbed the green tree";)152 441.6 Q(my $color)
152 453.6 Q 6(=s)12 G(ubstr $s, 4, 5;)-6 E 6(#b)36 G(lack)-6 E
(my $middle = substr $s, 4, \25511;)152 465.6 Q 6(#b)24 G
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(ubstr $s, \2554, 2;)-6 E 6(#t)30 G(r)-6 E F0 -1.1(Yo)128 519.6 S 3.47
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2.587(,t)C .086
(he string will shrink, and if you assign something longer than)-2.587 F
F2(LENGTH)128 543.6 Q F0 2.529(,t)C .029(he string will gro)-2.529 F
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(To k)5.029 H .03(eep the string the same length, you may need to).7 F
(pad or chop your v)128 555.6 Q(alue using)-.25 E F1(sprintf)2.5 E F0(.)
A(If)128 573.6 Q F2(OFFSET)3.394 E F0(and)3.394 E F2(LENGTH)3.394 E F0
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(my $oops = substr $name, 7;)152 663.6 Q 6(#r)36 G
(eturns undef, with warning)-6 E(substr\($name, 7\) = \010gap\010;)152
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(ow "The black cat jumped from the green tree")-6 E F0 .804
(Note that the lv)128 126 R .804(alue returned by the three-ar)-.25 F
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(substr\(\))3.304 E F0 .805(acts as a 'magic b)3.305 F .805
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F1($x = \0101234\010;)152 156 Q(for \(substr\($x,1,2\)\) {)152 168 Q
($_ = \010a\010;)176 180 Q(print $x,"\\n";)18 E 6(#p)24 G(rints 1a4)-6 E
($_ = \010xyz\010; print $x,"\\n";)176 192 Q 6(#p)24 G(rints 1xyz4)-6 E
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(Prior to Perl v)128 246 Q(ersion 5.9.1, the result of using an lv)-.15
E(alue multiple times w)-.25 E(as unspeci\214ed.)-.1 E(symlink)108 262.8
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(On systems that don')128 286.8 Q 2.5(ts)-.18 G
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($symlink_exists = eval { symlink\("",""\); 1 };)152 304.8 Q F0(syscall)
108 321.6 Q F3(NUMBER)2.5 E F0(,)A F3(LIST)2.5 E F0 1.984(Calls the sys\
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5.007 F 2.506(xception. The)-.15 F(ar)2.506 E .006
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1.111(If not, the pointer to the)6.111 F 1.792(string v)128 369.6 R
1.792(alue is passed.)-.25 F -1.1(Yo)6.792 G 4.291(ua)1.1 G 1.791
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(recei)128 381.6 Q .732 -.15(ve a)-.25 H .732 -.15(ny r).15 H .433
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128 531.6 Q F1<ad31>3.235 E F0 .735(and sets)3.235 F F1($!)3.235 E F0
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3.603(tr)-3.603 G 1.104(eturns the \214le number of the read end of the)
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F 1.144(ay to retrie)-.1 F 1.444 -.15(ve t)-.25 H 1.144
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1.144(an a)-3.644 F -.2(vo)-.2 G 1.144(id this).2 F(problem by using)128
597.6 Q F1(pipe)2.5 E F0(instead.)2.5 E(sysopen)108 614.4 Q F3
(FILEHANDLE)2.5 E F0(,FILEN)A(AME,MODE)-.35 E(sysopen)108 626.4 Q F3
(FILEHANDLE)2.5 E F0(,FILEN)A(AME,MODE,PERMS)-.35 E 2.49
(Opens the \214le whose \214lename is gi)128 638.4 R -.15(ve)-.25 G
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(f)-7.491 E F3(FILEHANDLE)128 650.4 Q F0 .289(is an e)2.789 F .289
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(be suitably auto)128 662.4 R(vi)-.15 E .966
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(,1m)-.65 G 1.618(eans write-only)-4.118 F 4.118(,a)-.65 G 1.618
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(If the \214le named by)128 156 R F3(FILEN)3.162 E(AME)-.315 E F0 .662
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3.126 F .625(alue of)-.25 F F3(PERMS)3.125 E F0 .625
(speci\214es the permissions of the ne)3.125 F .625(wly created)-.25 F
5.555(\214le. If)128 180 R 3.056(you omit the)5.556 F F3(PERMS)5.556 E
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3.056(erl uses the octal v)-5.556 F(alue)-.25 E F1(0666)5.556 E F0 8.056
(.T)C(hese)-8.056 E(permission v)128 192 Q
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2.5(sc)-.55 G(urrent)-2.5 E F1(umask)2.5 E F0(.)A 2.08(In man)128 210 R
4.58(ys)-.15 G 2.08(ystems the)-4.58 F F1(O_EXCL)4.58 E F0 2.08
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/F4 10/Times-Bold@0 SF(not)4.58 E F0 1.422(locking: e)128 222 R(xclusi)
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(ness means here that if the \214le already e).15 F(xists,)-.15 E F2
(sysopen\(\))3.922 E F0 -.1(fa)3.922 G(ils.).1 E F1(O_EXCL)6.422 E F0
1.423(may not)3.923 F -.1(wo)128 234 S 1.923(rk on netw).1 F 1.923
(ork \214lesystems, and has no ef)-.1 F 1.923(fect unless the)-.25 F F1
(O_CREAT)4.422 E F0 1.922(\215ag is set as well.)4.422 F(Setting)6.922 E
F1(O_CREAT|O_EXCL)128 246 Q F0(pre)3.373 E -.15(ve)-.25 G .874
(nts the \214le from being opened if it is a symbolic link.).15 F .874
(It does not protect)5.874 F(ag)128 258 Q
(ainst symbolic links in the \214le')-.05 E 2.5(sp)-.55 G(ath.)-2.5 E
.705(Sometimes you may w)128 276 R .705(ant to truncate an already-e)-.1
F .705(xisting \214le.)-.15 F .704(This can be done using the)5.705 F F1
(O_TRUNC)3.204 E F0 2.5(\215ag. The)128 288 R(beha)2.5 E(vior of)-.2 E
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E -1.1(Yo)128 306 S 3.648(us)1.1 G 1.148(hould seldom if e)-3.648 F -.15
(ve)-.25 G 3.648(ru).15 G(se)-3.648 E F1(0644)3.648 E F0 1.148(as ar)
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1.149(he user')-3.649 F(s)-.55 E .704(option to ha)128 318 R 1.004 -.15
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(mask. Better).15 F .703(to omit it.)3.203 F .703(See the)5.703 F F2
(perlfunc)3.203 E F0 .703(\(1\) entry on)1.666 F F1(umask)3.203 E F0
(for)3.203 E(more on this.)128 330 Q .568(Note that)128 348 R F1
(sysopen)3.068 E F0 .568(depends on the)3.068 F F2(fdopen\(\))3.068 E F0
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3.068(yU)-.15 G .568(nix systems,)-3.068 F F2(fdopen\(\))3.068 E F0(is)
3.068 E(kno)128 360 Q 2.26(wn to f)-.25 F 2.26
(ail when \214le descriptors e)-.1 F 2.26(xceed a certain v)-.15 F 2.26
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(POSIX::open\(\))128 384 Q F0(function.)2.5 E
(See perlopentut for a kinder)128 402 Q 2.5(,g)-.4 G(entler e)-2.5 E
(xplanation of opening \214les.)-.15 E(sysread)108 418.8 Q F3
(FILEHANDLE)2.5 E F0(,SCALAR,LENGTH,OFFSET)A(sysread)108 430.8 Q F3
(FILEHANDLE)2.5 E F0(,SCALAR,LENGTH)A .204(Attempts to read)128 442.8 R
F3(LENGTH)2.704 E F0 .204(bytes of data into v)2.704 F(ariable)-.25 E F3
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E F0 2.703(,u)C(sing)-2.703 E(the)128 454.8 Q F2 -.37(re)2.581 G(ad).37
E F0 2.581(\(2\). It)1.666 F .082(bypasses b)2.581 F(uf)-.2 E(fered)-.25
E F3(IO)2.582 E F0 2.582(,s)C 2.582(om)-2.582 G .082
(ixing this with other kinds of reads,)-2.582 F F1(print)2.582 E F0(,)A
F1(write)2.582 E F0(,)A F1(seek)2.582 E F0(,)A F1(tell)128 466.8 Q F0
2.69(,o)C(r)-2.69 E F1(eof)2.69 E F0 .189
(can cause confusion because the perlio or stdio layers usually b)2.69 F
(uf)-.2 E .189(fers data.)-.25 F .189(Returns the)5.189 F .595
(number of bytes actually read,)128 478.8 R F1(0)3.095 E F0 .595
(at end of \214le, or undef if there w)3.095 F .595
(as an error \(in the latter case)-.1 F F1($!)3.095 E F0(is)3.095 E .923
(also set\).)128 490.8 R F3(SCALAR)5.923 E F0 .923(will be gro)3.423 F
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of the)-.25 F(scalar after the read.)128 502.8 Q(An)128 520.8 Q F3
(OFFSET)4.882 E F0 2.383(may be speci\214ed to place the read data at s\
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(ginning. A)-.15 F(ne)3.057 E -.05(ga)-.15 G(ti).05 E -.15(ve)-.25 G F3
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(There is no)128 574.8 R F2(syseof\(\))3.917 E F0 1.417
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(vice \214les \(lik)-.25 F 3.916(et)-.1 G(tys\))-3.916 E(an)128 586.8 Q
(yw)-.15 E(ay)-.1 E 5(.U)-.65 G(se)-5 E F2(sysr)2.5 E(ead\(\))-.37 E F0
(and check for a return v)2.5 E(alue for 0 to decide whether you')-.25 E
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604.8 R 1.11(ed as)-.1 F F1(:utf8)3.61 E F0 1.11
(Unicode characters are read instead of bytes)3.61 F(\(the)128 616.8 Q
F3(LENGTH)6.735 E F0(,)A F3(OFFSET)6.735 E F0 6.735(,a)C 4.235
(nd the return v)-6.735 F 4.235(alue of)-.25 F F2(sysr)6.735 E(ead\(\))
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(may return huge lists when used on lar)2.768 F .268(ge objects, lik)
-.18 F(e)-.1 E F1(DBM)128 198 Q F0 2.5(\214les. Y)2.5 F
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2.5 E -.15(ve)-.15 G 2.5(rs).15 G 2.5(uch. Example:)-2.5 F F2 6(#p)152
216 S(rint out history file offsets)-6 E(use NDBM_File;)152 228 Q
(tie\(%HIST, \010NDBM_File\010, \010/usr/lib/news/history\010, 1, 0\);)
152 240 Q(while \(\($key,$val\) = each %HIST\) {)152 252 Q
(print $key, \010 = \010, unpack\(\010L\010,$val\), "\\n";)176 264 Q(})
152 276 Q(untie\(%HIST\);)152 288 Q F0 2.5(Ac)128 306 S
(lass implementing a hash should ha)-2.5 E .3 -.15(ve t)-.2 H(he follo)
.15 E(wing methods:)-.25 E F2(TIEHASH classname, LIST)152 324 Q
(FETCH this, key)152 336 Q(STORE this, key, value)152 348 Q
(DELETE this, key)152 360 Q(CLEAR this)152 372 Q(EXISTS this, key)152
384 Q(FIRSTKEY this)152 396 Q(NEXTKEY this, lastkey)152 408 Q
(SCALAR this)152 420 Q(DESTROY this)152 432 Q(UNTIE this)152 444 Q F0
2.5(Ac)128 462 S(lass implementing an ordinary array should ha)-2.5 E .3
-.15(ve t)-.2 H(he follo).15 E(wing methods:)-.25 E F2
(TIEARRAY classname, LIST)152 480 Q(FETCH this, key)152 492 Q
(STORE this, key, value)152 504 Q(FETCHSIZE this)152 516 Q
(STORESIZE this, count)152 528 Q(CLEAR this)152 540 Q(PUSH this, LIST)
152 552 Q(POP this)152 564 Q(SHIFT this)152 576 Q(UNSHIFT this, LIST)152
588 Q(SPLICE this, offset, length, LIST)152 600 Q(EXTEND this, count)152
612 Q(DESTROY this)152 624 Q(UNTIE this)152 636 Q F0 2.5(Ac)128 654 S
(lass implementing a \214lehandle should ha)-2.5 E .3 -.15(ve t)-.2 H
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152 96 Q(READLINE this)152 108 Q(GETC this)152 120 Q
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180 Q(FILENO this)152 192 Q(SEEK this, position, whence)152 204 Q
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300 Q(FETCH this,)152 312 Q(STORE this, value)152 324 Q(DESTROY this)152
336 Q(UNTIE this)152 348 Q F0 .326(Not all methods indicated abo)128 366
R .626 -.15(ve n)-.15 H .326(eed be implemented.).15 F .326
(See perltie, T)5.326 F .325(ie::Hash, T)-.35 F(ie::Array)-.35 E 2.825
(,T)-.65 G(ie::Scalar)-3.175 E(,)-.4 E(and T)128 378 Q(ie::Handle.)-.35
E(Unlik)128 396 Q(e)-.1 E F1(dbmopen)2.756 E F0 2.756(,t)C(he)-2.756 E
F1(tie)2.756 E F0 .256(function will not)2.756 F F1(use)2.757 E F0(or)
2.757 E F1(require)2.757 E F0 2.757(am)2.757 G .257
(odule for you; you need to do that)-2.757 F -.15(ex)128 408 S
(plicitly yourself.).15 E(See DB_File or the)5 E/F2 10/Times-Italic@0 SF
(Con\214g)2.5 E F0(module for interesting)2.5 E F1(tie)2.5 E F0
(implementations.)2.5 E -.15(Fo)128 426 S 2.5(rf).15 G
(urther details see perltie, `)-2.5 E(`tied)-.74 E/F3 9/Times-Roman@0 SF
-1.215(VA)2.5 G(RIABLE)1.215 E F0 -.74('')C(.).74 E(tied)108 442.8 Q F3
-1.215(VA)2.5 G(RIABLE)1.215 E F0 .86
(Returns a reference to the object underlying)128 454.8 R F3 -1.215(VA)
3.36 G(RIABLE)1.215 E F0 .86(\(the same v)3.36 F .86(alue that w)-.25 F
.86(as originally returned)-.1 F .304(by the)128 466.8 R F1(tie)2.804 E
F0 .304(call that bound the v)2.804 F .305(ariable to a package.\))-.25
F .305(Returns the unde\214ned v)5.305 F .305(alue if)-.25 F F3 -1.215
(VA)2.805 G(RIABLE)1.215 E F0(isn')2.805 E(t)-.18 E(tied to a package.)
128 478.8 Q(time)108 495.6 Q 1.165
(Returns the number of non-leap seconds since whate)128 507.6 R -.15(ve)
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-3.665 F 1.953(suitable for feeding to)128 519.6 R F1(gmtime)4.453 E F0
(and)4.453 E F1(localtime)4.453 E F0 4.454(.O)C 4.454(nm)-4.454 G 1.954
(ost systems the epoch is 00:00:00)-4.454 F F3(UTC)4.454 E F0(,)A .676
(January 1, 1970; a prominent e)128 531.6 R .676(xception being Mac)-.15
F F3(OS)3.176 E F0 .676(Classic which uses 00:00:00, January 1, 1904)
3.176 F(in the current local time zone for its epoch.)128 543.6 Q -.15
(Fo)128 561.6 S 3.169(rm).15 G .669
(easuring time in better granularity than one second, use the T)-3.169 F
.67(ime::HiRes module from Perl 5.8)-.35 F(onw)128 573.6 Q 1.397
(ards \(or from)-.1 F F3(CP)3.897 E(AN)-.828 E F0 1.397
(before then\), or)3.897 F 3.897(,i)-.4 G 3.897(fy)-3.897 G 1.397(ou ha)
-3.897 F -.15(ve)-.2 G F2 -.1(ge)4.047 G(ttimeofday).1 E F0 1.397
(\(2\), you may be able to use the)1.666 F F1(syscall)128 585.6 Q F0
(interf)2.5 E(ace of Perl.)-.1 E(See perlf)5 E(aq8 for details.)-.1 E
-.15(Fo)128 603.6 S 3.316(rd).15 G .816
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(or a comprehensi)-5.967 F 1.117 -.15(ve d)-.25 H(ate).15 E
(and time representation look at the DateT)128 615.6 Q(ime module.)-.35
E(times)108 632.4 Q .214(Returns a four)128 644.4 R .214
(-element list gi)-.2 F .213
(ving the user and system times in seconds for this process and an)-.25
F 2.713(ye)-.15 G(xited)-2.863 E(children of this process.)128 656.4 Q
F1(\($user,$system,$cuser,$csystem\) = times;)152 674.4 Q F0
(In scalar conte)128 692.4 Q(xt,)-.15 E F1(times)2.5 E F0(returns)2.5 E
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2.5(eO)-.1 G(perators')-2.5 E 2.5('i)-.74 G 2.5(np)-2.5 G(erlop.)-2.5 E
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A(truncate)108 112.8 Q F2(EXPR)2.5 E F0(,LENGTH)A -.35(Tr)128 124.8 S
1.43(uncates the \214le opened on).35 F F2(FILEHANDLE)3.93 E F0 3.93(,o)
C 3.93(rn)-3.93 G 1.43(amed by)-3.93 F F2(EXPR)3.931 E F0 3.931(,t)C
3.931(ot)-3.931 G 1.431(he speci\214ed length.)-3.931 F 1.431(Raises an)
6.431 F -.15(ex)128 136.8 S(ception if truncate isn').15 E 2.5(ti)-.18 G
(mplemented on your system.)-2.5 E(Returns true if successful,)5 E F1
(undef)2.5 E F0(on error)2.5 E(.)-.55 E(The beha)128 154.8 Q
(vior is unde\214ned if)-.2 E F2(LENGTH)2.5 E F0
(is greater than the length of the \214le.)2.5 E .542
(The position in the \214le of)128 172.8 R F2(FILEHANDLE)3.041 E F0 .541
(is left unchanged.)3.041 F -1.1(Yo)5.541 G 3.041(um)1.1 G .541(ay w)
-3.041 F .541(ant to call seek before writing)-.1 F(to the \214le.)128
184.8 Q(uc)108 201.6 Q F2(EXPR)2.5 E F0(uc)108 213.6 Q .572
(Returns an uppercased v)128 213.6 R .572(ersion of)-.15 F F2(EXPR)3.072
E F0 5.572(.T)C .572(his is the internal function implementing the)
-5.572 F F1(\\U)3.073 E F0 .573(escape in)3.073 F .438
(double-quoted strings.)128 225.6 R .438
(It does not attempt to do titlecase mapping on initial letters.)5.438 F
.438(See `)5.438 F(`uc\214rst')-.74 E 2.938('f)-.74 G(or)-2.938 E(that.)
128 237.6 Q(If)128 255.6 Q F2(EXPR)2.5 E F0(is omitted, uses)2.5 E F1
($_)2.5 E F0(.)A(This function beha)128 273.6 Q -.15(ve)-.2 G 2.5(st).15
G(he same w)-2.5 E(ay under v)-.1 E
(arious pragma, such as in a locale, as `)-.25 E(`lc')-.74 E 2.5('d)-.74
G(oes.)-2.5 E(uc\214rst)108 290.4 Q F2(EXPR)2.5 E F0(uc\214rst)108 302.4
Q 1.45(Returns the v)128 314.4 R 1.45(alue of)-.25 F F2(EXPR)3.95 E F0
1.45(with the \214rst character in uppercase \(titlecase in Unicode\).)
3.95 F 1.451(This is the)6.451 F(internal function implementing the)128
326.4 Q F1(\\u)2.5 E F0(escape in double-quoted strings.)2.5 E(If)128
344.4 Q F2(EXPR)2.5 E F0(is omitted, uses)2.5 E F1($_)2.5 E F0(.)A
(This function beha)128 362.4 Q -.15(ve)-.2 G 2.5(st).15 G(he same w)
-2.5 E(ay under v)-.1 E(arious pragma, such as in a locale, as `)-.25 E
(`lc')-.74 E 2.5('d)-.74 G(oes.)-2.5 E(umask)108 379.2 Q F2(EXPR)2.5 E
F0(umask)108 391.2 Q 1.039(Sets the umask for the process to)128 403.2 R
F2(EXPR)3.538 E F0 1.038(and returns the pre)3.538 F 1.038(vious v)-.25
F 3.538(alue. If)-.25 F F2(EXPR)3.538 E F0 1.038(is omitted, merely)
3.538 F(returns the current umask.)128 415.2 Q .027(The Unix permission)
128 433.2 R F1<72777872ad78adadad>2.527 E F0 .028
(is represented as three sets of three bits, or three octal digits:)
2.527 F F1(0750)2.528 E F0 2.352
(\(the leading 0 indicates octal and isn')128 445.2 R 4.852(to)-.18 G
2.352(ne of the digits\).)-4.852 F(The)7.352 E F1(umask)4.852 E F0 -.25
(va)4.852 G 2.351(lue is such a number).25 F 2.305
(representing disabled permissions bits.)128 457.2 R 2.306
(The permission \(or `)7.306 F(`mode')-.74 E 2.306('\) v)-.74 F 2.306
(alues you pass)-.25 F F1(mkdir)4.806 E F0(or)4.806 E F1(sysopen)128
469.2 Q F0 .3(are modi\214ed by your umask, so e)2.8 F -.15(ve)-.25 G
2.8(ni).15 G 2.8(fy)-2.8 G .3(ou tell)-2.8 F F1(sysopen)2.8 E F0 .3
(to create a \214le with permissions)2.8 F F1(0777)128 481.2 Q F0 3.204
(,i)C 3.204(fy)-3.204 G .704(our umask is)-3.204 F F1(0022)3.204 E F0
3.205(,t)C .705
(hen the \214le will actually be created with permissions)-3.205 F F1
(0755)3.205 E F0 5.705(.I)C 3.205(fy)-5.705 G(our)-3.205 E F1(umask)128
493.2 Q F0(were)3.439 E F1(0027)3.439 E F0 .939(\(group can')3.439 F
3.439(tw)-.18 G .939(rite; others can')-3.439 F 3.439(tr)-.18 G .938
(ead, write, or e)-3.439 F -.15(xe)-.15 G .938(cute\), then passing).15
F F1(sysopen)3.438 E(0666)128 505.2 Q F0 -.1(wo)2.5 G
(uld create a \214le with mode).1 E F1(0640)2.5 E F0(\(because)2.5 E F1
(0666 &~ 027)2.5 E F0(is)2.5 E F1(0640)2.5 E F0(\).)A(Here')128 523.2 Q
2.581(ss)-.55 G .081(ome advice: supply a creation mode of)-2.581 F F1
(0666)2.582 E F0 .082(for re)2.582 F .082(gular \214les \(in)-.15 F F1
(sysopen)2.582 E F0 2.582(\)a)C .082(nd one of)-2.582 F F1(0777)2.582 E
F0 .676(for directories \(in)128 535.2 R F1(mkdir)3.176 E F0 3.176(\)a)C
.676(nd e)-3.176 F -.15(xe)-.15 G .676(cutable \214les.).15 F .676
(This gi)5.676 F -.15(ve)-.25 G 3.176(su).15 G .675
(sers the freedom of choice: if the)-3.176 F 3.175(yw)-.15 G(ant)-3.275
E 1.404(protected \214les, the)128 547.2 R 3.904(ym)-.15 G 1.404
(ight choose process umasks of)-3.904 F F1(022)3.904 E F0(,)A F1(027)
3.904 E F0 3.904(,o)C 3.905(re)-3.904 G -.15(ve)-4.155 G 3.905(nt).15 G
1.405(he particularly antisocial)-3.905 F 1.996(mask of)128 559.2 R F1
(077)4.496 E F0 6.996(.P)C 1.996(rograms should rarely if e)-6.996 F
-.15(ve)-.25 G 4.496(rm).15 G(ak)-4.496 E 4.496(ep)-.1 G(olic)-4.496 E
4.496(yd)-.15 G 1.995(ecisions better left to the user)-4.496 F 6.995
(.T)-.55 G(he)-6.995 E -.15(ex)128 571.2 S 1.265
(ception to this is when writing \214les that should be k).15 F 1.266
(ept pri)-.1 F -.25(va)-.25 G 1.266(te: mail \214les, web bro).25 F
1.266(wser cookies,)-.25 F/F3 10/Times-Italic@0 SF(.rhosts)128 583.2 Q
F0(\214les, and so on.)2.5 E(If)128 601.2 Q F3(umask)2.955 E F0 .454(\(\
2\) is not implemented on your system and you are trying to restrict ac\
cess for)1.666 F F3(your)2.954 E(self)-.1 E F0(\(i.e.,)2.954 E F1 .012
(\(EXPR & 0700\) > 0)128 613.2 R F0 .012(\), raises an e)B 2.512
(xception. If)-.15 F F3(umask)2.512 E F0 .012
(\(2\) is not implemented and you are not trying)1.666 F
(to restrict access for yourself, returns)128 625.2 Q F1(undef)2.5 E F0
(.)A .516(Remember that a umask is a number)128 643.2 R 3.016(,u)-.4 G
.516(sually gi)-3.016 F -.15(ve)-.25 G 3.016(ni).15 G 3.016(no)-3.016 G
.516(ctal; it is)-3.016 F F3(not)3.016 E F0 3.016(as)3.016 G .516
(tring of octal digits.)-3.016 F .516(See also)5.516 F -.74(``)128 655.2
S(oct').74 E(', if all you ha)-.74 E .3 -.15(ve i)-.2 H 2.5(sas).15 G
(tring.)-2.5 E(undef)108 672 Q F2(EXPR)2.5 E F0(undef)108 684 Q .142
(Unde\214nes the v)128 696 R .143(alue of)-.25 F F2(EXPR)2.643 E F0
2.643(,w)C .143(hich must be an lv)-2.643 F 2.643(alue. Use)-.25 F .143
(only on a scalar v)2.643 F .143(alue, an array \(using)-.25 F F1(@)
2.643 E F0(\),)A 3.646(ah)128 708 S 1.146(ash \(using)-3.646 F F1(%)
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(\), or a type)B 1.145(glob \(using)-.15 F F1(*)3.645 E F0 3.645
(\). Saying)B F1 1.145(undef $hash{$key})3.645 F F0 1.119
(will probably not do what you e)128 720 R 1.119
(xpect on most prede\214ned v)-.15 F 1.119(ariables or)-.25 F F2(DBM)
3.619 E F0 1.12(list v)3.62 F 1.12(alues, so don')-.25 F 3.62(td)-.18 G
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(unde\214ned, b)128 96 R .677(ut you still get an unde\214ned v)-.2 F
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(assign to a v)128 108 Q(ariable, or pass as a parameter)-.25 E 5(.E)
-.55 G(xamples:)-5 E/F2 10/Courier@0 SF(undef $foo;)152 126 Q
(undef $bar{\010blurfl\010};)152 138 Q 6(#C)36 G
(ompare to: delete $bar{\010blurfl\010};)-6 E(undef @ary;)152 150 Q
(undef %hash;)152 162 Q(undef &mysub;)152 174 Q(undef *xyz;)152 186 Q 6
(#d)42 G(estroys $xyz, @xyz, %xyz, &xyz, etc.)-6 E
(return \(wantarray ? \(undef, $errmsg\) : undef\) if $they_blew_it;)152
198 Q(select undef, undef, undef, 0.25;)152 210 Q
(\($a, $b, undef, $c\) = &foo;)152 222 Q 6(#I)42 G
(gnore third value returned)-6 E F0(Note that this is a unary operator)
128 240 Q 2.5(,n)-.4 G(ot a list operator)-2.5 E(.)-.55 E(unlink)108
256.8 Q F1(LIST)2.5 E F0(unlink)108 268.8 Q .829(Deletes a list of \214\
les. On success, it returns the number of \214les it successfully delet\
ed. On f)128 280.8 R .829(ailure, it)-.1 F(returns f)128 292.8 Q
(alse and sets)-.1 E F2($!)2.5 E F0(\(errno\):)5 E F2
(my $unlinked = unlink \010a\010, \010b\010, \010c\010;)152 310.8 Q
(unlink @goners;)152 322.8 Q(unlink glob "*.bak";)152 334.8 Q F0 .547
(On error)128 352.8 R(,)-.4 E F2(unlink)3.047 E F0 .548
(will not tell you which \214les it could not remo)3.048 F -.15(ve)-.15
G 5.548(.I).15 G 3.048(fy)-5.548 G .548(ou w)-3.048 F .548(ant to kno)
-.1 F 3.048(ww)-.25 G .548(hich \214les)-3.048 F(you could not remo)128
364.8 Q -.15(ve)-.15 G 2.5(,t).15 G(ry them one at a time:)-2.5 E F2
(foreach my $file \( @goners \) {)158 382.8 Q
(unlink $file or warn "Could not unlink $file: $!";)182 394.8 Q(})158
406.8 Q F0(Note:)128 424.8 Q F2(unlink)4.362 E F0 1.862(will not attemp\
t to delete directories unless you are superuser and the)4.362 F/F3 10
/Times-Bold@0 SF<ad55>4.362 E F0 1.861(\215ag is)4.361 F 1.463
(supplied to Perl. Ev)128 436.8 R 1.463
(en if these conditions are met, be w)-.15 F 1.463
(arned that unlinking a directory can in\215ict)-.1 F .23
(damage on your \214lesystem.)128 448.8 R(Finally)5.23 E 2.729(,u)-.65 G
(sing)-2.729 E F2(unlink)2.729 E F0 .229
(on directories is not supported on man)2.729 F 2.729(yo)-.15 G
(perating)-2.729 E 2.5(systems. Use)128 460.8 R F2(rmdir)2.5 E F0
(instead.)2.5 E(If)128 478.8 Q F1(LIST)2.5 E F0(is omitted,)2.5 E F2
(unlink)2.5 E F0(uses)2.5 E F2($_)2.5 E F0(.)A(unpack)108 495.6 Q F1
(TEMPLA)2.5 E(TE)-.999 E F0(,EXPR)A(unpack)108 507.6 Q F1(TEMPLA)2.5 E
(TE)-.999 E F2(unpack)128 519.6 Q F0 .37(does the re)2.87 F -.15(ve)-.25
G .37(rse of).15 F F2(pack)2.87 E F0 2.87(:i)C 2.87(tt)-2.87 G(ak)-2.87
E .37(es a string and e)-.1 F .37(xpands it out into a list of v)-.15 F
2.87(alues. \(In)-.25 F(scalar)2.87 E(conte)128 531.6 Q
(xt, it returns merely the \214rst v)-.15 E(alue produced.\))-.25 E(If)
128 549.6 Q F1(EXPR)2.5 E F0(is omitted, unpacks the)2.5 E F2($_)2.5 E
F0 2.5(string. See)2.5 F
(perlpacktut for an introduction to this function.)2.5 E .073
(The string is brok)128 567.6 R .073(en into chunks described by the)-.1
F F1(TEMPLA)2.573 E(TE)-.999 E F0 5.072(.E)C .072(ach chunk is con)
-5.072 F -.15(ve)-.4 G .072(rted separately to a).15 F -.25(va)128 579.6
S 3.783(lue. T).25 F(ypically)-.8 E 3.783(,e)-.65 G 1.284
(ither the string is a result of)-3.783 F F2(pack)3.784 E F0 3.784(,o)C
3.784(rt)-3.784 G 1.284(he characters of the string represent a C)-3.784
F(structure of some kind.)128 591.6 Q(The)128 609.6 Q F1(TEMPLA)2.5 E
(TE)-.999 E F0(has the same format as in the)2.5 E F2(pack)2.5 E F0 2.5
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424.8 Q F0(,)A F2(0x20)4.63 E F0(,)A F2(0x40)4.63 E F0(,)A F2(0x80)4.63
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(vec\($image, $max_x * $x + $y, 8\) = 3;)152 484.8 Q F0 .81
(If the selected element is outside the string, the v)128 502.8 R .809
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2.516(,a)C .017(nd it operates on the internal byte string, not the con\
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(my $foo = \010\010;)152 670.8 Q 6(vec\($foo, 0,)152 682.8 R
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(r\010 is "\\x72")-6 E(vec\($foo, 45,)152 168 Q(2\) = 3;)12 E 6<2308>36
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(1\) = 1;)12 E 6<2308>36 G 6(PerlPerlPer\010 .)-6 F("\\x2c")6 E
(vec\($foo, 94,)152 192 Q(1\) = 1;)12 E 6<2308>36 G(PerlPerlPerl\010)-6
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(ransform a bit v).8 E(ector into a string or list of 0')-.15 E 2.5(sa)
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($bits = unpack\("b*", $vector\);)152 240 Q
(@bits = split\(//, unpack\("b*", $vector\)\);)152 252 Q F0(If you kno)
128 270 Q 2.5(wt)-.25 G(he e)-2.5 E
(xact length in bits, it can be used in place of the)-.15 E F1(*)2.5 E
F0(.)A(Here is an e)128 288 Q(xample to illustrate ho)-.15 E 2.5(wt)-.25
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(#!/usr/bin/perl \255wl)152 306 Q(print <<\010EOT\010;)152 330 Q 54
(0123)356 342 S(unpack\("V",$_\) 01234567890123456789012345678901)266
354 Q<adadadadadadadadadadadadadadadadadadadadadadadadadadadadadadadadad
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366 Q(EOT)152 378 Q(for $w \(0..3\) {)152 402 Q($width = 2**$w;)176 414
Q(for \($shift=0; $shift < $width; ++$shift\) {)176 426 Q
(for \($off=0; $off < 32/$width; ++$off\) {)200 438 Q
($str = pack\("B*", "0"x32\);)224 450 Q($bits = \(1<<$shift\);)224 462 Q
(vec\($str, $off, $width\) = $bits;)224 474 Q
($res = unpack\("b*",$str\);)224 486 Q($val = unpack\("V", $str\);)224
498 Q(write;)224 510 Q(})200 522 Q(})176 534 Q(})152 546 Q
(format STDOUT =)152 570 Q
(vec\($_,@#,@#\) = @<< == @######### @>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>)
152 582 Q($off, $width, $bits, $val, $res)152 594 Q(.)152 606 Q 1.666
(__)152 618 S -4.334(END_ _)-1.666 F F0(Re)128 636 Q -.05(ga)-.15 G .235
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108 Q(vec\($_, 0, 1\) = 1)152 120 Q 54(== 1)18 F
(10000000000000000000000000000000)6 E(vec\($_, 1, 1\) = 1)152 132 Q 54
(== 2)18 F(01000000000000000000000000000000)6 E(vec\($_, 2, 1\) = 1)152
144 Q 54(== 4)18 F(00100000000000000000000000000000)6 E
(vec\($_, 3, 1\) = 1)152 156 Q 54(== 8)18 F
(00010000000000000000000000000000)6 E(vec\($_, 4, 1\) = 1)152 168 Q 48
(== 16)18 F(00001000000000000000000000000000)6 E(vec\($_, 5, 1\) = 1)152
180 Q 48(== 32)18 F(00000100000000000000000000000000)6 E
(vec\($_, 6, 1\) = 1)152 192 Q 48(== 64)18 F
(00000010000000000000000000000000)6 E(vec\($_, 7, 1\) = 1)152 204 Q 42
(== 128)18 F(00000001000000000000000000000000)6 E(vec\($_, 8, 1\) = 1)
152 216 Q 42(== 256)18 F(00000000100000000000000000000000)6 E
(vec\($_, 9, 1\) = 1)152 228 Q 42(== 512)18 F
(00000000010000000000000000000000)6 E(vec\($_,10, 1\) = 1)152 240 Q 36
(== 1024)18 F(00000000001000000000000000000000)6 E(vec\($_,11, 1\) = 1)
152 252 Q 36(== 2048)18 F(00000000000100000000000000000000)6 E
(vec\($_,12, 1\) = 1)152 264 Q 36(== 4096)18 F
(00000000000010000000000000000000)6 E(vec\($_,13, 1\) = 1)152 276 Q 36
(== 8192)18 F(00000000000001000000000000000000)6 E(vec\($_,14, 1\) = 1)
152 288 Q 30(== 16384)18 F(00000000000000100000000000000000)6 E
(vec\($_,15, 1\) = 1)152 300 Q 30(== 32768)18 F
(00000000000000010000000000000000)6 E(vec\($_,16, 1\) = 1)152 312 Q 30
(== 65536)18 F(00000000000000001000000000000000)6 E(vec\($_,17, 1\) = 1)
152 324 Q 24(== 131072)18 F(00000000000000000100000000000000)6 E
(vec\($_,18, 1\) = 1)152 336 Q 24(== 262144)18 F
(00000000000000000010000000000000)6 E(vec\($_,19, 1\) = 1)152 348 Q 24
(== 524288)18 F(00000000000000000001000000000000)6 E
(vec\($_,20, 1\) = 1)152 360 Q 18(== 1048576)18 F
(00000000000000000000100000000000)6 E(vec\($_,21, 1\) = 1)152 372 Q 18
(== 2097152)18 F(00000000000000000000010000000000)6 E
(vec\($_,22, 1\) = 1)152 384 Q 18(== 4194304)18 F
(00000000000000000000001000000000)6 E(vec\($_,23, 1\) = 1)152 396 Q 18
(== 8388608)18 F(00000000000000000000000100000000)6 E
(vec\($_,24, 1\) = 1)152 408 Q 12(== 16777216)18 F
(00000000000000000000000010000000)6 E(vec\($_,25, 1\) = 1)152 420 Q 12
(== 33554432)18 F(00000000000000000000000001000000)6 E
(vec\($_,26, 1\) = 1)152 432 Q 12(== 67108864)18 F
(00000000000000000000000000100000)6 E(vec\($_,27, 1\) = 1)152 444 Q 6
(== 134217728)18 F(00000000000000000000000000010000)6 E
(vec\($_,28, 1\) = 1)152 456 Q 6(== 268435456)18 F
(00000000000000000000000000001000)6 E(vec\($_,29, 1\) = 1)152 468 Q 6
(== 536870912)18 F(00000000000000000000000000000100)6 E
(vec\($_,30, 1\) = 1)152 480 Q
(== 1073741824 00000000000000000000000000000010)18 E
(vec\($_,31, 1\) = 1)152 492 Q
(== 2147483648 00000000000000000000000000000001)18 E
(vec\($_, 0, 2\) = 1)152 504 Q 54(== 1)18 F
(10000000000000000000000000000000)6 E(vec\($_, 1, 2\) = 1)152 516 Q 54
(== 4)18 F(00100000000000000000000000000000)6 E(vec\($_, 2, 2\) = 1)152
528 Q 48(== 16)18 F(00001000000000000000000000000000)6 E
(vec\($_, 3, 2\) = 1)152 540 Q 48(== 64)18 F
(00000010000000000000000000000000)6 E(vec\($_, 4, 2\) = 1)152 552 Q 42
(== 256)18 F(00000000100000000000000000000000)6 E(vec\($_, 5, 2\) = 1)
152 564 Q 36(== 1024)18 F(00000000001000000000000000000000)6 E
(vec\($_, 6, 2\) = 1)152 576 Q 36(== 4096)18 F
(00000000000010000000000000000000)6 E(vec\($_, 7, 2\) = 1)152 588 Q 30
(== 16384)18 F(00000000000000100000000000000000)6 E(vec\($_, 8, 2\) = 1)
152 600 Q 30(== 65536)18 F(00000000000000001000000000000000)6 E
(vec\($_, 9, 2\) = 1)152 612 Q 24(== 262144)18 F
(00000000000000000010000000000000)6 E(vec\($_,10, 2\) = 1)152 624 Q 18
(== 1048576)18 F(00000000000000000000100000000000)6 E
(vec\($_,11, 2\) = 1)152 636 Q 18(== 4194304)18 F
(00000000000000000000001000000000)6 E(vec\($_,12, 2\) = 1)152 648 Q 12
(== 16777216)18 F(00000000000000000000000010000000)6 E
(vec\($_,13, 2\) = 1)152 660 Q 12(== 67108864)18 F
(00000000000000000000000000100000)6 E(vec\($_,14, 2\) = 1)152 672 Q 6
(== 268435456)18 F(00000000000000000000000000001000)6 E
(vec\($_,15, 2\) = 1)152 684 Q
(== 1073741824 00000000000000000000000000000010)18 E
(vec\($_, 0, 2\) = 2)152 696 Q 54(== 2)18 F
(01000000000000000000000000000000)6 E(vec\($_, 1, 2\) = 2)152 708 Q 54
(== 8)18 F(00010000000000000000000000000000)6 E(vec\($_, 2, 2\) = 2)152
720 Q 48(== 32)18 F(00000100000000000000000000000000)6 E F0
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(vec\($_, 3, 2\) = 2)152 84 Q 42(== 128)18 F
(00000001000000000000000000000000)6 E(vec\($_, 4, 2\) = 2)152 96 Q 42
(== 512)18 F(00000000010000000000000000000000)6 E(vec\($_, 5, 2\) = 2)
152 108 Q 36(== 2048)18 F(00000000000100000000000000000000)6 E
(vec\($_, 6, 2\) = 2)152 120 Q 36(== 8192)18 F
(00000000000001000000000000000000)6 E(vec\($_, 7, 2\) = 2)152 132 Q 30
(== 32768)18 F(00000000000000010000000000000000)6 E(vec\($_, 8, 2\) = 2)
152 144 Q 24(== 131072)18 F(00000000000000000100000000000000)6 E
(vec\($_, 9, 2\) = 2)152 156 Q 24(== 524288)18 F
(00000000000000000001000000000000)6 E(vec\($_,10, 2\) = 2)152 168 Q 18
(== 2097152)18 F(00000000000000000000010000000000)6 E
(vec\($_,11, 2\) = 2)152 180 Q 18(== 8388608)18 F
(00000000000000000000000100000000)6 E(vec\($_,12, 2\) = 2)152 192 Q 12
(== 33554432)18 F(00000000000000000000000001000000)6 E
(vec\($_,13, 2\) = 2)152 204 Q 6(== 134217728)18 F
(00000000000000000000000000010000)6 E(vec\($_,14, 2\) = 2)152 216 Q 6
(== 536870912)18 F(00000000000000000000000000000100)6 E
(vec\($_,15, 2\) = 2)152 228 Q
(== 2147483648 00000000000000000000000000000001)18 E
(vec\($_, 0, 4\) = 1)152 240 Q 54(== 1)18 F
(10000000000000000000000000000000)6 E(vec\($_, 1, 4\) = 1)152 252 Q 48
(== 16)18 F(00001000000000000000000000000000)6 E(vec\($_, 2, 4\) = 1)152
264 Q 42(== 256)18 F(00000000100000000000000000000000)6 E
(vec\($_, 3, 4\) = 1)152 276 Q 36(== 4096)18 F
(00000000000010000000000000000000)6 E(vec\($_, 4, 4\) = 1)152 288 Q 30
(== 65536)18 F(00000000000000001000000000000000)6 E(vec\($_, 5, 4\) = 1)
152 300 Q 18(== 1048576)18 F(00000000000000000000100000000000)6 E
(vec\($_, 6, 4\) = 1)152 312 Q 12(== 16777216)18 F
(00000000000000000000000010000000)6 E(vec\($_, 7, 4\) = 1)152 324 Q 6
(== 268435456)18 F(00000000000000000000000000001000)6 E
(vec\($_, 0, 4\) = 2)152 336 Q 54(== 2)18 F
(01000000000000000000000000000000)6 E(vec\($_, 1, 4\) = 2)152 348 Q 48
(== 32)18 F(00000100000000000000000000000000)6 E(vec\($_, 2, 4\) = 2)152
360 Q 42(== 512)18 F(00000000010000000000000000000000)6 E
(vec\($_, 3, 4\) = 2)152 372 Q 36(== 8192)18 F
(00000000000001000000000000000000)6 E(vec\($_, 4, 4\) = 2)152 384 Q 24
(== 131072)18 F(00000000000000000100000000000000)6 E
(vec\($_, 5, 4\) = 2)152 396 Q 18(== 2097152)18 F
(00000000000000000000010000000000)6 E(vec\($_, 6, 4\) = 2)152 408 Q 12
(== 33554432)18 F(00000000000000000000000001000000)6 E
(vec\($_, 7, 4\) = 2)152 420 Q 6(== 536870912)18 F
(00000000000000000000000000000100)6 E(vec\($_, 0, 4\) = 4)152 432 Q 54
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444 Q 48(== 64)18 F(00000010000000000000000000000000)6 E
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4.727 E F0(,)A F2(chmod)4.727 E F0(,)A F2(chown)4.727 E F0(,)A F2
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194.4 Q F0(,)A F1(msgget)3 E F0(,)A F1(msgrcv)3 E F0(,)A F1(msgsnd)3 E
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(endgrent)128 235.2 Q F0(,)A F1(endhostent)6.75 E F0(,)A F1(endnetent)
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334.8 Q F0(does nothing. It returns true on success, f)2.5 E
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1.666 F 2.735(gument. On)-.18 F(systems that don')128 364.8 Q 2.5(ts)
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381.6 Q F3(LIST)2.5 E F0 1.3
(Changes the permissions of a list of \214les.)128 393.6 R 1.301
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(be a string of octal digits:)2.872 F F1(0644)128 417.6 Q F0 .395
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(is not.)2.895 F .395
(Returns the number of \214les successfully changed.)5.395 F .395
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152 459.6 Q($mode = "0644"; chmod $mode, "foo";)152 471.6 Q 6(#!)36 G
(!! sets mode to)-6 E 6<23ad>398 483.6 S<ad77adadadad72ad54>-6 E
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($mode = 0644;)152 507.6 Q(chmod $mode, "foo";)18 E 6(#t)36 G
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2.953 E(hmod)-.15 E F0 .453
(\(2\), you may pass \214lehandles among the \214les.)1.666 F .453
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567.6 Q(my $perm = \(stat $fh\)[2] & 07777;)152 579.6 Q
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(chmod S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH, @executables;)152 639.6
Q 6(#I)152 651.6 S(dentical to the chmod 0755 of the example above.)-6 E
F0(chomp)108 668.4 Q F3 -1.215(VA)2.5 G(RIABLE)1.215 E F0(chomp\()108
680.4 Q F3(LIST)2.5 E F0(\))2.5 E(chomp)108 692.4 Q .811(This safer v)
128 704.4 R .811(ersion of `)-.15 F(`chop')-.74 E 3.311('r)-.74 G(emo)
-3.311 E -.15(ve)-.15 G 3.311(sa).15 G 1.111 -.15(ny t)-3.311 H .81
(railing string that corresponds to the current v).15 F .81(alue of)-.25
F F1($/)3.31 E F0 2.504(\(also kno)128 716.4 R 2.504(wn as)-.25 F F1
($INPUT_RECORD_SEPARATOR)5.004 E F0 2.504(in the)5.004 F F1(English)
5.005 E F0 5.005(module\). It)5.005 F 2.505(returns the total)5.005 F
.507(number of characters remo)128 728.4 R -.15(ve)-.15 G 3.007(df).15 G
.507(rom all its ar)-3.007 F 3.007(guments. It')-.18 F 3.007(so)-.55 G
.507(ften used to remo)-3.007 F .807 -.15(ve t)-.15 H .507(he ne).15 F
.506(wline from the)-.25 F(perl v5.14.2)72 768 Q 203.17(2011-10-01 9)
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
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(end of an input record when you')128 84 R .255(re w)-.5 F .255
(orried that the \214nal record may be missing its ne)-.1 F 2.755
(wline. When)-.25 F(in)2.755 E 1.062(paragraph mode \()128 96 R/F1 10
/Courier@0 SF 1.062($/ = "")B F0 1.062(\), it remo)B -.15(ve)-.15 G
3.562(sa).15 G 1.062(ll trailing ne)-3.562 F 1.062
(wlines from the string.)-.25 F 1.061(When in slurp mode)6.062 F(\()128
108 Q F1 .566($/ = undef)B F0 3.066(\)o)C 3.066<728c>-3.066 G -.15(xe)
-3.066 G .566(d-length record mode \().15 F F1($/)A F0 .567
(is a reference to an inte)3.067 F .567(ger or the lik)-.15 F .567
(e; see perlv)-.1 F(ar\))-.25 E/F2 10/Times-Italic@0 SF -.15(ch)128 120
S(omp\(\)).15 E F0 -.1(wo)2.5 G(n').1 E 2.5(tr)-.18 G(emo)-2.5 E .3 -.15
(ve a)-.15 H -.15(ny).15 G 2.5(thing. If).15 F/F3 9/Times-Roman@0 SF
-1.215(VA)2.5 G(RIABLE)1.215 E F0(is omitted, it chomps)2.5 E F1($_)2.5
E F0 5(.E)C(xample:)-5 E F1(while \(<>\) {)152 138 Q 6(chomp; #)176 150
R(avoid \\n on last field)6 E(@array = split\(/:/\);)176 162 Q 6(#.)176
174 S(..)-6 E(})152 186 Q F0(If)128 204 Q F3 -1.215(VA)2.5 G(RIABLE)
1.215 E F0(is a hash, it chomps the hash')2.5 E 2.5(sv)-.55 G(alues, b)
-2.75 E(ut not its k)-.2 E -.15(ey)-.1 G(s.).15 E -1.1(Yo)128 222 S 2.5
(uc)1.1 G(an actually chomp an)-2.5 E(ything that')-.15 E 2.5(sa)-.55 G
2.5(nl)-2.5 G -.25(va)-2.5 G(lue, including an assignment:).25 E F1
(chomp\($cwd = \222pwd\222\);)152 240 Q(chomp\($answer = <STDIN>\);)152
252 Q F0(If you chomp a list, each element is chomped, and the total nu\
mber of characters remo)128 270 Q -.15(ve)-.15 G 2.5(di).15 G 2.5(sr)
-2.5 G(eturned.)-2.5 E 1.622
(Note that parentheses are necessary when you')128 288 R 1.621
(re chomping an)-.5 F 1.621(ything that is not a simple v)-.15 F
(ariable.)-.25 E .84(This is because)128 300 R F1 .84
(chomp $cwd = \222pwd\222;)3.34 F F0 .84(is interpreted as)3.34 F F1 .84
(\(chomp $cwd\) = \222pwd\222;)3.34 F F0 3.34(,r)C(ather)-3.34 E 1.765
(than as)128 312 R F1 1.765(chomp\( $cwd = \222pwd\222 \))4.265 F F0
1.765(which you might e)4.265 F 4.264(xpect. Similarly)-.15 F(,)-.65 E
F1 1.764(chomp $a, $b)4.264 F F0(is)4.264 E(interpreted as)128 324 Q F1
(chomp\($a\), $b)2.5 E F0(rather than as)2.5 E F1(chomp\($a, $b\))2.5 E
F0(.)A(chop)108 340.8 Q F3 -1.215(VA)2.5 G(RIABLE)1.215 E F0(chop\()108
352.8 Q F3(LIST)2.5 E F0(\))2.5 E(chop)108 364.8 Q .953(Chops of)128
376.8 R 3.453(ft)-.25 G .953
(he last character of a string and returns the character chopped.)-3.453
F .954(It is much more ef)5.954 F(\214cient)-.25 E(than)128 388.8 Q F1
(s/.$//s)3.1 E F0 .6(because it neither scans nor copies the string.)3.1
F(If)5.6 E F3 -1.215(VA)3.1 G(RIABLE)1.215 E F0 .6(is omitted, chops)3.1
F F1($_)3.1 E F0 5.6(.I)C(f)-5.6 E F3 -1.215(VA)128 400.8 S(RIABLE)1.215
E F0(is a hash, it chops the hash')2.5 E 2.5(sv)-.55 G(alues, b)-2.75 E
(ut not its k)-.2 E -.15(ey)-.1 G(s.).15 E -1.1(Yo)128 418.8 S 2.5(uc)
1.1 G(an actually chop an)-2.5 E(ything that')-.15 E 2.5(sa)-.55 G 2.5
(nl)-2.5 G -.25(va)-2.5 G(lue, including an assignment.).25 E
(If you chop a list, each element is chopped.)128 436.8 Q(Only the v)5 E
(alue of the last)-.25 E F1(chop)2.5 E F0(is returned.)2.5 E 6.331
(Note that)128 454.8 R F1(chop)8.831 E F0 6.331
(returns the last character)8.831 F 11.331(.T)-.55 G 8.831(or)-12.131 G
6.332(eturn all b)-8.831 F 6.332(ut the last character)-.2 F 8.832(,u)
-.4 G(se)-8.832 E F1(substr\($string, 0, \2551\))128 466.8 Q F0(.)A
(See also `)128 484.8 Q(`chomp')-.74 E('.)-.74 E(cho)108 501.6 Q(wn)-.25
E F3(LIST)2.5 E F0 .148(Changes the o)128 513.6 R .148
(wner \(and group\) of a list of \214les.)-.25 F .147(The \214rst tw)
5.148 F 2.647(oe)-.1 G .147(lements of the list must be the)-2.647 F F2
(numeric)2.647 E F0 .307(uid and gid, in that order)128 525.6 R 5.307
(.A)-.55 G -.25(va)-2.5 G .308
(lue of \2551 in either position is interpreted by most systems to lea)
.25 F .608 -.15(ve t)-.2 H(hat).15 E -.25(va)128 537.6 S(lue unchanged.)
.25 E(Returns the number of \214les successfully changed.)5 E F1
($cnt = chown $uid, $gid, \010foo\010, \010bar\010;)152 555.6 Q
(chown $uid, $gid, @filenames;)152 567.6 Q F0 .49
(On systems that support)128 585.6 R F2(fc)2.99 E(hown)-.15 E F0 .49
(\(2\), you may pass \214lehandles among the \214les.)1.666 F .489
(On systems that don')5.489 F(t)-.18 E(support)128 597.6 Q F2(fc)3.705 E
(hown)-.15 E F0 1.205(\(2\), passing \214lehandles raises an e)1.666 F
3.706(xception. Filehandles)-.15 F 1.206(must be passed as globs or)
3.706 F(glob references to be recognized; bare)128 609.6 Q -.1(wo)-.25 G
(rds are considered \214lenames.).1 E(Here')128 627.6 Q 2.5(sa)-.55 G
2.5(ne)-2.5 G
(xample that looks up nonnumeric uids in the passwd \214le:)-2.65 E F1
(print "User: ";)152 645.6 Q(chomp\($user = <STDIN>\);)152 657.6 Q
(print "Files: ";)152 669.6 Q(chomp\($pattern = <STDIN>\);)152 681.6 Q
(\($login,$pass,$uid,$gid\) = getpwnam\($user\))152 705.6 Q
(or die "$user not in passwd file";)176 717.6 Q F0(perl v5.14.2)72 768 Q
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
(uted Perl Documentation)-.2 E(PERLFUNC\(1\))95.355 E/F1 10/Courier@0 SF
(@ary = glob\($pattern\);)152 84 Q 6(#e)12 G(xpand filenames)-6 E
(chown $uid, $gid, @ary;)152 96 Q F0 .351
(On most systems, you are not allo)128 114 R .351(wed to change the o)
-.25 F .35(wnership of the \214le unless you')-.25 F .35
(re the superuser)-.5 F(,)-.4 E 1.909
(although you should be able to change the group to an)128 126 R 4.41
(yo)-.15 G 4.41(fy)-4.41 G 1.91(our secondary groups.)-4.41 F 1.91
(On insecure)6.91 F .684(systems, these restrictions may be relax)128
138 R .684(ed, b)-.15 F .684(ut this is not a portable assumption.)-.2 F
(On)5.684 E/F2 9/Times-Roman@0 SF(POSIX)3.184 E F0(systems,)3.183 E
(you can detect this condition this w)128 150 Q(ay:)-.1 E F1
(use POSIX qw\(sysconf _PC_CHOWN_RESTRICTED\);)152 168 Q
($can_chown_giveaway = not sysconf\(_PC_CHOWN_RESTRICTED\);)152 180 Q F0
(chr)108 196.8 Q F2(NUMBER)2.5 E F0(chr)108 208.8 Q 1.146
(Returns the character represented by that)128 208.8 R F2(NUMBER)3.646 E
F0 1.146(in the character set.)3.646 F -.15(Fo)6.147 G 3.647(re).15 G
(xample,)-3.797 E F1(chr\(65\))3.647 E F0(is)3.647 E F1("A")128 220.8 Q
F0(in either)2.5 E F2(ASCII)2.5 E F0
(or Unicode, and chr\(0x263a\) is a Unicode smile)2.5 E 2.5(yf)-.15 G
(ace.)-2.6 E(Ne)128 238.8 Q -.05(ga)-.15 G(ti).05 E .557 -.15(ve v)-.25
H .257(alues gi)-.1 F .556 -.15(ve t)-.25 H .256
(he Unicode replacement character \().15 F/F3 10/Times-Italic@0 SF -.15
(ch)C(r).15 E F0(\(0xf)1.666 E -.25(ff)-.25 G .256(d\)\), e).25 F .256
(xcept under the bytes pragma,)-.15 F(where the lo)128 250.8 Q 2.5(we)
-.25 G(ight bits of the v)-2.5 E(alue \(truncated to an inte)-.25 E
(ger\) are used.)-.15 E(If)128 268.8 Q F2(NUMBER)2.5 E F0
(is omitted, uses)2.5 E F1($_)2.5 E F0(.)A -.15(Fo)128 286.8 S 2.5(rt)
.15 G(he re)-2.5 E -.15(ve)-.25 G(rse, use `).15 E(`ord')-.74 E('.)-.74
E 1.035(Note that characters from 128 to 255 \(inclusi)128 304.8 R -.15
(ve)-.25 G 3.535(\)a).15 G 1.035(re by def)-3.535 F 1.035
(ault internally not encoded as)-.1 F F2(UTF\2558)3.536 E F0(for)3.536 E
(backw)128 316.8 Q(ard compatibility reasons.)-.1 E
(See perlunicode for more about Unicode.)128 334.8 Q(chroot)108 351.6 Q
F2(FILEN)2.5 E(AME)-.315 E F0(chroot)108 363.6 Q .238(This function w)
128 375.6 R .238(orks lik)-.1 F 2.738(et)-.1 G .237
(he system call by the same name: it mak)-2.738 F .237
(es the named directory the ne)-.1 F 2.737(wr)-.25 G(oot)-2.737 E .294
(directory for all further pathnames that be)128 387.6 R .294
(gin with a)-.15 F F1(/)2.794 E F0 .294
(by your process and all its children.)2.794 F .294(\(It doesn')5.294 F
(t)-.18 E 2.963(change your current w)128 399.6 R 2.963
(orking directory)-.1 F 5.462(,w)-.65 G 2.962(hich is unaf)-5.462 F
5.462(fected.\) F)-.25 F 2.962(or security reasons, this call is)-.15 F
(restricted to the superuser)128 411.6 Q 5(.I)-.55 G(f)-5 E F2(FILEN)2.5
E(AME)-.315 E F0(is omitted, does a)2.5 E F1(chroot)2.5 E F0(to)2.5 E F1
($_)2.5 E F0(.)A(close)108 428.4 Q F2(FILEHANDLE)2.5 E F0(close)108
440.4 Q .454(Closes the \214le or pipe associated with the \214lehandle\
, \215ushes the)128 452.4 R F2(IO)2.954 E F0 -.2(bu)2.954 G -.25(ff).2 G
.454(ers, and closes the system \214le).25 F(descriptor)128 464.4 Q
5.546(.R)-.55 G .546
(eturns true if those operations succeed and if no error w)-5.546 F .545
(as reported by an)-.1 F 3.045(yP)-.15 G .545(erlIO layer)-3.045 F(.)
-.55 E(Closes the currently selected \214lehandle if the ar)128 476.4 Q
(gument is omitted.)-.18 E -1.1(Yo)128 494.4 S 2.618(ud)1.1 G(on')-2.618
E 2.618(th)-.18 G -2.25 -.2(av e)-2.618 H .119(to close)2.819 F F2
(FILEHANDLE)2.619 E F0 .119(if you are immediately going to do another)
2.619 F F1(open)2.619 E F0 .119(on it, because)2.619 F F1(open)128 506.4
Q F0 1.387(closes it for you.)3.888 F(\(See)6.387 E F1(open)3.887 E F0
3.887(.\) Ho)B(we)-.25 E -.15(ve)-.25 G 2.187 -.4(r, a).15 H 3.887(ne).4
G(xplicit)-4.037 E F1(close)3.887 E F0 1.387
(on an input \214le resets the line)3.887 F(counter \()128 518.4 Q F1
($.)A F0(\), while the implicit close done by)A F1(open)2.5 E F0
(does not.)2.5 E 1.087(If the \214lehandle came from a piped open,)128
536.4 R F1(close)3.587 E F0 1.087(returns f)3.587 F 1.087
(alse if one of the other syscalls in)-.1 F -.2(vo)-.4 G(lv).2 E(ed)-.15
E -.1(fa)128 548.4 S .173(ils or if its program e).1 F .173
(xits with non-zero status.)-.15 F .173(If the only problem w)5.173 F
.172(as that the program e)-.1 F .172(xited non-)-.15 F(zero,)128 560.4
Q F1($!)2.868 E F0 .368(will be set to)5.368 F F1(0)2.868 E F0 5.368(.C)
C .368(losing a pipe also w)-5.368 F .369(aits for the process e)-.1 F
-.15(xe)-.15 G .369(cuting on the pipe to e).15 F -.834(xit \212 in)-.15
F .141(case you wish to look at the output of the pipe afterw)128 572.4
R -.834(ards \212 and)-.1 F .141(implicitly puts the e)2.641 F .141
(xit status v)-.15 F .141(alue of)-.25 F(that command into)128 584.4 Q
F1($?)2.5 E F0(and)2.5 E F1(${^CHILD_ERROR_NATIVE})2.5 E F0(.)A .875
(If there are multiple threads running,)128 602.4 R F1(close)3.375 E F0
.876(on a \214lehandle from a piped open returns true without)3.376 F
-.1(wa)128 614.4 S(iting for the child process to terminate, if the \
\214lehandle is still open in another thread.).1 E .058(Closing the rea\
d end of a pipe before the process writing to it at the other end is do\
ne writing results in)128 632.4 R .823(the writer recei)128 644.4 R .823
(ving a)-.25 F F2(SIGPIPE)3.323 E F0 5.823(.I)C 3.323(ft)-5.823 G .823
(he other end can')-3.323 F 3.324(th)-.18 G .824
(andle that, be sure to read all the data before)-3.324 F
(closing the pipe.)128 656.4 Q(Example:)128 674.4 Q(perl v5.14.2)72 768
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
(uted Perl Documentation)-.2 E(PERLFUNC\(1\))95.355 E/F1 10/Courier@0 SF
(open\(OUTPUT, \010|sort >foo\010\))152 84 Q 6(#p)12 G(ipe to sort)-6 E
(or die "Can\010t start sort: $!";)176 96 Q 138(#... #)152 108 R
(print stuff to output)6 E(close OUTPUT)152 120 Q 6(#w)96 G
(ait for sort to finish)-6 E(or warn $! ? "Error closing sort pipe: $!")
176 132 Q 6(:")242 144 S(Exit status $? from sort";)-6 E
(open\(INPUT, \010foo\010\))152 156 Q 6(#g)60 G(et sort\010s results)-6
E(or die "Can\010t open \010foo\010 for input: $!";)176 168 Q/F2 9
/Times-Roman@0 SF(FILEHANDLE)128 186 Q F0 .145(may be an e)2.646 F .145
(xpression whose v)-.15 F .145
(alue can be used as an indirect \214lehandle, usually the real)-.25 F
(\214lehandle name or an auto)128 198 Q(vi)-.15 E(vi\214ed handle.)-.25
E(closedir)108 214.8 Q F2(DIRHANDLE)2.5 E F0
(Closes a directory opened by)128 226.8 Q F1(opendir)2.5 E F0
(and returns the success of that system call.)2.5 E(connect)108 243.6 Q
F2(SOCKET)2.5 E F0(,N)A(AME)-.35 E 2.102
(Attempts to connect to a remote sock)128 255.6 R 2.102(et, just lik)-.1
F(e)-.1 E/F3 10/Times-Italic@0 SF(connect)4.602 E F0 4.602
(\(2\). Returns)1.666 F 2.103(true if it succeeded, f)4.602 F(alse)-.1 E
(otherwise.)128 267.6 Q F2 -.315(NA)5.079 G(ME).315 E F0 .079
(should be a pack)2.579 F .079
(ed address of the appropriate type for the sock)-.1 F 2.578(et. See)-.1
F .078(the e)2.578 F(xamples)-.15 E(in `)128 279.6 Q(`Sock)-.74 E
(ets: Client/Serv)-.1 E(er Communication')-.15 E 2.5('i)-.74 G 2.5(np)
-2.5 G(erlipc.)-2.5 E(continue)108 296.4 Q F2(BLOCK)2.5 E F0(continue)
108 308.4 Q F1(continue)128 320.4 Q F0 2.031(is actually a \215o)4.531 F
4.531(wc)-.25 G 2.031(ontrol statement rather than a function.)-4.531 F
2.032(If there is a)7.032 F F1(continue)4.532 E F2(BLOCK)128 332.4 Q F0
.858(attached to a)3.358 F F2(BLOCK)3.358 E F0 .858(\(typically in a)
3.358 F F1(while)3.357 E F0(or)3.357 E F1(foreach)3.357 E F0 .857
(\), it is al)B -.1(wa)-.1 G .857(ys e).1 F -.15(xe)-.15 G .857
(cuted just before).15 F .513(the conditional is about to be e)128 344.4
R -.25(va)-.25 G .514(luated ag).25 F .514(ain, just lik)-.05 F 3.014
(et)-.1 G .514(he third part of a)-3.014 F F1(for)3.014 E F0 .514
(loop in C.)3.014 F .514(Thus it can)5.514 F .513
(be used to increment a loop v)128 356.4 R .513(ariable, e)-.25 F -.15
(ve)-.25 G 3.013(nw).15 G .513(hen the loop has been continued via the)
-3.013 F F1(next)3.013 E F0(statement)3.012 E
(\(which is similar to the C)128 368.4 Q F1(continue)2.5 E F0
(statement\).)2.5 E F1(last)128 386.4 Q F0(,)A F1(next)2.555 E F0 2.555
(,o)C(r)-2.555 E F1(redo)2.555 E F0 .055(may appear within a)2.555 F F1
(continue)2.555 E F0(block;)2.555 E F1(last)2.555 E F0(and)2.555 E F1
(redo)2.555 E F0(beha)2.556 E .356 -.15(ve a)-.2 H 2.556(si).15 G 2.556
(ft)-2.556 G(he)-2.556 E 2.556(yh)-.15 G(ad)-2.556 E .621(been e)128
398.4 R -.15(xe)-.15 G .621(cuted within the main block.).15 F .621
(So will)5.621 F F1(next)3.121 E F0 3.121(,b)C .62(ut since it will e)
-3.321 F -.15(xe)-.15 G .62(cute a).15 F F1(continue)3.12 E F0 .62
(block, it)3.12 F(may be more entertaining.)128 410.4 Q F1
(while \(EXPR\) {)152 428.4 Q(### redo always comes here)176 440.4 Q
(do_something;)176 452.4 Q 6(}c)152 464.4 S(ontinue {)-6 E
(### next always comes here)176 476.4 Q(do_something_else;)176 488.4 Q 6
(#t)176 500.4 S(hen back the top to re\255check EXPR)-6 E(})152 512.4 Q
(### last always comes here)152 524.4 Q F0 .2(Omitting the)128 542.4 R
F1(continue)2.7 E F0 .2(section is equi)2.7 F -.25(va)-.25 G .201
(lent to using an empty one, logically enough, so).25 F F1(next)2.701 E
F0(goes)2.701 E
(directly back to check the condition at the top of the loop.)128 554.4
Q .049(If the)128 572.4 R F1("switch")2.549 E F0 .048
(feature is enabled,)2.548 F F1(continue)2.548 E F0 .048
(is also a function that f)2.548 F .048(alls through the current)-.1 F
F1(when)2.548 E F0(or)128 584.4 Q F1(default)4.658 E F0 2.158
(block instead of iterating a dynamically enclosing)4.658 F F1(foreach)
4.659 E F0 2.159(or e)4.659 F 2.159(xiting a le)-.15 F(xically)-.15 E
(enclosing)128 596.4 Q F1(given)2.5 E F0 5(.S)C(ee feature and `)-5 E
(`Switch statements')-.74 E 2.5('i)-.74 G 2.5(np)-2.5 G
(erlsyn for more information.)-2.5 E(cos)108 613.2 Q F2(EXPR)2.5 E F0
(cos)108 625.2 Q(Returns the cosine of)128 625.2 Q F2(EXPR)2.5 E F0(\(e)
2.5 E(xpressed in radians\).)-.15 E(If)5 E F2(EXPR)2.5 E F0
(is omitted, tak)2.5 E(es the cosine of)-.1 E F1($_)2.5 E F0(.)A -.15
(Fo)128 643.2 S 4.168(rt).15 G 1.668(he in)-4.168 F -.15(ve)-.4 G 1.668
(rse cosine operation, you may use the).15 F F1(Math::Trig::acos\(\))
4.168 E F0 1.667(function, or use this)4.167 F(relation:)128 655.2 Q F1
(sub acos { atan2\( sqrt\(1 \255 $_[0] * $_[0]\), $_[0] \) })152 673.2 Q
F0(crypt)108 690 Q F2(PLAINTEXT)2.5 E F0(,SAL)A(T)-.92 E .734
(Creates a digest string e)128 702 R .734(xactly lik)-.15 F 3.234(et)-.1
G(he)-3.234 E F3(crypt)3.234 E F0 .734
(\(3\) function in the C library \(assuming that you actually)1.666 F
(ha)128 714 Q .3 -.15(ve a ve)-.2 H(rsion there that has not been e).15
E(xtirpated as a potential munition\).)-.15 E(perl v5.14.2)72 768 Q
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128 138 R 1.167(This function isn')6.167 F 3.667(ta)-.18 G 1.168
(ll that useful for cryptograph)-3.667 F 3.668(y\()-.05 G 1.168
(for that, look for)-3.668 F F1(Crypt)128 150 Q F0 .483
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2.577(op)-.1 G .077(ieces of te)-2.577 F .077
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174 R -.15(ex)3.385 G .885(ample is checking if a correct passw).15 F
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(digest of the passw)3.385 F .884(ord is stored,)-.1 F .393
(not the passw)128 186 R .393(ord itself.)-.1 F .394
(The user types in a passw)5.393 F .394(ord that is)-.1 F F1(crypt\(\))
2.894 E F0 1.394 -.5('d w)D .394(ith the same salt as the stored).5 F
2.5(digest. If)128 198 R(the tw)2.5 E 2.5(od)-.1 G
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216 R .314(erifying an e)-.15 F .313
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($digest\) eq $digest)128 228 R F0 2.76(\). The)B F2(SAL)2.76 E(T)-.828
E F0 .26(used to create the digest is visible as part of the digest.)
2.76 F(This)5.26 E(ensures)128 240 Q F1(crypt\(\))3.722 E F0 1.222
(will hash the ne)3.722 F 3.722(ws)-.25 G 1.222
(tring with the same salt as the digest.)-3.722 F 1.221(This allo)6.221
F 1.221(ws your code to)-.25 F -.1(wo)128 252 S .548
(rk with the standard crypt and with more e).1 F .548
(xotic implementations.)-.15 F .548(In other w)5.548 F .548
(ords, assume nothing)-.1 F
(about the returned string itself nor about ho)128 264 Q 2.5(wm)-.25 G
(an)-2.5 E 2.5(yb)-.15 G(ytes of)-2.5 E F2(SAL)2.5 E(T)-.828 E F0
(may matter)2.5 E(.)-.55 E -.35(Tr)128 282 S .15
(aditionally the result is a string of 13 bytes: tw).35 F 2.65<6f8c>-.1
G .15(rst bytes of the salt, follo)-2.65 F .15(wed by 11 bytes from the)
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128 318 Q(ferent strings.)-.25 E .848(When choosing a ne)128 336 R 3.348
(ws)-.25 G .849(alt create a random tw)-3.348 F 3.349(oc)-.1 G .849
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([./0\2559A\255Za\255z])128 348 Q F0(\(lik)3.847 E(e)-.1 E F3 1.346(joi\
n \010\010, \(\010.\010, \010/\010, 0..9, \010A\010..\010Z\010, \010a\
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(\). This)B .333
(set of characters is just a recommendation; the characters allo)2.832 F
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(sc)-.55 G(rypt library)-2.5 E 2.5(,a)-.65 G(nd Perl can')-2.5 E 2.5(tr)
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(Here')128 390 Q 2.5(sa)-.55 G 2.5(ne)-2.5 G(xample that mak)-2.65 E
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($pwd = \(getpwuid\($<\)\)[1];)152 408 Q(system "stty \255echo";)152 432
Q(print "Password: ";)152 444 Q(chomp\($word = <STDIN>\);)152 456 Q
(print "\\n";)152 468 Q(system "stty echo";)152 480 Q
(if \(crypt\($word, $pwd\) ne $pwd\) {)152 504 Q(die "Sorry...\\n";)176
516 Q 6(}e)152 528 S(lse {)-6 E(print "ok\\n";)176 540 Q(})152 552 Q F0
(Of course, typing in your o)128 570 Q(wn passw)-.25 E(ord to whoe)-.1 E
-.15(ve)-.25 G 2.5(ra).15 G(sks you for it is unwise.)-2.5 E .437
(The crypt function is unsuitable for hashing lar)128 588 R .437
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E(get the information back.)128 600 Q
(Look at the Digest module for more rob)5 E(ust algorithms.)-.2 E .121
(If using)128 618 R F1(crypt\(\))2.621 E F0 .121
(on a Unicode string \(which)2.621 F F1(potentially)2.621 E F0 .122
(has characters with codepoints abo)2.621 F .422 -.15(ve 2)-.15 H .122
(55\), Perl).15 F .615(tries to mak)128 630 R 3.115(es)-.1 G .614
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1.22(of the hash.)128 126 R(\(Unlik)6.22 E 3.72(en)-.1 G(ormal)-3.72 E
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(one\).)128 138 Q F1(DBN)5.211 E(AME)-.315 E F0 .211
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2.71 E F3(.pa)2.71 E(g)-.1 E F0 -.15(ex)2.71 G .21(tension if an).15 F
2.71(y\). If)-.15 F .21(the database)2.71 F .788(does not e)128 150 R
.789(xist, it is created with protection speci\214ed by)-.15 F F1(MASK)
3.289 E F0 .789(\(as modi\214ed by the)3.289 F F2(umask)3.289 E F0 3.289
(\). If)B(your)3.289 E 2.234(system supports only the older)128 162 R F1
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setting a dummy hash entry inside an).1 F F2(eval)128 228 Q F0
(to trap the error)2.5 E(.)-.55 E .624(Note that functions such as)128
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(while \(\($key,$val\) = each %HIST\) {)152 300 Q
(print $key, \010 = \010, unpack\(\010L\010,$val\), "\\n";)176 312 Q(})
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(dbmopen\(%NS_Hist, "$ENV{HOME}/.netscape/history.db"\))152 414 Q
(or die "Can\010t open netscape history file: $!";)176 426 Q F0(def)108
442.8 Q(ault)-.1 E F1(BLOCK)2.5 E F0 -.4(Wi)128 454.8 S 1.706(thin a).4
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(if \(@an_array\) { print "has array elements\\n" })152 84 Q
(if \(%a_hash\))152 96 Q 6({p)18 G(rint "has hash members\\n")-6 E(})18
E F0 .625(When used on a hash element, it tells you whether the v)128
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F1(print if defined $switch{D};)152 162 Q
(print "$val\\n" while defined\($val = pop\(@ary\)\);)152 174 Q
(die "Can\010t readlink $sym: $!")152 186 Q
(unless defined\($value = readlink $sym\);)176 198 Q
(sub foo { defined &$bar ? &$bar\(@_\) : die "No bar"; })152 210 Q
($debugging = 0 unless defined $debugging;)152 222 Q F0 2.717(Note: Man)
128 240 R 2.717(yf)-.15 G .217(olks tend to o)-2.717 F -.15(ve)-.15 G
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2.718 E F0(and)2.718 E F1("")128 252 Q F0
(\(the zero-length string\) are, in f)2.5 E(act, de\214ned v)-.1 E 2.5
(alues. F)-.25 F(or e)-.15 E(xample, if you say)-.15 E F1
("ab" =~ /a\(.*\)b/;)152 270 Q F0 .514(The pattern match succeeds and)
128 288 R F1($1)3.013 E F0 .513(is de\214ned, although it matched `)
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G .513(eally f)-3.013 F .513(ail to)-.1 F .988(match an)128 300 R 3.488
(ything. Rather)-.15 F 3.488(,i)-.4 G 3.488(tm)-3.488 G .989
(atched something that happened to be zero characters long.)-3.488 F
.989(This is all)5.989 F -.15(ve)128 312 S 1.11(ry abo).15 F -.15(ve)
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(When a function returns an unde\214ned v)6.11 F 1.11(alue, it')-.25 F
3.61(sa)-.55 G 3.61(na)-3.61 G 1.11(dmission that it)-3.61 F(couldn')128
324 Q 2.605(tg)-.18 G -2.15 -.25(iv e)-2.605 H .105
(you an honest answer)2.855 F 5.105(.S)-.55 G 2.605(oy)-5.105 G .105
(ou should use)-2.605 F F1(defined)2.605 E F0 .106
(only when questioning the inte)2.606 F(grity)-.15 E(of what you')128
336 Q(re trying to do.)-.5 E(At other times, a simple comparison to)5 E
F1(0)2.5 E F0(or)2.5 E F1("")2.5 E F0(is what you w)2.5 E(ant.)-.1 E
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(xpression that speci\214es an element or slice of a hash,)-5.054 F F1
(delete)4.904 E F0 2.404(deletes the speci\214ed)4.904 F .312
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(ex)2.812 G(ists\(\)).2 E F0 .312
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(xt. The)-.15 F .262(return list')128 436.8 R 2.762(sl)-.55 G .263
(ength al)-2.762 F -.1(wa)-.1 G .263(ys matches that of the ar).1 F .263
(gument list: deleting non-e)-.18 F .263(xistent elements returns the)
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(may also be used on arrays and array slices, b)2.714 F .213
(ut its beha)-.2 F .213(vior is less straightforw)-.2 F 2.713
(ard. Although)-.1 F F3 -.2(ex)128 478.8 S(ists\(\)).2 E F0 .706
(will return f)3.206 F .706
(alse for deleted entries, deleting array elements ne)-.1 F -.15(ve)-.25
G 3.207(rc).15 G .707(hanges indices of e)-3.207 F(xisting)-.15 E -.25
(va)128 490.8 S .584(lues; use).25 F F3(shift\(\))3.084 E F0(or)3.084 E
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(ll deleted elements f)-3.084 F .583(all at the end of an array)-.1 F
3.083(,t)-.65 G(he)-3.083 E(array')128 502.8 Q 2.709(ss)-.55 G .209(ize\
 shrinks to the position of the highest element that still tests true f\
or)-2.709 F F3 -.2(ex)2.709 G(ists\(\)).2 E F0 2.709(,o)C 2.709(rt)
-2.709 G 2.709(o0i)-2.709 G 2.709(fn)-2.709 G(one)-2.709 E(do.)128 514.8
Q/F4 9/Times-Bold@0 SF -1.08(WA)128 532.8 S(RNING:)1.08 E F0 .011
(Calling delete on array v)2.512 F .011(alues is deprecated and lik)-.25
F .011(ely to be remo)-.1 F -.15(ve)-.15 G 2.511(di).15 G 2.511(naf)
-2.511 G .011(uture v)-2.511 F .011(ersion of)-.15 F(Perl.)128 544.8 Q
.947(Deleting from)128 562.8 R F1(%ENV)3.447 E F0 .947
(modi\214es the en)3.447 F 3.447(vironment. Deleting)-.4 F .947
(from a hash tied to a)3.447 F F2(DBM)3.448 E F0 .948
(\214le deletes the)3.448 F .47(entry from the)128 574.8 R F2(DBM)2.97 E
F0 2.97(\214le. Deleting)2.97 F .47(from a)2.97 F F1(tied)2.97 E F0 .47
(hash or array may not necessarily return an)2.97 F .469(ything; it)-.15
F 1.092(depends on the implementation of the)128 586.8 R F1(tied)3.592 E
F0(package')3.592 E(s)-.55 E F2(DELETE)3.592 E F0 1.092
(method, which may do whate)3.592 F -.15(ve)-.25 G 3.592(ri).15 G(t)
-3.592 E(pleases.)128 598.8 Q(The)128 616.8 Q F1 .762(delete local EXPR)
3.262 F F0 .762
(construct localizes the deletion to the current block at run time.)
3.262 F(Until)5.762 E 1.99(the block e)128 628.8 R 1.991
(xits, elements locally deleted temporarily no longer e)-.15 F 4.491
(xist. See)-.15 F -.74(``)4.491 G 1.991(Localized deletion of).74 F
(elements of composite types')128 640.8 Q 2.5('i)-.74 G 2.5(np)-2.5 G
(erlsub)-2.5 E(.)-.4 E F1(%hash = \(foo => 11, bar => 22, baz => 33\);)
152 658.8 Q($scalar = delete $hash{foo};)152 670.8 Q 6(#$)78 G
(scalar is 11)-6 E($scalar = delete @hash{qw\(foo bar\)};)152 682.8 Q 6
(#$)30 G(scalar is 22)-6 E 6(@array =)152 694.8 R
(delete @hash{qw\(foo bar baz\)}; # @array)6 E(is \(undef,undef,33\))12
E F0(The follo)128 712.8 Q(wing \(inef)-.25 E
(\214ciently\) deletes all the v)-.25 E(alues of)-.25 E F1(%HASH)2.5 E
F0(and)2.5 E F1(@ARRAY:)2.5 E F0(perl v5.14.2)72 768 Q 198.17
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(foreach $key \(keys %HASH\) {)152 84 Q(delete $HASH{$key};)176 96 Q(})
152 108 Q(foreach $index \(0 .. $#ARRAY\) {)152 132 Q
(delete $ARRAY[$index];)176 144 Q(})152 156 Q F0(And so do these:)128
174 Q F1(delete @HASH{keys %HASH};)152 192 Q
(delete @ARRAY[0 .. $#ARRAY];)152 216 Q F0 1.59(But both are slo)128 234
R 1.589(wer than assigning the empty list or unde\214ning)-.25 F F1
(%HASH)4.089 E F0(or)4.089 E F1(@ARRAY)4.089 E F0 4.089(,w)C 1.589
(hich is the)-4.089 F(customary w)128 246 Q(ay to empty out an aggre)-.1
E -.05(ga)-.15 G(te:).05 E F1(%HASH = \(\);)152 264 Q 6(#c)30 G
(ompletely empty %HASH)-6 E(undef %HASH;)152 276 Q 6(#f)24 G
(orget %HASH ever existed)-6 E(@ARRAY = \(\);)152 300 Q 6(#c)24 G
(ompletely empty @ARRAY)-6 E(undef @ARRAY;)152 312 Q 6(#f)18 G
(orget @ARRAY ever existed)-6 E F0(The)128 330 Q/F2 9/Times-Roman@0 SF
(EXPR)4.291 E F0 1.791(can be arbitrarily complicated pro)4.291 F 1.791
(vided its \214nal operation is an element or slice of an)-.15 F(aggre)
128 342 Q -.05(ga)-.15 G(te:).05 E F1(delete $ref\255>[$x][$y]{$key};)
152 360 Q(delete @{$ref\255>[$x][$y]}{$key1, $key2, @morekeys};)152 372
Q(delete $ref\255>[$x][$y][$index];)152 396 Q
(delete @{$ref\255>[$x][$y]}[$index1, $index2, @moreindices];)152 408 Q
F0(die)108 424.8 Q F2(LIST)2.5 E F1(die)128 436.8 Q F0 2.093
(raises an e)4.593 F 2.093(xception. Inside an)-.15 F F1(eval)4.593 E F0
2.092(the error message is stuf)4.592 F 2.092(fed into)-.25 F F1($@)
4.592 E F0 2.092(and the)4.592 F F1(eval)4.592 E F0(is)4.592 E 1.748
(terminated with the unde\214ned v)128 448.8 R 4.248(alue. If)-.25 F
1.748(the e)4.248 F 1.748(xception is outside of all enclosing)-.15 F F1
(eval)4.248 E F0 1.748(s, then the)B 1.078(uncaught e)128 460.8 R 1.078
(xception prints)-.15 F F2(LIST)3.577 E F0(to)3.577 E F1(STDERR)3.577 E
F0 1.077(and e)3.577 F 1.077(xits with a non-zero v)-.15 F 1.077
(alue. If you need to e)-.25 F 1.077(xit the)-.15 F
(process with a speci\214c e)128 472.8 Q(xit code, see `)-.15 E(`e)-.74
E(xit')-.15 E('.)-.74 E(Equi)128 490.8 Q -.25(va)-.25 G(lent e).25 E
(xamples:)-.15 E F1(die "Can\010t cd to spool: $!\\n" unless chdir \010\
/usr/spool/news\010;)152 508.8 Q
(chdir \010/usr/spool/news\010 or die "Can\010t cd to spool: $!\\n")152
520.8 Q F0 1.197(If the last element of)128 538.8 R F2(LIST)3.697 E F0
1.197(does not end in a ne)3.697 F 1.198
(wline, the current script line number and input line)-.25 F .756
(number \(if an)128 550.8 R .756(y\) are also printed, and a ne)-.15 F
.755(wline is supplied.)-.25 F .755(Note that the `)5.755 F .755
(`input line number')-.74 F 3.255('\()-.74 G(also)-3.255 E(kno)128 562.8
Q .872(wn as `)-.25 F(`chunk')-.74 E .873('\) is subject to whate)-.74 F
-.15(ve)-.25 G 3.373(rn).15 G .873(otion of `)-3.373 F(`line')-.74 E
3.373('h)-.74 G .873(appens to be currently in ef)-3.373 F .873
(fect, and is)-.25 F(also a)128 574.8 Q -.25(va)-.2 G
(ilable as the special v).25 E(ariable)-.25 E F1($.)2.5 E F0 5(.S)C
(ee `)-5 E(`$/')-.74 E 2.5('i)-.74 G 2.5(np)-2.5 G(erlv)-2.5 E(ar and `)
-.25 E(`$.)-.74 E 1.48 -.74('' i)-.7 H 2.5(np).74 G(erlv)-2.5 E(ar)-.25
E(.)-.55 E .484(Hint: sometimes appending)128 592.8 R F1 .484
(", stopped")2.984 F F0 .483(to your message will cause it to mak)2.984
F 2.983(eb)-.1 G .483(etter sense when)-2.983 F(the string)128 604.8 Q
F1("at foo line 123")2.5 E F0(is appended.)2.5 E
(Suppose you are running script `)5 E(`canasta')-.74 E('.)-.74 E F1
(die "/etc/games is no good";)152 622.8 Q
(die "/etc/games is no good, stopped";)152 634.8 Q F0(produce, respecti)
128 652.8 Q -.15(ve)-.25 G(ly).15 E F1
(/etc/games is no good at canasta line 123.)152 670.8 Q
(/etc/games is no good, stopped at canasta line 123.)152 682.8 Q F0 .937
(If the output is empty and)128 700.8 R F1($@)3.437 E F0 .937
(already contains a v)3.437 F .937(alue \(typically from a pre)-.25 F
.938(vious e)-.25 F -.25(va)-.25 G .938(l\) that v).25 F .938(alue is)
-.25 F(reused after appending)128 712.8 Q F1("\\t...propagated")2.5 E F0
5(.T)C(his is useful for propag)-5 E(ating e)-.05 E(xceptions:)-.15 E
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(eval { ... };)152 84 Q(die unless $@ =~ /Expected exception/;)152 96 Q
F0 1.924(If the output is empty and)128 114 R F1($@)4.424 E F0 1.924
(contains an object reference that has a)4.424 F F1(PROPAGATE)4.423 E F0
1.923(method, that)4.423 F .692(method will be called with additional \
\214le and line number parameters.)128 126 R .692(The return v)5.692 F
.692(alue replaces the)-.25 F -.25(va)128 138 S .368(lue in).25 F F1($@)
2.868 E F0 5.368(;i)C .368(.e., as if)-5.368 F F1 .367
($@ = eval { $@\255>PROPAGATE\(_)2.867 F -4.334(_FILE_ _,)1.666 F 1.666
(__)6.367 G -4.334(LINE_ _\))-1.666 F(};)6.367 E F0(were)2.867 E
(called.)128 150 Q(If)128 168 Q F1($@)2.5 E F0(is empty then the string)
2.5 E F1("Died")2.5 E F0(is used.)2.5 E .601(If an uncaught e)128 186 R
.601(xception results in interpreter e)-.15 F .601(xit, the e)-.15 F
.601(xit code is determined from the v)-.15 F .602(alues of)-.25 F F1
($!)3.102 E F0(and)128 198 Q F1($?)2.5 E F0(with this pseudocode:)2.5 E
F1(exit $! if $!;)152 216 Q 6(#e)84 G(rrno)-6 E
(exit $? >> 8 if $? >> 8;)152 228 Q 6(#c)24 G(hild exit status)-6 E
(exit 255;)152 240 Q 6(#l)114 G(ast resort)-6 E F0 .502
(The intent is to squeeze as much possible information about the lik)128
258 R .501(ely cause into the limited space of)-.1 F .249(the system e)
128 270 R .249(xit code. Ho)-.15 F(we)-.25 E -.15(ve)-.25 G 1.049 -.4
(r, a).15 H(s).4 E F1($!)2.749 E F0 .249(is the v)2.749 F .249
(alue of C')-.25 F(s)-.55 E F1(errno)2.75 E F0 2.75(,w)C .25
(hich can be set by an)-2.75 F 2.75(ys)-.15 G .25(ystem call,)-2.75 F
.323(this means that the v)128 282 R .323(alue of the e)-.25 F .323
(xit code used by)-.15 F F1(die)2.823 E F0 .322
(can be non-predictable, so should not be relied)2.823 F
(upon, other than to be non-zero.)128 294 Q -1.1(Yo)128 312 S 3.081(uc)
1.1 G .581(an also call)-3.081 F F1(die)3.081 E F0 .581
(with a reference ar)3.081 F .581
(gument, and if this is trapped within an)-.18 F F1(eval)3.081 E F0(,)A
F1($@)3.082 E F0(contains)3.082 E .973(that reference.)128 324 R .973
(This permits more elaborate e)5.973 F .972
(xception handling using objects that maintain arbitrary)-.15 F .335
(state about the e)128 336 R 2.835(xception. Such)-.15 F 2.835(as)2.835
G .335(cheme is sometimes preferable to matching particular string v)
-2.835 F(alues)-.25 E(of)128 348 Q F1($@)2.788 E F0 .288(with re)2.788 F
.288(gular e)-.15 F 2.788(xpressions. Because)-.15 F F1($@)2.788 E F0
.288(is a global v)2.788 F .288(ariable and)-.25 F F1(eval)2.787 E F0
.287(may be used within object)2.787 F .58
(implementations, be careful that analyzing the error object doesn')128
360 R 3.08(tr)-.18 G .58(eplace the reference in the global)-3.08 F -.25
(va)128 372 S 4.551(riable. It').25 F 4.551(se)-.55 G 2.051
(asiest to mak)-4.551 F 4.551(eal)-.1 G 2.051(ocal cop)-4.551 F 4.551
(yo)-.1 G 4.551(ft)-4.551 G 2.05(he reference before an)-4.551 F 4.55
(ym)-.15 G 4.55(anipulations. Here')-4.55 F 4.55(sa)-.55 G(n)-4.55 E
-.15(ex)128 384 S(ample:).15 E F1(use Scalar::Util "blessed";)152 402 Q
(eval { ... ; die Some::Module::Exception\255>new\( FOO => "bar" \) };)
152 426 Q(if \(my $ev_err = $@\) {)152 438 Q(if \(blessed\($ev_err\) &&\
 $ev_err\255>isa\("Some::Module::Exception"\)\) {)176 450 Q 6(#h)200 462
S(andle Some::Module::Exception)-6 E(})176 474 Q(else {)176 486 Q 6(#h)
200 498 S(andle all other possible exceptions)-6 E(})176 510 Q(})152 522
Q F0 .21(Because Perl stringi\214es uncaught e)128 540 R .211
(xception messages before display)-.15 F 2.711(,y)-.65 G(ou')-2.711 E
.211(ll probably w)-.1 F .211(ant to o)-.1 F -.15(ve)-.15 G(rload).15 E
(stringi\214cation operations on e)128 552 Q(xception objects.)-.15 E
(See o)5 E -.15(ve)-.15 G(rload for details about that.).15 E -1.1(Yo)
128 570 S 5.767(uc)1.1 G 3.266
(an arrange for a callback to be run just before the)-5.767 F F1(die)
5.766 E F0 3.266(does its deed, by setting the)5.766 F F1 -4.334
($SIG{_ _DIE_ _})128 582 R F0 3.952(hook. The)3.952 F 1.453
(associated handler is called with the error te)3.952 F 1.453
(xt and can change the)-.15 F .288
(error message, if it sees \214t, by calling)128 594 R F1(die)2.788 E F0
(ag)2.788 E 2.788(ain. See)-.05 F -.74(``)2.788 G(%SIG').74 E 2.788('i)
-.74 G 2.788(np)-2.788 G(erlv)-2.788 E .287(ar for details on setting)
-.25 F F1(%SIG)2.787 E F0 .394(entries, and `)128 606 R(`e)-.74 E -.25
(va)-.25 G(l).25 E/F2 9/Times-Roman@0 SF(BLOCK)2.894 E F0 1.874 -.74
('' f)D .394(or some e).74 F 2.894(xamples. Although)-.15 F .394
(this feature w)2.894 F .395(as to be run only right before)-.1 F 1.323
(your program w)128 618 R 1.323(as to e)-.1 F 1.323
(xit, this is not currently so: the)-.15 F F1 -4.334($SIG{_ _DIE_ _})
3.822 F F0 1.322(hook is currently called)3.822 F -2.15 -.25(ev e)128
630 T 2.5(ni).25 G(nside)-2.5 E/F3 10/Times-Italic@0 SF -.15(ev)2.5 G
(al\(\)).15 E F0(ed blocks/strings!)A(If one w)5 E
(ants the hook to do nothing in such situations, put)-.1 E F1
(die @_ if $^S;)152 648 Q F0 1.874
(as the \214rst line of the handler \(see `)128 666 R(`$^S')-.74 E 4.375
('i)-.74 G 4.375(np)-4.375 G(erlv)-4.375 E 4.375(ar\). Because)-.25 F
1.875(this promotes strange action at a)4.375 F
(distance, this counterintuiti)128 678 Q .3 -.15(ve b)-.25 H(eha).15 E
(vior may be \214x)-.2 E(ed in a future release.)-.15 E(See also)128 696
Q F3 -.2(ex)2.5 G(it\(\)).2 E F0(,)A F3(warn\(\))2.5 E F0 2.5(,a)C
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.492(Returns the v)5.492 F .492
(alue of the last command in the sequence of commands indicated)-.25 F
(by)128 108 Q F1(BLOCK)2.764 E F0 5.264(.W)C .264(hen modi\214ed by the)
-5.264 F/F2 10/Courier@0 SF(while)2.764 E F0(or)2.764 E F2(until)2.765 E
F0 .265(loop modi\214er)2.765 F 2.765(,e)-.4 G -.15(xe)-2.915 G .265
(cutes the).15 F F1(BLOCK)2.765 E F0 .265(once before)2.765 F(testing t\
he loop condition. \(On other statements the loop modi\214ers test the \
conditional \214rst.\))128 120 Q F2 .237(do BLOCK)128 138 R F0(does)
2.737 E/F3 10/Times-Italic@0 SF(not)2.736 E F0 .236
(count as a loop, so the loop control statements)2.736 F F2(next)2.736 E
F0(,)A F2(last)2.736 E F0 2.736(,o)C(r)-2.736 E F2(redo)2.736 E F0 .236
(cannot be)2.736 F(used to lea)128 150 Q .3 -.15(ve o)-.2 H 2.5(rr).15 G
(estart the block.)-2.5 E(See perlsyn for alternati)5 E .3 -.15(ve s)
-.25 H(trate).15 E(gies.)-.15 E(do)108 166.8 Q F1(SUBR)2.5 E(OUTINE)-.36
E F0(\()A F1(LIST)A F0(\))A 1.125
(This form of subroutine call is deprecated.)128 178.8 R F1(SUBR)6.126 E
(OUTINE)-.36 E F0 1.126(can be a bare)3.626 F -.1(wo)-.25 G 1.126
(rd, a scalar v).1 F 1.126(ariable or a)-.25 F(subroutine be)128 190.8 Q
(ginning with)-.15 E F2(&)2.5 E F0(.)A(do)108 207.6 Q F1(EXPR)2.5 E F0
(Uses the v)128 219.6 Q(alue of)-.25 E F1(EXPR)2.5 E F0
(as a \214lename and e)2.5 E -.15(xe)-.15 G
(cutes the contents of the \214le as a Perl script.).15 E F2
(do \010stat.pl\010;)152 237.6 Q F0(is just lik)128 255.6 Q(e)-.1 E F2
(eval \222cat stat.pl\222;)152 273.6 Q F0 -.15(ex)128 291.6 S 1.6
(cept that it').15 F 4.1(sm)-.55 G 1.6(ore ef)-4.1 F 1.599
(\214cient and concise, k)-.25 F 1.599
(eeps track of the current \214lename for error messages,)-.1 F 1.193
(searches the)128 303.6 R F2(@INC)3.693 E F0 1.193
(directories, and updates)3.693 F F2(%INC)3.694 E F0 1.194
(if the \214le is found.)3.694 F 1.194(See `)6.194 F(`@INC')-.74 E 3.694
('i)-.74 G 3.694(np)-3.694 G(erlv)-3.694 E 1.194(ar and)-.25 F -.74(``)
128 315.6 S(%INC').74 E 3.792('i)-.74 G 3.792(np)-3.792 G(erlv)-3.792 E
1.292(ar for these v)-.25 F 3.791(ariables. It)-.25 F 1.291(also dif)
3.791 F 1.291(fers in that code e)-.25 F -.25(va)-.25 G 1.291
(luated with).25 F F2 1.291(do FILENAME)3.791 F F0 1.199(cannot see le)
128 327.6 R 1.199(xicals in the enclosing scope;)-.15 F F2 1.199
(eval STRING)3.699 F F0 3.699(does. It')3.699 F 3.7(st)-.55 G 1.2
(he same, ho)-3.7 F(we)-.25 E -.15(ve)-.25 G 2 -.4(r, i).15 H 3.7(nt).4
G 1.2(hat it)-3.7 F(does reparse the \214le e)128 339.6 Q -.15(ve)-.25 G
(ry time you call it, so you probably don').15 E 2.5(tw)-.18 G
(ant to do this inside a loop.)-2.6 E(If)128 357.6 Q F2(do)2.799 E F0
.299(can read the \214le b)2.799 F .299
(ut cannot compile it, it returns)-.2 F F2(undef)2.799 E F0 .298
(and sets an error message in)2.798 F F2($@)2.798 E F0 5.298(.I)C(f)
-5.298 E F2(do)2.798 E F0 .798
(cannot read the \214le, it returns undef and sets)128 369.6 R F2($!)
3.298 E F0 .798(to the error)3.298 F 5.799(.A)-.55 G -.1(lwa)-5.799 G
.799(ys check).1 F F2($@)3.299 E F0 .799(\214rst, as compilation)3.299 F
.689(could f)128 381.6 R .689(ail in a w)-.1 F .689(ay that also sets)
-.1 F F2($!)3.189 E F0 5.689(.I)C 3.189(ft)-5.689 G .689
(he \214le is successfully compiled,)-3.189 F F2(do)3.189 E F0 .689
(returns the v)3.189 F .689(alue of the)-.25 F(last e)128 393.6 Q
(xpression e)-.15 E -.25(va)-.25 G(luated.).25 E 1.654
(Inclusion of library modules is better done with the)128 411.6 R F2
(use)4.155 E F0(and)4.155 E F2(require)4.155 E F0 1.655
(operators, which also do)4.155 F
(automatic error checking and raise an e)128 423.6 Q(xception if there')
-.15 E 2.5(sap)-.55 G(roblem.)-2.5 E -1.1(Yo)128 441.6 S 2.972(um)1.1 G
.472(ight lik)-2.972 F 2.972(et)-.1 G 2.972(ou)-2.972 G(se)-2.972 E F2
(do)2.972 E F0 .472(to read in a program con\214guration \214le.)2.972 F
.471(Manual error checking can be done)5.471 F(this w)128 453.6 Q(ay:)
-.1 E F2 6(#r)152 471.6 S(ead in config files: system first, then user)
-6 E(for $file \("/share/prog/defaults.rc",)152 483.6 Q
("$ENV{HOME}/.someprogrc"\))218 495.6 Q({)152 507.6 Q
(unless \($return = do $file\) {)176 519.6 Q
(warn "couldn\010t parse $file: $@" if $@;)200 531.6 Q
(warn "couldn\010t do $file: $!")200 543.6 Q(unless defined $return;)24
E(warn "couldn\010t run $file")200 555.6 Q(unless $return;)42 E(})176
567.6 Q(})152 579.6 Q F0(dump)108 596.4 Q F1(LABEL)2.5 E F0(dump)108
608.4 Q 1.862(This function causes an immediate core dump.)128 620.4 R
1.862(See also the)6.862 F/F4 10/Times-Bold@0 SF<ad75>4.362 E F0 1.863
(command-line switch in perlrun,)4.362 F .462
(which does the same thing.)128 632.4 R .461
(Primarily this is so that you can use the)5.461 F F4(undump)2.961 E F0
.461(program \(not supplied\))2.961 F 1.738
(to turn your core dump into an e)128 644.4 R -.15(xe)-.15 G 1.739
(cutable binary after ha).15 F 1.739(ving initialized all your v)-.2 F
1.739(ariables at the)-.25 F(be)128 656.4 Q 2.034
(ginning of the program.)-.15 F 2.034(When the ne)7.034 F 4.534(wb)-.25
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(incoming-mail \214lter will cause the mailer to return the item undeli)
2.786 F -.15(ve)-.25 G .287(red, b).15 F .287(ut that')-.2 F 2.787(sn)
-.55 G .287(ot true)-2.787 F -2.15 -.25(ev e)128 340.8 T(rywhere.).25 E
(Don')128 358.8 Q 2.877(tu)-.18 G(se)-2.877 E F1(exit)2.877 E F0 .377
(to abort a subroutine if there')2.877 F 2.876(sa)-.55 G .676 -.15(ny c)
-2.876 H .376(hance that someone might w).15 F .376(ant to trap whate)
-.1 F -.15(ve)-.25 G(r).15 E(error happened.)128 370.8 Q(Use)5 E F1(die)
2.5 E F0(instead, which can be trapped by an)2.5 E F1(eval)2.5 E F0(.)A
(The)128 388.8 Q F2 -.2(ex)2.797 G(it\(\)).2 E F0 .297
(function does not al)2.797 F -.1(wa)-.1 G .297(ys e).1 F .297
(xit immediately)-.15 F 5.297(.I)-.65 G 2.798(tc)-5.297 G .298(alls an)
-2.798 F 2.798(yd)-.15 G(e\214ned)-2.798 E F1(END)2.798 E F0 .298
(routines \214rst, b)2.798 F .298(ut these)-.2 F F1(END)128 400.8 Q F0
.061(routines may not themselv)2.561 F .061(es abort the e)-.15 F 2.561
(xit. Lik)-.15 F -.25(ew)-.1 G .061(ise an).25 F 2.561(yo)-.15 G .06
(bject destructors that need to be called)-2.561 F .69
(are called before the real e)128 412.8 R(xit.)-.15 E F1(END)5.69 E F0
.691(routines and destructors can change the e)3.191 F .691
(xit status by modifying)-.15 F F1($?)128 424.8 Q F0 4.544(.I)C 4.544
(ft)-4.544 G 2.043(his is a problem, you can call)-4.544 F F1
(POSIX:_exit\($status\))4.543 E F0 2.043(to a)4.543 F -.2(vo)-.2 G(id).2
E F3(END)4.543 E F0 2.043(and destructor)4.543 F 2.5(processing. See)128
436.8 R(perlmod for details.)2.5 E -.15(ex)108 453.6 S(p).15 E F3(EXPR)
2.5 E F0 -.15(ex)108 465.6 S(p).15 E(Returns)128 465.6 Q F2(e)2.5 E F0
(\(the natural log)2.5 E(arithm base\) to the po)-.05 E(wer of)-.25 E F3
(EXPR)2.5 E F0 5(.I)C(f)-5 E F3(EXPR)2.5 E F0(is omitted, gi)2.5 E -.15
(ve)-.25 G(s).15 E F1(exp\($_\))2.5 E F0(.)A(fcntl)108 482.4 Q F3
(FILEHANDLE)2.5 E F0(,FUNCTION,SCALAR)A(Implements the)128 494.4 Q F2
(fcntl)2.5 E F0(\(2\) function.)1.666 E -1.1(Yo)5 G(u')1.1 E
(ll probably ha)-.1 E .3 -.15(ve t)-.2 H 2.5(os).15 G(ay)-2.5 E F1
(use Fcntl;)152 512.4 Q F0 1.342
(\214rst to get the correct constant de\214nitions.)128 530.4 R(Ar)6.342
E 1.342(gument processing and v)-.18 F 1.342(alue returned w)-.25 F
1.343(ork just lik)-.1 F(e)-.1 E F1(ioctl)128 542.4 Q F0(belo)2.5 E 3.8
-.65(w. F)-.25 H(or e).5 E(xample:)-.15 E F1(use Fcntl;)152 560.4 Q
(fcntl\($filehandle, F_GETFL, $packed_return_buffer\))152 572.4 Q
(or die "can\010t fcntl F_GETFL: $!";)176 584.4 Q F0 -1.1(Yo)128 602.4 S
3.3(ud)1.1 G(on')-3.3 E 3.3(th)-.18 G -2.25 -.2(av e)-3.3 H .8
(to check for)3.5 F F1(defined)3.3 E F0 .8(on the return from)3.3 F F1
(fcntl)3.3 E F0 5.8(.L)C(ik)-5.8 E(e)-.1 E F1(ioctl)3.3 E F0 3.3(,i)C
3.3(tm)-3.3 G .8(aps a)-3.3 F F1(0)3.3 E F0(return)3.3 E 1.023
(from the system call into)128 614.4 R F1 1.023("0 but true")3.523 F F0
1.023(in Perl.)3.523 F 1.023(This string is true in boolean conte)6.023
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(xception if used on a machine that doesn')-.15 F 3.378(ti)-.18 G
(mplement)-3.378 E F2(fcntl)3.378 E F0 3.378(\(2\). See)1.666 F(the)
3.378 E(Fcntl module or your)128 656.4 Q F2(fcntl)2.5 E F0
(\(2\) manpage to learn what functions are a)1.666 E -.25(va)-.2 G
(ilable on your system.).25 E(Here')128 674.4 Q 4.125(sa)-.55 G 4.125
(ne)-4.125 G 1.625(xample of setting a \214lehandle named)-4.275 F F1
(REMOTE)4.125 E F0 1.626(to be non-blocking at the system le)4.125 F
-.15(ve)-.25 G(l.).15 E -1.1(Yo)128 686.4 S(u')1.1 E(ll ha)-.1 E .3 -.15
(ve t)-.2 H 2.5(on).15 G -.15(eg)-2.5 G(otiate).15 E F1($|)2.5 E F0
(on your o)2.5 E(wn, though.)-.25 E F1
(use Fcntl qw\(F_GETFL F_SETFL O_NONBLOCK\);)152 704.4 Q
($flags = fcntl\(REMOTE, F_GETFL, 0\))152 728.4 Q F0(perl v5.14.2)72 768
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(or die "Can\010t get flags for the socket: $!\\n";)224 84 Q
($flags = fcntl\(REMOTE, F_SETFL, $flags | O_NONBLOCK\))152 108 Q
(or die "Can\010t set flags for the socket: $!\\n";)224 120 Q F0
(\214leno)108 136.8 Q/F2 9/Times-Roman@0 SF(FILEHANDLE)2.5 E F0 .138(Re\
turns the \214le descriptor for a \214lehandle, or unde\214ned if the \
\214lehandle is not open.)128 148.8 R .138(If there is no real)5.138 F
.521(\214le descriptor at the)128 160.8 R F2(OS)3.021 E F0(le)3.022 E
-.15(ve)-.25 G .522
(l, as can happen with \214lehandles connected to memory objects via).15
F F1(open)3.022 E F0(with a reference for the third ar)128 172.8 Q
(gument, \2551 is returned.)-.18 E 3.204
(This is mainly useful for constructing bitmaps for)128 190.8 R F1
(select)5.704 E F0 3.204(and lo)5.704 F(w-le)-.25 E -.15(ve)-.25 G(l).15
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202.8 R F2(FILEHANDLE)2.845 E F0 .345(is an e)2.845 F .345
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E F1(if \(fileno\(THIS\) == fileno\(THAT\)\) {)152 250.8 Q
(print "THIS and THAT are dups\\n";)176 262.8 Q(})152 274.8 Q F0
(\215ock)108 291.6 Q F2(FILEHANDLE)2.5 E F0(,OPERA)A(TION)-1.11 E(Calls)
128 303.6 Q/F3 10/Times-Italic@0 SF(\215oc)4.247 E(k)-.2 E F0 1.747
(\(2\), or an emulation of it, on)1.666 F F2(FILEHANDLE)4.246 E F0 6.746
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(ailure.)-.1 E 2.003(Produces a f)128 315.6 R 2.004
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(mplement)-4.504 E F3(\215oc)4.504 E(k)-.2 E F0(\(2\),)1.666 E F3(fcntl)
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-5.015 E(records.)128 339.6 Q -1 -.8(Tw o)128 357.6 T 1.262
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SF(mer)2.593 E .092(ely advisory)-.18 F F0 5.092(.S)C .092
(uch discretionary locks are more \215e)-5.092 F .092(xible, b)-.15 F
(ut)-.2 E(of)128 381.6 Q 1.93(fer fe)-.25 F 1.93(wer guarantees.)-.25 F
1.93(This means that programs that do not also use)6.93 F F1(flock)4.43
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F1(flock)3.05 E F0 5.549(.S)C .549(ee perlport, your port')-5.549 F
3.049(ss)-.55 G .549
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1.622(manpages for details.)128 405.6 R(It')6.622 E 4.122(sb)-.55 G
1.622(est to assume traditional beha)-4.122 F 1.622(vior if you')-.2 F
1.623(re writing portable programs.)-.5 F 3.366(\(But if you')128 417.6
R 3.366(re not, you should as al)-.5 F -.1(wa)-.1 G 3.365
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(s)-.55 E .394(idiosyncrasies \(sometimes called `)128 429.6 R
(`features')-.74 E 2.894('\). Sla)-.74 F .394
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(LOCK_SH)2.692 E F0(,)A F2(LOCK_EX)2.692 E F0 2.692(,o)C(r)-2.692 E F2
(LOCK_UN)2.692 E F0 2.692(,p)C .192(ossibly combined with)-2.692 F F2
(LOCK_NB)2.692 E F0 5.192(.T)C(hese)-5.192 E .043
(constants are traditionally v)128 471.6 R .043(alued 1, 2, 8 and 4, b)
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.333(from the Fcntl module, either indi)128 483.6 R(vidually)-.25 E
2.833(,o)-.65 G 2.833(ra)-2.833 G 2.833(sa)-2.833 G .332
(group using the)-.001 F F1(:flock)2.832 E F0(tag.)2.832 E F2(LOCK_SH)
5.332 E F0 .332(requests a)2.832 F .077(shared lock,)128 495.6 R F2
(LOCK_EX)2.577 E F0 .077(requests an e)2.577 F(xclusi)-.15 E .377 -.15
(ve l)-.25 H .077(ock, and).15 F F2(LOCK_UN)2.577 E F0 .077
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(flock)3.786 E F0 1.286(returns immediately rather)3.786 F
(than blocking w)128 519.6 Q
(aiting for the lock; check the return status to see if you got it.)-.1
E 4.885 -.8(To a)128 537.6 T -.2(vo).6 G 3.285
(id the possibility of miscoordination, Perl no).2 F 5.785<778d>-.25 G
(ushes)-5.785 E F2(FILEHANDLE)5.785 E F0 3.285(before locking or)5.785 F
(unlocking it.)128 549.6 Q 3.234(Note that the emulation b)128 567.6 R
3.234(uilt with)-.2 F F3(loc)5.734 E(kf)-.2 E F0 3.234(\(3\) doesn')
1.666 F 5.734(tp)-.18 G(ro)-5.734 E 3.234
(vide shared locks, and it requires that)-.15 F F2(FILEHANDLE)128 579.6
Q F0 .883(be open with write intent.)3.383 F .883
(These are the semantics that)5.883 F F3(loc)3.383 E(kf)-.2 E F0 .884
(\(3\) implements.)1.666 F .884(Most if)5.884 F 1.407
(not all systems implement)128 591.6 R F3(loc)3.907 E(kf)-.2 E F0 1.407
(\(3\) in terms of)1.666 F F3(fcntl)3.907 E F0 1.407
(\(2\) locking, though, so the dif)1.666 F 1.407(fering semantics)-.25 F
(shouldn')128 603.6 Q 2.5(tb)-.18 G(ite too man)-2.5 E 2.5(yp)-.15 G
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(\(2\) emulation of)1.666 F F3(\215oc)2.684 E(k)-.2 E F0 .184
(\(3\) requires that)1.666 F F2(FILEHANDLE)2.684 E F0 .184
(be open with read intent to use)2.684 F F2(LOCK_SH)128 633.6 Q F0
(and requires that it be open with write intent to use)2.5 E F2(LOCK_EX)
2.5 E F0(.)A .763(Note also that some v)128 651.6 R .763(ersions of)-.15
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E F3(\215oc)128 675.6 Q(k)-.2 E F0 4.473(\(2\) function, and so pro)
1.666 F 4.472(vide its o)-.15 F(wn)-.25 E F3(fcntl)6.972 E F0 4.472
(\(2\)\255based emulation, by passing the switch)1.666 F F1
(\255Ud_flock)128 687.6 Q F0(to the)2.5 E F3(Con\214gur)2.5 E(e)-.37 E
F0(program when you con\214gure and b)2.5 E(uild a ne)-.2 E 2.5(wP)-.25
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(use Fcntl qw\(:flock SEEK_END\); # import LOCK_* and SEEK_END constant\
s)152 84 Q(sub lock {)152 108 Q(my \($fh\) = @_;)176 120 Q
(flock\($fh, LOCK_EX\) or die "Cannot lock mailbox \255 $!\\n";)176 132
Q 6(#a)176 156 S(nd, in case someone appended while we were waiting...)
-6 E(seek\($fh, 0, SEEK_END\) or die "Cannot seek \255 $!\\n";)176 168 Q
(})152 180 Q(sub unlock {)152 204 Q(my \($fh\) = @_;)176 216 Q
(flock\($fh, LOCK_UN\) or die "Cannot unlock mailbox \255 $!\\n";)176
228 Q(})152 240 Q
(open\(my $mbox, ">>", "/usr/spool/mail/$ENV{\010USER\010}"\))152 264 Q
(or die "Can\010t open mailbox: $!";)176 276 Q(lock\($mbox\);)152 300 Q
(print $mbox $msg,"\\n\\n";)152 312 Q(unlock\($mbox\);)152 324 Q F0 .212
(On systems that support a real)128 342 R/F2 10/Times-Italic@0 SF
(\215oc)2.712 E(k)-.2 E F0 .212(\(2\), locks are inherited across)1.666
F F2(fork\(\))2.712 E F0 .212(calls, whereas those that must)2.712 F
1.471(resort to the more capricious)128 354 R F2(fcntl)3.97 E F0 1.47
(\(2\) function lose their locks, making it seriously harder to write)
1.666 F(serv)128 366 Q(ers.)-.15 E(See also DB_File for other)128 384 Q
F2(\215oc)2.5 E(k\(\))-.2 E F0 -.15(ex)2.5 G(amples.).15 E(fork)108
400.8 Q 1.024(Does a)128 412.8 R F2(fork)3.524 E F0 1.024
(\(2\) system call to create a ne)1.666 F 3.525(wp)-.25 G 1.025
(rocess running the same program at the same point.)-3.525 F(It)6.025 E
.115(returns the child pid to the parent process,)128 424.8 R F1(0)2.614
E F0 .114(to the child process, or)2.614 F F1(undef)2.614 E F0 .114
(if the fork is unsuccessful.)2.614 F .057(File descriptors \(and somet\
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(ve)-.25 G .058(rything else is copied.).15 F 2.695
(On most systems supporting)128 448.8 R F2(fork\(\))5.195 E F0 5.195(,g)
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king it the dominant paradigm for)-.1 F(multitasking o)128 472.8 Q -.15
(ve)-.15 G 2.5(rt).15 G(he last fe)-2.5 E 2.5(wd)-.25 G(ecades.)-2.5 E
(Be)128 490.8 Q 2.033(ginning with v5.6.0, Perl attempts to \215ush all\
 \214les opened for output before forking the child)-.15 F .324
(process, b)128 502.8 R .324
(ut this may not be supported on some platforms \(see perlport\).)-.2 F
1.925 -.8(To b)5.325 H 2.825(es).8 G .325(afe, you may need to)-2.825 F
(set)128 514.8 Q F1($|)2.653 E F0(\($A)2.653 E(UT)-.55 E .152
(OFLUSH in English\) or call the)-.18 F F1(autoflush\(\))2.652 E F0 .152
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(aiting on your children, you will accumulate zombies.)-3.002 F .403
(On some systems,)5.403 F 1.028(you can a)128 556.8 R -.2(vo)-.2 G 1.028
(id this by setting).2 F F1($SIG{CHLD})3.528 E F0(to)3.528 E F1
("IGNORE")3.528 E F0 6.028(.S)C 1.028(ee also perlipc for more e)-6.028
F 1.028(xamples of)-.15 F(forking and reaping morib)128 568.8 Q
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(ou e)-2.976 F .476(xit, then the remote serv)-.15 F .476
(er \(such as, say)-.15 F 2.976(,a)-.65 G F3(CGI)-.001 E F0 .475
(script or a)2.975 F .17
(backgrounded job launched from a remote shell\) w)128 610.8 R(on')-.1 E
2.671(tt)-.18 G .171(hink you')-2.671 F .171(re done.)-.5 F -1.1(Yo)
5.171 G 2.671(us)1.1 G .171(hould reopen those to)-2.671 F F2(/de)128
622.8 Q(v/null)-.15 E F0(if it')2.5 E 2.5(sa)-.55 G .3 -.15(ny i)-2.5 H
(ssue.).15 E(format)108 639.6 Q(Declare a picture format for use by the)
128 651.6 Q F1(write)2.5 E F0 2.5(function. F)2.5 F(or e)-.15 E(xample:)
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176 681.6 Q 24($str, $%,)212 693.6 R(\010$\010 . int\($num\))24 E(.)152
705.6 Q($str = "widget";)152 729.6 Q F0(perl v5.14.2)72 768 Q 198.17
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(,p)C 2.689(lacing the output into the format output)-5.189 F
(accumulator)128 178.8 Q(,)-.4 E F1($^A)2.835 E F0(\(or)2.835 E F1
($ACCUMULATOR)2.835 E F0 .335(in English\).)2.835 F(Ev)5.335 E(entually)
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(is done, the contents)2.834 F(of)128 190.8 Q F1($^A)3.066 E F0 .567
(are written to some \214lehandle.)3.066 F -1.1(Yo)5.567 G 3.067(uc)1.1
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(FILEHANDLE)2.5 E F0(getc)108 327.6 Q .456(Returns the ne)128 339.6 R
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Q(else {)152 429.6 Q
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152 453.6 Q($key = getc\(STDIN\);)152 477.6 Q(if \($BSD_STYLE\) {)152
501.6 Q(system "stty \255cbreak </dev/tty >/dev/tty 2>&1";)176 513.6 Q
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E(the address because you ha)128 436.8 Q .3 -.15(ve s)-.2 H -2.15 -.25
(ev e).15 H(ral dif).25 E(ferent IPs that the connection might ha)-.25 E
.3 -.15(ve c)-.2 H(ome in on.).15 E F1(use Socket;)152 454.8 Q
($mysockaddr = getsockname\(SOCK\);)152 466.8 Q
(\($port, $myaddr\) = sockaddr_in\($mysockaddr\);)152 478.8 Q
(printf "Connect to %s [%s]\\n",)152 490.8 Q
(scalar gethostbyaddr\($myaddr, AF_INET\),)170 502.8 Q
(inet_ntoa\($myaddr\);)170 514.8 Q F0(getsock)108 531.6 Q(opt)-.1 E F2
(SOCKET)2.5 E F0(,LEVEL,OPTN)A(AME)-.35 E .004(Queries the option named)
128 543.6 R F2(OPTN)2.505 E(AME)-.315 E F0 .005(associated with)2.505 F
F2(SOCKET)2.505 E F0 .005(at a gi)2.505 F -.15(ve)-.25 G(n).15 E F2
(LEVEL)2.505 E F0 5.005(.O)C .005(ptions may e)-5.005 F .005(xist at)
-.15 F 2.95(multiple protocol le)128 555.6 R -.15(ve)-.25 G 2.95
(ls depending on the sock).15 F 2.949(et type, b)-.1 F 2.949
(ut at least the uppermost sock)-.2 F 2.949(et le)-.1 F -.15(ve)-.25 G
(l).15 E F2(SOL_SOCKET)128 567.6 Q F0 2.185(\(de\214ned in the)4.685 F
F1(Socket)4.685 E F0 2.185(module\) will e)4.685 F 2.186(xist. T)-.15 F
4.686(oq)-.8 G 2.186(uery options at another le)-4.686 F -.15(ve)-.25 G
4.686(lt).15 G(he)-4.686 E .127(protocol number of the appropriate prot\
ocol controlling the option should be supplied. F)128 579.6 R .127(or e)
-.15 F .127(xample, to)-.15 F .807
(indicate that an option is to be interpreted by the)128 591.6 R F2(TCP)
3.307 E F0(protocol,)3.307 E F2(LEVEL)3.307 E F0 .808
(should be set to the protocol)3.307 F(number of)128 603.6 Q F2(TCP)2.5
E F0 2.5(,w)C(hich you can get using)-2.5 E F1(getprotobyname)2.5 E F0
(.)A .086(The function returns a pack)128 621.6 R .086
(ed string representing the requested sock)-.1 F .086(et option, or)-.1
F F1(undef)2.586 E F0 .086(on error)2.586 F 2.586(,w)-.4 G(ith)-2.586 E
2.145(the reason for the error placed in)128 633.6 R F1($!)4.645 E F0
4.645(.J)C 2.145(ust what is in the pack)-4.645 F 2.146
(ed string depends on)-.1 F F2(LEVEL)4.646 E F0(and)4.646 E F2(OPTN)128
645.6 Q(AME)-.315 E F0 2.61(;c)C(onsult)-2.61 E F3 -.1(ge)2.61 G(tsoc).1
E -.1(ko)-.2 G(pt).1 E F0 .11(\(2\) for details.)1.666 F 2.61(Ac)5.11 G
.109(ommon case is that the option is an inte)-2.61 F(ger)-.15 E 2.609
(,i)-.4 G 2.609(nw)-2.609 G(hich)-2.609 E(case the result is a pack)128
657.6 Q(ed inte)-.1 E(ger)-.15 E 2.5(,w)-.4 G(hich you can decode using)
-2.5 E F1(unpack)2.5 E F0(with the)2.5 E F1(i)2.5 E F0(\(or)2.5 E F1(I)
2.5 E F0 2.5(\)f)C(ormat.)-2.5 E(Here')128 675.6 Q 2.5(sa)-.55 G 2.5(ne)
-2.5 G(xample to test whether Nagle')-2.65 E 2.5(sa)-.55 G
(lgorithm is enabled on a sock)-2.5 E(et:)-.1 E F1
(use Socket qw\(:all\);)152 693.6 Q
(defined\(my $tcp = getprotobyname\("tcp"\)\))152 717.6 Q
(or die "Could not determine the protocol number for tcp";)176 729.6 Q
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
(uted Perl Documentation)-.2 E(PERLFUNC\(1\))95.355 E/F1 10/Courier@0 SF
6(#m)152 84 S 6(y$)-6 G(tcp = IPPROTO_TCP; # Alternative)-6 E
(my $packed = getsockopt\($socket, $tcp, TCP_NODELAY\))152 96 Q
(or die "getsockopt TCP_NODELAY: $!";)176 108 Q
(my $nodelay = unpack\("I", $packed\);)152 120 Q(print "Nagle\010s algo\
rithm is turned ", $nodelay ? "off\\n" : "on\\n";)152 132 Q F0(gi)108
148.8 Q -.15(ve)-.25 G(n).15 E/F2 9/Times-Roman@0 SF .25(EXPR BLOCK)2.5
F F0(gi)108 160.8 Q -.15(ve)-.25 G(n).15 E F2(BLOCK)2.5 E F1(given)128
172.8 Q F0 .01(is analogous to the)2.51 F F1(switch)2.51 E F0 -.1(ke)
2.51 G(yw)-.05 E .01(ord in other languages.)-.1 F F1(given)2.51 E F0
(and)2.51 E F1(when)2.51 E F0 .01(are used in Perl to)2.51 F(implement)
128 184.8 Q F1(switch)2.5 E F0(/)A F1(case)A F0(lik)2.5 E 2.5(es)-.1 G
2.5(tatements. Only)-2.5 F -.2(av)2.5 G(ailable after Perl 5.10.)-.05 E
-.15(Fo)5 G 2.5(re).15 G(xample:)-2.65 E F1(use v5.10;)152 202.8 Q
(given \($fruit\) {)152 214.8 Q(when \(/apples?/\) {)176 226.8 Q
(print "I like apples.")200 238.8 Q(})176 250.8 Q(when \(/oranges?/\) {)
176 262.8 Q(print "I don\010t like oranges.")200 274.8 Q(})176 286.8 Q
(default {)176 298.8 Q(print "I don\010t like anything")200 310.8 Q(})
176 322.8 Q(})152 334.8 Q F0(See `)128 352.8 Q(`Switch statements')-.74
E 2.5('i)-.74 G 2.5(np)-2.5 G(erlsyn for detailed information.)-2.5 E
(glob)108 369.6 Q F2(EXPR)2.5 E F0(glob)108 381.6 Q .24(In list conte)
128 393.6 R .239(xt, returns a \(possibly empty\) list of \214lename e)
-.15 F .239(xpansions on the v)-.15 F .239(alue of)-.25 F F2(EXPR)2.739
E F0 .239(such as the)2.739 F 3.36(standard Unix shell)128 405.6 R/F3 10
/Times-Italic@0 SF(/bin/csh)5.86 E F0 -.1(wo)5.86 G 3.36
(uld do. In scalar conte).1 F 3.36
(xt, glob iterates through such \214lename)-.15 F -.15(ex)128 417.6 S
.524(pansions, returning undef when the list is e).15 F .523
(xhausted. This is the internal function implementing the)-.15 F F1
(<*.c>)128 429.6 Q F0(operator)3.16 E 3.16(,b)-.4 G .661
(ut you can use it directly)-3.36 F 3.161(.I)-.65 G(f)-3.161 E F2(EXPR)
3.161 E F0 .661(is omitted,)3.161 F F1($_)3.161 E F0 .661(is used.)3.161
F(The)5.661 E F1(<*.c>)3.161 E F0 .661(operator is)3.161 F
(discussed in more detail in `)128 441.6 Q(`I/O Operators')-.74 E 2.5
('i)-.74 G 2.5(np)-2.5 G(erlop.)-2.5 E 1.134(Note that)128 459.6 R F1
(glob)3.634 E F0 1.134(splits its ar)3.634 F 1.134
(guments on whitespace and treats each se)-.18 F 1.134
(gment as separate pattern.)-.15 F(As)6.134 E(such,)128 471.6 Q F1 1.063
(glob\("*.c *.h"\))3.563 F F0 1.063(matches all \214les with a)3.563 F
F3(.c)3.564 E F0(or)3.564 E F3(.h)3.564 E F0 -.15(ex)3.564 G 3.564
(tension. The).15 F -.15(ex)3.564 G(pression).15 E F1(glob\(".*)3.564 E
(*"\))128 483.6 Q F0(matches all \214les in the current w)2.5 E
(orking directory)-.1 E(.)-.65 E .276
(If non-empty braces are the only wildcard characters used in the)128
501.6 R F1(glob)2.775 E F0 2.775(,n)C 2.775<6f8c>-2.775 G .275
(lenames are matched, b)-2.775 F(ut)-.2 E .297(potentially man)128 513.6
R 2.797(ys)-.15 G .297(trings are returned.)-2.797 F -.15(Fo)5.297 G
2.797(re).15 G .298
(xample, this produces nine strings, one for each pairing of)-2.947 F
(fruits and colors:)128 525.6 Q F1(@many =)152 543.6 Q
(glob "{apple,tomato,cherry}={green,yellow,red}";)12 E F0(Be)128 561.6 Q
.263
(ginning with v5.6.0, this operator is implemented using the standard)
-.15 F F1(File::Glob)2.762 E F0 -.15(ex)2.762 G 2.762(tension. See).15 F
(File::Glob for details, including)128 573.6 Q F1(bsd_glob)2.5 E F0
(which does not treat whitespace as a pattern separator)2.5 E(.)-.55 E
(gmtime)108 590.4 Q F2(EXPR)2.5 E F0(gmtime)108 602.4 Q -.8(Wo)128 614.4
S(rks just lik).8 E 2.5(el)-.1 G(ocaltime b)-2.5 E(ut the returned v)-.2
E(alues are localized for the standard Greenwich time zone.)-.25 E .593
(Note: When called in list conte)128 632.4 R(xt,)-.15 E F1($isdst)3.093
E F0 3.093(,t)C .593(he last v)-3.093 F .594
(alue returned by gmtime, is al)-.25 F -.1(wa)-.1 G(ys).1 E F1(0)3.094 E
F0 5.594(.T)C .594(here is)-5.594 F(no Daylight Sa)128 644.4 Q(ving T)
-.2 E(ime in)-.35 E F2(GMT)2.5 E F0(.)A(See `)128 662.4 Q(`gmtime')-.74
E 2.5('i)-.74 G 2.5(np)-2.5 G(erlport for portability concerns.)-2.5 E
(goto)108 679.2 Q F2(LABEL)2.5 E F0(goto)108 691.2 Q F2(EXPR)2.5 E F0
(goto &N)108 703.2 Q(AME)-.35 E(The)128 715.2 Q F1(goto\255LABEL)2.654 E
F0 .154(form \214nds the statement labeled with)2.654 F F2(LABEL)2.654 E
F0 .154(and resumes e)2.654 F -.15(xe)-.15 G .153(cution there. It can')
.15 F(t)-.18 E .396(be used to get out of a block or subroutine gi)128
727.2 R -.15(ve)-.25 G 2.897(nt).15 G(o)-2.897 E F1(sort)2.897 E F0
5.397(.I)C 2.897(tc)-5.397 G .397(an be used to go almost an)-2.897 F
.397(ywhere else)-.15 F(perl v5.14.2)72 768 Q 198.17(2011-10-01 31)
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
(uted Perl Documentation)-.2 E(PERLFUNC\(1\))95.355 E 2.018
(within the dynamic scope, including out of subroutines, b)128 84 R
2.018(ut it')-.2 F 4.518(su)-.55 G 2.018
(sually better to use some other)-4.518 F .545(construct such as)128 96
R/F1 10/Courier@0 SF(last)3.045 E F0(or)3.045 E F1(die)3.045 E F0 5.545
(.T)C .545(he author of Perl has ne)-5.545 F -.15(ve)-.25 G 3.046(rf).15
G .546(elt the need to use this form of)-3.046 F F1(goto)3.046 E F0 .559
(\(in Perl, that is; C is another matter\).)128 108 R .559(\(The dif)
5.559 F .559(ference is that C does not of)-.25 F .558
(fer named loops combined)-.25 F(with loop control.)128 120 Q
(Perl does, and this replaces most structured uses of)5 E F1(goto)2.5 E
F0(in other languages.\))2.5 E(The)128 138 Q F1(goto\255EXPR)2.903 E F0
.403(form e)2.903 F .404
(xpects a label name, whose scope will be resolv)-.15 F .404
(ed dynamically)-.15 F 5.404(.T)-.65 G .404(his allo)-5.404 F(ws)-.25 E
2.359(for computed)128 150 R F1(goto)4.859 E F0 4.859(sp)C(er)-4.859 E
/F2 9/Times-Roman@0 SF(FOR)4.859 E(TRAN)-.54 E F0 4.859(,b)C 2.359
(ut isn')-5.059 F 4.859(tn)-.18 G 2.359(ecessarily recommended if you')
-4.859 F 2.359(re optimizing for)-.5 F(maintainability:)128 162 Q F1
(goto \("FOO", "BAR", "GLARCH"\)[$i];)152 180 Q F0 1.015(As sho)128 198
R 1.016(wn in this e)-.25 F(xample,)-.15 E F1(goto\255EXPR)3.516 E F0
1.016(is e)3.516 F -.15(xe)-.15 G 1.016(mpt from the `).15 F 1.016
(`looks lik)-.74 F 3.516(eaf)-.1 G(unction')-3.516 E 3.516('r)-.74 G
1.016(ule. A pair of)-3.516 F 3.94(parentheses follo)128 210 R 3.94
(wing it does not \(necessarily\) delimit its ar)-.25 F(gument.)-.18 E
F1(goto\("NE"\)."XT")6.44 E F0(is)6.44 E(equi)128 222 Q -.25(va)-.25 G
(lent to).25 E F1(goto NEXT)2.5 E F0(.)A .075(Use of)128 240 R F1
(goto\255LABEL)2.575 E F0(or)2.575 E F1(goto\255EXPR)2.575 E F0 .075
(to jump into a construct is deprecated and will issue a w)2.575 F
(arning.)-.1 E(Ev)128 252 Q .315
(en then, it may not be used to go into an)-.15 F 2.815(yc)-.15 G .315
(onstruct that requires initialization, such as a subroutine)-2.815 F
(or a)128 264 Q F1(foreach)2.5 E F0 2.5(loop. It)2.5 F(also can')2.5 E
2.5(tb)-.18 G 2.5(eu)-2.5 G
(sed to go into a construct that is optimized a)-2.5 E -.1(wa)-.15 G
-.65(y.).1 G(The)128 282 Q F1(goto\255&NAME)2.746 E F0 .247
(form is quite dif)2.746 F .247(ferent from the other forms of)-.25 F F1
(goto)2.747 E F0 5.247(.I)C 2.747(nf)-5.247 G .247(act, it isn')-2.847 F
2.747(tag)-.18 G .247(oto in the)-2.747 F 1.698
(normal sense at all, and doesn')128 294 R 4.198(th)-.18 G -2.25 -.2
(av e)-4.198 H 1.698(the stigma associated with other gotos.)4.398 F
1.698(Instead, it e)6.698 F 1.698(xits the)-.15 F 1.24
(current subroutine \(losing an)128 306 R 3.74(yc)-.15 G 1.24
(hanges set by)-3.74 F/F3 10/Times-Italic@0 SF(local\(\))3.74 E F0 3.74
(\)a)C 1.24(nd immediately calls in its place the named)-3.74 F .941
(subroutine using the current v)128 318 R .941(alue of)-.25 F F1(@_)
3.441 E F0 5.941(.T)C .941(his is used by)-5.941 F F1(AUTOLOAD)3.44 E F0
.94(subroutines that wish to load)3.44 F .313(another subroutine and th\
en pretend that the other subroutine had been called in the \214rst pla\
ce \(e)128 330 R(xcept)-.15 E .777(that an)128 342 R 3.277(ym)-.15 G
.777(odi\214cations to)-3.277 F F1(@_)3.277 E F0 .777
(in the current subroutine are propag)3.277 F .776
(ated to the other subroutine.\))-.05 F(After)5.776 E(the)128 354 Q F1
(goto)2.5 E F0 2.5(,n)C(ot e)-2.5 E -.15(ve)-.25 G(n).15 E F1(caller)2.5
E F0(will be able to tell that this routine w)2.5 E(as called \214rst.)
-.1 E F2 -.315(NA)128 372 S(ME).315 E F0(needn')2.674 E 2.674(tb)-.18 G
2.674(et)-2.674 G .175(he name of a subroutine; it can be a scalar v)
-2.674 F .175(ariable containing a code reference or a)-.25 F
(block that e)128 384 Q -.25(va)-.25 G(luates to a code reference.).25 E
(grep)108 400.8 Q F2 .25(BLOCK LIST)2.5 F F0(grep)108 412.8 Q F2(EXPR)
2.5 E F0(,LIST)A .322(This is similar in spirit to, b)128 424.8 R .322
(ut not the same as,)-.2 F F3(gr)2.822 E(ep)-.37 E F0 .322
(\(1\) and its relati)1.666 F -.15(ve)-.25 G 2.821(s. In).15 F
(particular)2.821 E 2.821(,i)-.4 G 2.821(ti)-2.821 G 2.821(sn)-2.821 G
.321(ot limited)-2.821 F(to using re)128 436.8 Q(gular e)-.15 E
(xpressions.)-.15 E(Ev)128 454.8 Q 1.599(aluates the)-.25 F F2(BLOCK)
4.099 E F0(or)4.099 E F2(EXPR)4.099 E F0 1.6(for each element of)4.1 F
F2(LIST)4.1 E F0 1.6(\(locally setting)4.1 F F1($_)4.1 E F0 1.6
(to each element\) and)4.1 F .255(returns the list v)128 466.8 R .255
(alue consisting of those elements for which the e)-.25 F .255
(xpression e)-.15 F -.25(va)-.25 G .255(luated to true.).25 F .255
(In scalar)5.255 F(conte)128 478.8 Q
(xt, returns the number of times the e)-.15 E(xpression w)-.15 E
(as true.)-.1 E F1(@foo = grep\(!/^#/, @bar\);)152 496.8 Q 6(#w)24 G
(eed out comments)-6 E F0(or equi)128 514.8 Q -.25(va)-.25 G(lently).25
E(,)-.65 E F1(@foo = grep {!/^#/} @bar;)152 532.8 Q 6(#w)24 G
(eed out comments)-6 E F0 .475(Note that)128 550.8 R F1($_)2.975 E F0
.475(is an alias to the list v)2.975 F .475
(alue, so it can be used to modify the elements of the)-.25 F F2(LIST)
2.975 E F0 5.476(.W)C(hile)-5.476 E 1.617(this is useful and supported,\
 it can cause bizarre results if the elements of)128 562.8 R F2(LIST)
4.117 E F0 1.617(are not v)4.117 F(ariables.)-.25 E(Similarly)128 574.8
Q 2.991(,g)-.65 G .492
(rep returns aliases into the original list, much as a for loop')-2.991
F 2.992(si)-.55 G(nde)-2.992 E 2.992(xv)-.15 G .492
(ariable aliases the list)-3.242 F 2.892(elements. That)128 586.8 R .391
(is, modifying an element of a list returned by grep \(for e)2.892 F
.391(xample, in a)-.15 F F1(foreach)2.891 E F0(,)A F1(map)2.891 E F0
.986(or another)128 598.8 R F1(grep)3.486 E F0 3.487(\)a)C .987
(ctually modi\214es the element in the original list.)-3.487 F .987
(This is usually something to be)5.987 F -.2(avo)128 610.8 S
(ided when writing clear code.).2 E(If)128 628.8 Q F1($_)2.698 E F0 .198
(is le)2.698 F .198(xical in the scope where the)-.15 F F1(grep)2.697 E
F0 .197(appears \(because it has been declared with)2.697 F F1 .197
(my $_)2.697 F F0 2.697(\)t)C(hen,)-2.697 E .354
(in addition to being locally aliased to the list elements,)128 640.8 R
F1($_)2.854 E F0 -.1(ke)2.855 G .355(eps being le).1 F .355
(xical inside the block; i.e., it)-.15 F(can')128 652.8 Q 2.5(tb)-.18 G
2.5(es)-2.5 G(een from the outside, a)-2.5 E -.2(vo)-.2 G(iding an).2 E
2.5(yp)-.15 G(otential side-ef)-2.5 E(fects.)-.25 E(See also `)128 670.8
Q(`map')-.74 E 2.5('f)-.74 G(or a list composed of the results of the)
-2.5 E F2(BLOCK)2.5 E F0(or)2.5 E F2(EXPR)2.5 E F0(.)A(he)108 687.6 Q(x)
-.15 E F2(EXPR)2.5 E F0(he)108 699.6 Q(x)-.15 E(Interprets)128 699.6 Q
F2(EXPR)3.647 E F0 1.147(as a he)3.647 F 3.647(xs)-.15 G 1.146
(tring and returns the corresponding v)-3.647 F 3.646(alue. \(T)-.25 F
3.646(oc)-.8 G(on)-3.646 E -.15(ve)-.4 G 1.146(rt strings that might).15
F(start with either)128 711.6 Q F1(0)2.5 E F0(,)A F1(0x)2.5 E F0 2.5(,o)
C(r)-2.5 E F1(0b)2.5 E F0 2.5(,s)C(ee `)-2.5 E(`oct')-.74 E 2.5('.\) If)
-.74 F F2(EXPR)2.5 E F0(is omitted, uses)2.5 E F1($_)2.5 E F0(.)A
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
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(print hex \0100xAf\010; # prints \010175\010)152 84 Q
(print hex \010aF\010;)152 96 Q 6(#s)18 G(ame)-6 E F0(He)128 114 Q 2.951
(xs)-.15 G .451(trings may only represent inte)-2.951 F 2.951
(gers. Strings)-.15 F .451(that w)2.951 F .452(ould cause inte)-.1 F
.452(ger o)-.15 F -.15(ve)-.15 G(r\215o).15 E 2.952(wt)-.25 G .452
(rigger a w)-2.952 F(arning.)-.1 E 1.637
(Leading whitespace is not stripped, unlik)128 126 R(e)-.1 E/F2 10
/Times-Italic@0 SF(oct\(\))4.137 E F0 4.137(.T)C 4.137(op)-4.937 G 1.637
(resent something as he)-4.137 F 1.637(x, look into `)-.15 F -1.95
(`printf ')-.74 F(',)-.74 E -.74(``)128 138 S -1.95(sprintf ').74 F
(', and `)-.74 E(`unpack')-.74 E('.)-.74 E(import)108 154.8 Q/F3 9
/Times-Roman@0 SF(LIST)2.5 E F0 .323(There is no b)128 166.8 R(uiltin)
-.2 E F1(import)2.823 E F0 2.823(function. It)2.823 F .324
(is just an ordinary method \(subroutine\) de\214ned \(or inherited\))
2.823 F 2.12(by modules that wish to e)128 178.8 R 2.119
(xport names to another module.)-.15 F(The)7.119 E F1(use)4.619 E F0
2.119(function calls the)4.619 F F1(import)4.619 E F0
(method for the package used.)128 190.8 Q(See also `)5 E(`use')-.74 E
(', perlmod, and Exporter)-.74 E(.)-.55 E(inde)108 207.6 Q(x)-.15 E F3
(STR)2.5 E F0(,SUBSTR,POSITION)A(inde)108 219.6 Q(x)-.15 E F3(STR)2.5 E
F0(,SUBSTR)A .467(The inde)128 231.6 R 2.967(xf)-.15 G .467
(unction searches for one string within another)-2.967 F 2.967(,b)-.4 G
.468(ut without the wildcard-lik)-3.167 F 2.968(eb)-.1 G(eha)-2.968 E
.468(vior of a)-.2 F .304(full re)128 243.6 R(gular)-.15 E(-e)-.2 E .304
(xpression pattern match.)-.15 F .304
(It returns the position of the \214rst occurrence of)5.304 F F3(SUBSTR)
2.803 E F0(in)2.803 E F3(STR)2.803 E F0 2.032(at or after)128 255.6 R F3
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(before the be)2.68 F .18
(ginning of the string or after its end is treated as if it were the be)
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E F1(int\(\2556.725/0.025\))128 368.4 Q F0 .871
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128 493.2 Q F0 .811(will be read and/or written depending on the)3.311 F
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176 589.2 R(value)6 E 84(0s)182 601.2 S(tring "0 but true")-84 E
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F 1.343(ailure, yet you can still easily determine the actual)-.1 F -.25
(va)128 643.2 S(lue returned by the operating system:).25 E F1
($retval = ioctl\(...\) || \2551;)152 661.2 Q
(printf "System returned %d\\n", $retval;)152 673.2 Q F0 3.284
(The special string)128 691.2 R F1 3.284("0 but true")5.784 F F0 3.284
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388.8 Q F0(or ho)128 406.8 Q 2.5(wa)-.25 G(bout sorted by k)-2.5 E -.15
(ey)-.1 G(:).15 E F2(foreach $key \(sort\(keys %ENV\)\) {)152 424.8 Q
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(foreach $key \(sort { $hash{$b} <=> $hash{$a} } keys %hash\) {)152
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(keys @array)2.5 E F0(in an lv)2.5 E(alue conte)-.25 E
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142.8 R .406
(Returns the number of processes successfully signaled \(which is)5.406
F(not necessarily the same as the number actually killed\).)128 154.8 Q
F1($cnt = kill 1, $child1, $child2;)152 172.8 Q(kill 9, @goners;)152
184.8 Q F0(If)128 202.8 Q F2(SIGN)3.45 E(AL)-.315 E F0 .95
(is zero, no signal is sent to the process, b)3.45 F(ut)-.2 E F1(kill)
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(usually w)128 268.8 Q(ant to use positi)-.1 E .3 -.15(ve n)-.25 H
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(If the)6.943 F F2(LABEL)4.443 E F0 1.943
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(xit a block that returns a v)-.15 F .273(alue such as)-.25 F F1 .273
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(Note that a block by itself is semantically identical to a loop that e)
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F F2(EXPR)3.422 E F0 5.922(.T)C .922
(his is the internal function implementing the)-5.922 F F1(\\L)3.423 E
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572.4 Q F2(EXPR)2.5 E F0(is omitted, uses)2.5 E F1($_)2.5 E F0(.)A
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F1
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(ymous hashes each with only one entry apiece.)-.15 E(mkdir)108 334.8 Q
F2(FILEN)2.5 E(AME)-.315 E F0(,MASK)A(mkdir)108 346.8 Q F2(FILEN)2.5 E
(AME)-.315 E F0(mkdir)108 358.8 Q 1.048
(Creates the directory speci\214ed by)128 370.8 R F2(FILEN)3.548 E(AME)
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(MASK)3.549 E F0 1.049(\(as modi\214ed by)3.549 F F1(umask)128 382.8 Q
F0 2.572(\). If)B .072
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412.8 R -.15(ve)-.25 G F2(MASK)3.302 E F0 .652
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3.15 E F0 .65(than it is to supply a restricti)3.15 F -.15(ve)-.25 G F2
(MASK)3.299 E F0 .649(and gi)3.149 F .949 -.15(ve t)-.25 H .649
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(use IPC::SysV;)152 555.6 Q F0 .739
(\214rst to get the correct constant de\214nitions.)128 573.6 R(If)5.739
E F2(CMD)3.239 E F0(is)3.239 E F1(IPC_STAT)3.239 E F0 3.239(,t)C(hen)
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638.4 R F2(IPC)3.171 E F0(function)3.171 E F3(msg)3.171 E -.1(ge)-.1 G
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679.2 R F2(IPC)3.562 E F0 1.062(function msgrcv to recei)3.562 F 1.362
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(open\(my $fh, "<", "input.txt"\))152 250.8 Q
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5.231 G 2.731(uc)1.1 G -.834(an \212 b)-2.731 F .231(ut shouldn')-.2 F
1.666(t\212o)-.18 G .231(mit the mode in these forms)-1.666 F .011
(when that mode is)128 628.8 R F2(<)2.511 E F0 5.011(.I)C 2.511(ti)
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(if the \214lename ar)2.512 F(gument)-.18 E(is a kno)128 640.8 Q
(wn literal.)-.25 E -.15(Fo)128 658.8 S 2.639(rt).15 G .139
(hree or more ar)-2.639 F .139(guments if)-.18 F F3(MODE)2.639 E F0(is)
2.639 E F2<7cad>2.639 E F0 2.639(,t)C .138
(he \214lename is interpreted as a command to which output)-2.639 F .102
(is to be piped, and if)128 670.8 R F3(MODE)2.602 E F0(is)2.602 E F2
<ad7c>2.602 E F0 2.602(,t)C .102
(he \214lename is interpreted as a command that pipes output to us.)
-2.602 F(In)5.103 E 1.786(the tw)128 682.8 R(o-ar)-.1 E 1.786
(gument \(and one-ar)-.18 F 1.785
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1.785(ith the command.)-4.285 F(See)6.785 E -.74(``)128 694.8 S(Using)
.74 E F1(open\(\))3.972 E F0(for)3.972 E F3(IPC)3.972 E F0 2.952 -.74
('' i)D 3.972(np).74 G 1.472(erlipc for more e)-3.972 F 1.472
(xamples of this.)-.15 F(\(Y)6.472 E 1.472(ou are not allo)-1.1 F 1.472
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(command that pipes both in)128 706.8 R F1(and)6.843 E F0 4.343(out, b)
6.843 F 4.343(ut see IPC::Open2, IPC::Open3, and `)-.2 F(`Bidirectional)
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(gument \(and one-ar)-.18 F .624(gument\) form, opening)-.18 F F2<3cad>
3.124 E F0(or)3.124 E F2<ad>3.124 E F0(opens)3.124 E F1(STDIN)3.124 E F0
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150 Q F0(.)A -1.1(Yo)128 168 S 3.223(um)1.1 G .723
(ay \(and usually should\) use the three-ar)-3.223 F .724
(gument form of open to specify I/O layers \(sometimes)-.18 F .485
(referred to as `)128 180 R(`disciplines')-.74 E .485
('\) to apply to the handle that af)-.74 F .485(fect ho)-.25 F 2.985(wt)
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(\(see open and PerlIO for more details\). F)128 192 Q(or e)-.15 E
(xample:)-.15 E F2(open\(my $fh, "<:encoding\(UTF\2558\)", "filename"\))
140 210 Q(|| die "can\010t open UTF\2558 encoded filename: $!";)152 222
Q F0 .752(opens the UTF8\255encoded \214le containing Unicode character\
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(speci\214ed in the three-ar)128 252 R .473(gument form, then def)-.18 F
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(ar; usually set)-.25 F(by the)128 264 Q/F3 10/Times-Bold@0 SF(open)2.5
E F0(pragma or the switch)2.5 E F3(\255CioD)2.5 E F0 2.5(\)a)C
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(Open returns nonzero on success, the unde\214ned v)128 282 R 1.327
(alue otherwise.)-.25 F 1.327(If the)6.327 F F2(open)3.828 E F0(in)3.828
E -.2(vo)-.4 G(lv).2 E 1.328(ed a pipe, the)-.15 F(return v)128 294 Q
(alue happens to be the pid of the subprocess.)-.25 E 1.679(If you')128
312 R 1.678(re running Perl on a system that distinguishes between te)
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(or tips for dealing with this.)-3.066 F .566(The k)5.566 F .866 -.15
(ey d)-.1 H .566(istinction between systems that).15 F(need)128 336 Q F2
(binmode)2.735 E F0 .235(and those that don')2.735 F 2.735(ti)-.18 G
2.735(st)-2.735 G .235(heir te)-2.735 F .235(xt \214le formats.)-.15 F
.235(Systems lik)5.235 F 2.735(eU)-.1 G .235(nix, Mac)-2.735 F F1(OS)
2.735 E F0 2.735(,a)C .234(nd Plan 9,)-2.735 F .477(that end lines with\
 a single character and encode that character in C as)128 348 R F2
("\\n")2.977 E F0 .477(do not need)2.977 F F2(binmode)2.977 E F0(.)A
(The rest need it.)128 360 Q .762(When opening a \214le, it')128 378 R
3.261(ss)-.55 G .761(eldom a good idea to continue if the request f)
-3.261 F .761(ailed, so)-.1 F F2(open)3.261 E F0 .761(is frequently)
3.261 F .021(used with)128 390 R F2(die)2.521 E F0 5.021(.E)C -.15(ve)
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(ant \(say)-.1 F 2.522(,i)-.65 G 2.522(na)-2.522 G F1(CGI)A F0 .022
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(suitable error message \(b)128 402 R 1.74
(ut there are modules that can help with that problem\)\) al)-.2 F -.1
(wa)-.1 G 1.74(ys check the).1 F(return v)128 414 Q
(alue from opening a \214le.)-.25 E 2.07(As a special case the three-ar)
128 432 R 2.071(gument form with a read/write mode and the third ar)-.18
F 2.071(gument being)-.18 F F2(undef)128 444 Q F0(:)A F2
(open\(my $tmp, "+>", undef\) or die ...)152 462 Q F0 .123
(opens a \214lehandle to an anon)128 480 R .123(ymous temporary \214le.)
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492 R -1.1(Yo)7.14 G 4.64(uw)1.1 G 2.14(ill need to)-4.64 F/F4 10
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504 Q .147(Since v5.8.0, Perl has b)128 522 R .147
(uilt using PerlIO by def)-.2 F 2.647(ault. Unless)-.1 F(you')2.647 E
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(uilding Perl)-.2 F(with)128 534 Q F2(Configure \255Uuseperlio)2.5 E F0
(\), you can open \214lehandles directly to Perl scalars via:)A F2
(open\($fh, ">", \\$variable\) || ..)152 552 Q F0 1.6 -.8(To \()128 570
T(re\)open).8 E F2(STDOUT)2.5 E F0(or)2.5 E F2(STDERR)2.5 E F0
(as an in-memory \214le, close it \214rst:)2.5 E F2(close STDOUT;)152
588 Q(open\(STDOUT, ">", \\$variable\))152 600 Q
(or die "Can\010t open STDOUT: $!";)176 612 Q F0(General e)128 630 Q
(xamples:)-.15 E F2($ARTICLE = 100;)152 648 Q
(open\(ARTICLE\) or die "Can\010t find article $ARTICLE: $!\\n";)152 660
Q(while \(<ARTICLE>\) {...)152 672 Q
(open\(LOG, ">>/usr/spool/news/twitlog"\);)152 696 Q 6(#\()12 G
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(open\(ARTICLE, "caesar <$article |"\))152 192 Q 6(#d)36 G(itto)-6 E
(or die "Can\010t start caesar: $!";)176 204 Q
(open\(EXTRACT, "|sort >Tmp$$"\))152 228 Q 6(#$)72 G 6($i)-6 G 6(so)-6 G
(ur process id)-6 E(or die "Can\010t start sort: $!";)176 240 Q 6(#i)152
264 S(n\255memory files)-6 E(open\(MEMORY, ">", \\$var\))152 276 Q
(or die "Can\010t open memory file: $!";)176 288 Q
(print MEMORY "foo!\\n";)152 300 Q 6(#o)114 G(utput will appear in $var)
-6 E 6(#p)152 324 S
(rocess argument list of files along with any includes)-6 E
(foreach $file \(@ARGV\) {)152 348 Q(process\($file, "fh00"\);)176 360 Q
(})152 372 Q(sub process {)152 396 Q(my\($filename, $input\) = @_;)176
408 Q 18($input++; #)176 420 R(this is a string increment)6 E
(unless \(open\($input, "<", $filename\)\) {)176 432 Q
(print STDERR "Can\010t open $filename: $!\\n";)200 444 Q(return;)200
456 Q(})176 468 Q(local $_;)176 492 Q(while \(<$input>\) {)176 504 Q 6
(#n)24 G(ote use of indirection)-6 E(if \(/^#include "\(.*\)"/\) {)200
516 Q(process\($1, $input\);)224 528 Q(next;)224 540 Q(})200 552 Q 54
(#... #)200 564 R(whatever)6 E(})176 576 Q(})152 588 Q F0
(See perliol for detailed info on PerlIO.)128 606 Q -1.1(Yo)128 624 S
2.543(um)1.1 G .043(ay also, in the Bourne shell tradition, specify an)
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128 648 Q F0 4.098(\)a)C 1.598(nd opened.)-4.098 F -1.1(Yo)6.598 G 4.098
(um)1.1 G 1.598(ay use)-4.098 F F1(&)4.098 E F0(after)4.098 E F1(>)4.098
E F0(,)A F1(>>)4.098 E F0(,)A F1(<)4.098 E F0(,)A F1(+>)4.098 E F0(,)A
F1(+>>)4.098 E F0 4.099(,a)C(nd)-4.099 E F1(+<)4.099 E F0 6.599(.T)C
1.599(he mode you specify)-6.599 F .283
(should match the mode of the original \214lehandle.)128 660 R .282
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30 E(select STDERR; $| = 1;)152 168 Q 6(#m)12 G(ake unbuffered)-6 E
(select STDOUT; $| = 1;)152 180 Q 6(#m)12 G(ake unbuffered)-6 E
(print STDOUT "stdout 1\\n";)152 204 Q 6(#t)12 G(his works for)-6 E
(print STDERR "stderr 1\\n";)152 216 Q 6(#s)12 G(ubprocesses too)-6 E
(open\(STDOUT, ">&", $oldout\) or die "Can\010t dup \\$oldout: $!";)152
240 Q(open\(STDERR, ">&OLDERR"\))152 252 Q
(or die "Can\010t dup OLDERR: $!";)24 E(print STDOUT "stdout 2\\n";)152
276 Q(print STDERR "stderr 2\\n";)152 288 Q F0 1.67(If you specify)128
306 R F1(\010<&=X\010)4.17 E F0 4.17(,w)C(here)-4.17 E F1(X)4.17 E F0
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(is a \214le descriptor number or a \214lehandle, then Perl will do an)
4.17 F(equi)128 318 Q -.25(va)-.25 G .38(lent of C').25 F(s)-.55 E F1
(fdopen)2.88 E F0 .38(of that \214le descriptor \(and not call)2.88 F F1
(dup\(2\))2.88 E F0 .38(\); this is more parsimonious of)B
(\214le descriptors.)128 330 Q -.15(Fo)5 G 2.5(re).15 G(xample:)-2.65 E
F1 6(#o)152 348 S(pen for input, reusing the fileno of $fd)-6 E
(open\(FILEHANDLE, "<&=$fd"\))152 360 Q F0(or)128 378 Q F1
(open\(FILEHANDLE, "<&=", $fd\))152 396 Q F0(or)128 414 Q F1 6(#o)152
432 S(pen for append, using the fileno of OLDFH)-6 E
(open\(FH, ">>&=", OLDFH\))152 444 Q F0(or)128 462 Q F1
(open\(FH, ">>&=OLDFH"\))152 480 Q F0 2.034(Being parsimonious on \214l\
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2.034(xample when)-.15 F 1.832
(something is dependent on \214le descriptors, lik)128 510 R 4.333(ef)
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2.862(,t)C .363(he \214lehandles will share)-2.862 F
(the same underlying system \214le descriptor)128 546 Q(.)-.55 E .388(N\
ote that under Perls older than 5.8.0, Perl uses the standard C library\
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(alue,)-.25 E(typically 255.)128 588 Q -.15(Fo)5 G 2.5(rP).15 G
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1.915(and looking for the)4.415 F F1(useperlio=)128 618 Q F0 2.5
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(t.)-.18 E .293(If you open a pipe on the command)128 636 R F1<ad>2.793
E F0 .294(\(that is, specify either)2.793 F F1<7cad>2.794 E F0(or)2.794
E F1<ad7c>2.794 E F0 .294(with the one\255 or tw)2.794 F(o-ar)-.1 E
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2.873 E F0 .373(returns twice: in the parent process it returns the)
2.873 F .735(pid of the child process, and in the child process it retu\
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(to determine whether the open w)2.5 E(as successful.)-.1 E -.15(Fo)128
690 S 2.5(re).15 G(xample, use either)-2.65 E F1
($child_pid = open\(FROM_KID, "|\255"\))152 708 Q
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(ither write TO_KID or else read FROM_KID)-6 E(...)176 156 Q
(wait $child_pid;)176 168 Q 6(}e)152 180 S(lse {)-6 E 6(#a)176 192 S 6
(mt)-6 G(he child; use STDIN/STDOUT normally)-6 E(...)176 204 Q(exit;)
176 216 Q(})152 228 Q F0 2.729(The \214lehandle beha)128 246 R -.15(ve)
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(ut I/O to that \214lehandle is piped from/to the)-.2 F F2(STDOUT/STDIN)
128 258 Q F0 .681(of the child process.)3.181 F .681
(In the child process, the \214lehandle isn')5.681 F 3.181(to)-.18 G
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282 S .08(rcise more control o).15 F -.15(ve)-.15 G 2.58(rj).15 G .08
(ust ho)-2.58 F 2.58(wt)-.25 G .08(he pipe command gets e)-2.58 F -.15
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294 Q 2.5(tw)-.18 G(ant to ha)-2.6 E .3 -.15(ve t)-.2 H 2.5(os).15 G
(can shell commands for metacharacters.)-2.5 E(The follo)128 312 Q
(wing blocks are more or less equi)-.25 E -.25(va)-.25 G(lent:).25 E F1
(open\(FOO, "|tr \010[a\255z]\010 \010[A\255Z]\010"\);)152 330 Q
(open\(FOO, "|\255", "tr \010[a\255z]\010 \010[A\255Z]\010"\);)152 342 Q
(open\(FOO, "|\255"\) || exec \010tr\010, \010[a\255z]\010, \010[A\255Z\
]\010;)152 354 Q
(open\(FOO, "|\255", "tr", \010[a\255z]\010, \010[A\255Z]\010\);)152 366
Q(open\(FOO, "cat \255n \010$file\010|"\);)152 390 Q
(open\(FOO, "\255|", "cat \255n \010$file\010"\);)152 402 Q
(open\(FOO, "\255|"\) || exec "cat", "\255n", $file;)152 414 Q
(open\(FOO, "\255|", "cat", "\255n", $file\);)152 426 Q F0 .739
(The last tw)128 444 R 3.239(oe)-.1 G .739(xamples in each block sho)
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(platforms. A)128 456 R .645
(good rule of thumb is that if your platform has a real)3.145 F F1
(fork\(\))3.145 E F0 .646(\(in other w)3.146 F .646(ords, if your)-.1 F
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(the list form of the pipe so you can pass literal ar)128 480 R .979
(guments to the command without risk of the shell)-.18 F 1.682
(interpreting an)128 492 R 4.182(ys)-.15 G 1.682
(hell metacharacters in them.)-4.182 F(Ho)6.682 E(we)-.25 E -.15(ve)-.25
G 2.481 -.4(r, t).15 H 1.681(his also bars you from opening pipes to).4
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504 Q F1(open\(FOO, "|cat \255n | expand \2554 | lpr"\))152 522 Q
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(may do a fork, b)128 582 R .614
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(OFLUSH in English\) or call the)-.18 F F1(autoflush\(\))3.157 E F0 .657
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(On systems that support a close-on-e)128 624 R -.15(xe)-.15 G 3.679
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(iped \214lehandle causes the parent process to w)-3.125 F .626
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(Use the three-ar)128 114 Q
(gument form to open a \214le with arbitrary weird characters in it,)
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(ork on some bizarre \214lesystems\).)-.1 F 1.597
(One should conscientiously choose between the)6.597 F/F2 10
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.255(will allo)128 270 R 2.755(wt)-.25 G .255(he user to specify an ar)
-2.755 F .255(gument of the form)-.18 F F1 .255("rsh cat file |")2.755 F
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(\214lename that happens to ha)128 282 Q .3 -.15(ve a t)-.2 H
(railing space, while).15 E F1(open\(IN, "<", $ARGV[0]\))152 300 Q
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(If you w)128 348 R 1.181(ant a `)-.1 F(`real')-.74 E 3.681('C)-.74 G F1
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(ay to protect your \214lenames from interpretation.)-.1 F -.15(Fo)5.144
G(r).15 E -.15(ex)128 384 S(ample:).15 E F1(use IO::Handle;)152 402 Q
(sysopen\(HANDLE, $path, O_RDWR|O_CREAT|O_EXCL\))152 414 Q
(or die "sysopen $path: $!";)176 426 Q
($oldfh = select\(HANDLE\); $| = 1; select\($oldfh\);)152 438 Q
(print HANDLE "stuff $$\\n";)152 450 Q(seek\(HANDLE, 0, 0\);)152 462 Q
(print "File contains: ", <HANDLE>;)152 474 Q F0 .628
(Using the constructor from the)128 492 R F1(IO::Handle)3.127 E F0 .627
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(ut silently\) close once their reference counts become zero, typically)
-.2 F(at scope e)128 528 Q(xit:)-.15 E F1(use IO::File;)152 546 Q(#...)
152 558 Q(sub read_myfile_munged {)152 570 Q(my $ALL = shift;)176 582 Q
6(#o)176 594 S 6(rj)-6 G(ust leave it undef to autoviv)-6 E
(my $handle = IO::File\255>new;)176 606 Q
(open\($handle, "<", "myfile"\) or die "myfile: $!";)176 618 Q
($first = <$handle>)176 630 Q(or return \(\);)200 642 Q 6(#A)30 G
(utomatically closed here.)-6 E(mung\($first\) or die "mung failed";)176
654 Q 6(#O)12 G 6(rh)-6 G(ere.)-6 E
(return \(first, <$handle>\) if $ALL;)176 666 Q 6(#O)12 G 6(rh)-6 G
(ere.)-6 E(return $first;)176 678 Q 6(#O)132 G 6(rh)-6 G(ere.)-6 E(})152
690 Q/F3 9/Times-Bold@0 SF -1.08(WA)128 708 S(RNING:)1.08 E F0 2.002
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(See `)128 132 Q(`seek')-.74 E 2.5('f)-.74 G
(or some details about mixing reading and writing.)-2.5 E(opendir)108
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172.8 Q F1(closedir)3.158 E F0 5.658(.R)C .658
(eturns true if successful.)-5.658 F F2(DIRHANDLE)5.657 E F0 .657
(may be an e)3.157 F .657(xpression whose v)-.15 F .657(alue can be)-.25
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128 184.8 R(If)5.602 E F2(DIRHANDLE)3.102 E F0 .603
(is an unde\214ned scalar)3.102 F -.25(va)128 196.8 S .102
(riable \(or array or hash element\), the v).25 F .102
(ariable is assigned a reference to a ne)-.25 F 2.601(wa)-.25 G(non)
-2.601 E .101(ymous dirhandle;)-.15 F(that is, it')128 208.8 Q 2.5(sa)
-.55 G(uto)-2.5 E(vi)-.15 E 2.5(vi\214ed. DIRHANDLEs)-.25 F(ha)2.5 E .3
-.15(ve t)-.2 H(heir o).15 E(wn namespace separate from FILEHANDLEs.)
-.25 E(See the e)128 226.8 Q(xample at)-.15 E F1(readdir)2.5 E F0(.)A
(ord)108 243.6 Q F2(EXPR)2.5 E F0(ord)108 255.6 Q .666
(Returns the numeric \(the nati)128 255.6 R .966 -.15(ve 8)-.25 H .666
(\255bit encoding, lik).15 F(e)-.1 E F2(ASCII)3.166 E F0(or)3.166 E F2
(EBCDIC)3.166 E F0 3.166(,o)C 3.166(rU)-3.166 G .666(nicode\) v)-3.166 F
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4.637 E F0 7.137(.I)C(f)-7.137 E F2(EXPR)4.637 E F0 2.136
(is an empty string, returns 0.)4.637 F(If)7.136 E F2(EXPR)4.636 E F0
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2.5(,n)C(ot byte.\))-2.5 E -.15(Fo)128 297.6 S 2.5(rt).15 G(he re)-2.5 E
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(perlunicode for more about Unicode.)2.5 E(our)108 314.4 Q F2(EXPR)2.5 E
F0(our)108 326.4 Q F2 .25(TYPE EXPR)2.5 F F0(our)108 338.4 Q F2(EXPR)2.5
E F0(:)2.5 E F2 -.999(AT)2.5 G(TRS).999 E F0(our)108 350.4 Q F2 .25
(TYPE EXPR)2.5 F F0(:)2.5 E F2 -.999(AT)2.5 G(TRS).999 E F1(our)128
362.4 Q F0 1.903(associates a simple name with a package v)4.403 F 1.903
(ariable in the current package for use within the)-.25 F .209
(current scope.)128 374.4 R(When)5.209 E F1 .209
(use strict \010vars\010)2.709 F F0 .209(is in ef)2.709 F(fect,)-.25 E
F1(our)2.709 E F0 .208(lets you use declared global v)2.709 F(ariables)
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128 386.4 R .428(xical scope of the)-.15 F F1(our)2.928 E F0 2.928
(declaration. In)2.928 F(this)2.928 E -.1(wa)128 398.4 S(y).1 E F1(our)
2.5 E F0(dif)2.5 E(fers from)-.25 E F1(use vars)2.5 E F0 2.5(,w)C
(hich is package-scoped.)-2.5 E(Unlik)128 416.4 Q(e)-.1 E F1(my)3.482 E
F0(or)3.482 E F1(state)3.482 E F0 3.482(,w)C .981
(hich allocates storage for a v)-3.482 F .981
(ariable and associates a simple name with that)-.25 F .585
(storage for use within the current scope,)128 428.4 R F1(our)3.086 E F0
.586(associates a simple name with a package \(read: global\))3.086 F
-.25(va)128 440.4 S .548
(riable in the current package, for use within the current le).25 F .548
(xical scope.)-.15 F .548(In other w)5.548 F(ords,)-.1 E F1(our)3.048 E
F0 .548(has the)3.048 F(same scoping rules as)128 452.4 Q F1(my)2.5 E F0
(or)2.5 E F1(state)2.5 E F0 2.5(,b)C(ut does not necessarily create a v)
-2.7 E(ariable.)-.25 E(If more than one v)128 470.4 Q
(alue is listed, the list must be placed in parentheses.)-.25 E F1
(our $foo;)152 488.4 Q(our\($bar, $baz\);)152 500.4 Q F0(An)128 518.4 Q
F1(our)3.065 E F0 .565(declaration declares a global v)3.065 F .566
(ariable that will be visible across its entire le)-.25 F .566
(xical scope, e)-.15 F -.15(ve)-.25 G(n).15 E .286
(across package boundaries.)128 530.4 R .286(The package in which the v)
5.286 F .285(ariable is entered is determined at the point of)-.25 F
(the declaration, not at the point of use.)128 542.4 Q
(This means the follo)5 E(wing beha)-.25 E(vior holds:)-.2 E F1
(package Foo;)152 560.4 Q(our $bar;)152 572.4 Q 6(#d)36 G
(eclares $Foo::bar for rest of lexical scope)-6 E($bar = 20;)152 584.4 Q
(package Bar;)152 608.4 Q(print $bar;)152 620.4 Q 6(#p)24 G
(rints 20, as it refers to $Foo::bar)-6 E F0(Multiple)128 638.4 Q F1
(our)3.67 E F0 1.17(declarations with the same name in the same le)3.67
F 1.171(xical scope are allo)-.15 F 1.171(wed if the)-.25 F 3.671(ya)
-.15 G 1.171(re in)-3.671 F(dif)128 650.4 Q 1.317(ferent packages.)-.25
F 1.317(If the)6.317 F 3.817(yh)-.15 G 1.316
(appen to be in the same package, Perl will emit w)-3.817 F 1.316
(arnings if you ha)-.1 F -.15(ve)-.2 G(ask)128 662.4 Q .908
(ed for them, just lik)-.1 F 3.408(em)-.1 G(ultiple)-3.408 E F1(my)3.408
E F0 3.408(declarations. Unlik)3.408 F 3.408(eas)-.1 G(econd)-3.408 E F1
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(the name to a fresh v)128 674.4 R 1.306(ariable, a second)-.25 F F1
(our)3.806 E F0 1.306
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(declaration may also ha)2.5 E .3 -.15(ve a l)-.2 H(ist of attrib).15 E
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(pragma, or starting)3.542 F .366(from Perl 5.8.0 also via the)128 264 R
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(alue looks lik)-.25 F(e)-.1 E .105(its machine-le)128 328.8 R -.15(ve)
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.104(xample, on 32\255bit machines an inte)-.15 F .104
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(See perlpacktut for an introduction to this function.)128 358.8 Q(The)
128 376.8 Q F2(TEMPLA)2.5 E(TE)-.999 E F0
(is a sequence of characters that gi)2.5 E .3 -.15(ve t)-.25 H
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(aA)152 394.8 S(string with arbitrary binary data, will be null padded.)
-6 E 12(AA)152 406.8 S(text \(ASCII\) string, will be space padded.)-6 E
12(ZA)152 418.8 S
(null\255terminated \(ASCIZ\) string, will be null padded.)-6 E 12(bA)
152 442.8 S
(bit string \(ascending bit order inside each byte, like vec\(\)\).)-6 E
12(BA)152 454.8 S(bit string \(descending bit order inside each byte\).)
-6 E 12(hA)152 466.8 S(hex string \(low nybble first\).)-6 E 12(HA)152
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(signed char \(8\255bit\) value.)-6 E 12(CA)152 514.8 S 6(nu)-12 G
(nsigned char \(octet\) value.)-6 E 12(WA)152 526.8 S 6(nu)-12 G
(nsigned char value \(can be greater than 255\).)-6 E 12(sA)152 550.8 S
(signed short \(16\255bit\) value.)-6 E 12(SA)152 562.8 S 6(nu)-12 G
(nsigned short value.)-6 E 12(lA)152 586.8 S
(signed long \(32\255bit\) value.)-6 E 12(LA)152 598.8 S 6(nu)-12 G
(nsigned long value.)-6 E 12(qA)152 622.8 S
(signed quad \(64\255bit\) value.)-6 E 12(QA)152 634.8 S 6(nu)-12 G
(nsigned quad value.)-6 E
(\(Quads are available only if your system supports 64\255bit)164 646.8
Q(integer values _and_ if Perl has been compiled to support those.)170
658.8 Q(Raises an exception otherwise.\))194 670.8 Q 12(iA)152 694.8 S
(signed integer value.)-6 E 12(IA)152 706.8 S(unsigned integer value.)-6
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(Its exact)12 E
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12(NA)152 108 S 6(nu)-12 G
(nsigned long \(32\255bit\) in "network" \(big\255endian\) order.)-6 E
12(vA)152 120 S 6(nu)-12 G
(nsigned short \(16\255bit\) in "VAX" \(little\255endian\) order.)-6 E
12(VA)152 132 S 6(nu)-12 G
(nsigned long \(32\255bit\) in "VAX" \(little\255endian\) order.)-6 E 18
(jA)152 156 S(Perl internal signed integer value \(IV\).)-12 E 18(JA)152
168 S(Perl internal unsigned integer value \(UV\).)-12 E 12(fA)152 192 S
(single\255precision float in native format.)-6 E 12(dA)152 204 S
(double\255precision float in native format.)-6 E 12(FA)152 228 S
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(DA)152 240 S(float of long\255double precision in native format.)-6 E
(\(Long doubles are available only if your system supports long)164 252
Q(double values _and_ if Perl has been compiled to support those.)170
264 Q(Raises an exception otherwise.\))194 276 Q 12(pA)152 300 S
(pointer to a null\255terminated string.)-6 E 12(PA)152 312 S
(pointer to a structure \(fixed\255length string\).)-6 E 12(uA)152 336 S
(uuencoded string.)-6 E 12(UA)152 348 S(Unicode character number.)-6 E
(Encodes to a character in character mode)12 E
(and UTF\2558 \(or UTF\255EBCDIC in EBCDIC platforms\) in byte mode.)176
360 Q 12(wA)152 384 S
(BER compressed integer \(not an ASN.1 BER, see perlpacktut for)-6 E 6
(details\). Its)170 396 R
(bytes represent an unsigned integer in base 128,)6 E
(most significant digit first, with as few digits as possible.)170 408 Q
(Bit)12 E(eight \(the high bit\) is set on each byte except the last.)
170 420 Q 12(xA)152 444 S
(null byte \(a.k.a ASCII NUL, "\\000", chr\(0\)\))-6 E 12(XB)152 456 S
(ack up a byte.)-12 E 12(@N)152 468 S
(ull\255fill or truncate to absolute position, counted from the)-12 E
(start of the innermost \(\)\255group.)170 480 Q 12(.N)152 492 S
(ull\255fill or truncate to absolute position specified by the value.)
-12 E 12(\(S)152 504 S(tart of a \(\)\255group.)-12 E F0 1.777
(One or more modi\214ers belo)128 522 R 4.277(wm)-.25 G 1.777
(ay optionally follo)-4.277 F 4.277(wc)-.25 G 1.777
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-.999 E F0 1.778(\(the second)4.278 F
(column lists letters for which the modi\214er is v)128 534 Q(alid\):)
-.25 E F1 18(!s)152 552 S 24(SlLiI Forces)-18 F
(native \(short, long, int\) sizes instead)6 E
(of fixed \(16\255/32\255bit\) sizes.)242 564 Q 48(xX Make)176 588 R 6
(xa)6 G(nd X act as alignment commands.)-6 E 36(nNvV Treat)176 612 R
(integers as signed instead of unsigned.)6 E 48(@. Specify)176 636 R
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(representation of the packed string. Efficient but)242 648 Q
(dangerous.)242 660 Q 18(>s)152 684 S 12(SiIlLqQ Force)-18 F
(big\255endian byte\255order on the type.)6 E 12(jJfFdDpP \(The)176 696
R("big end" touches the construct.\))6 E 18(<s)152 720 S 12
(SiIlLqQ Force)-18 F(little\255endian byte\255order on the type.)6 E F0
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(The)128 102 Q F1(>)5.14 E F0(and)5.14 E F1(<)5.14 E F0 2.64
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(The follo)128 132 Q(wing rules apply:)-.25 E<83>128 148.8 Q 1.792
(Each letter may optionally be follo)148 148.8 R 1.792
(wed by a number indicating the repeat count.)-.25 F 4.293(An)6.793 G
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F0 6.79(.T)C(he)-6.79 E .493(repeat count gobbles that man)148 172.8 R
2.994(yv)-.15 G .494(alues from the)-3.244 F/F2 9/Times-Roman@0 SF(LIST)
2.994 E F0 .494(when used with all format types other than)2.994 F F1(a)
148 184.8 Q F0(,)A F1(A)2.838 E F0(,)A F1(Z)2.838 E F0(,)A F1(b)2.838 E
F0(,)A F1(B)2.838 E F0(,)A F1(h)2.838 E F0(,)A F1(H)2.838 E F0(,)A F1(@)
2.838 E F0(,)A F1(.)2.838 E F0(,)A F1(x)2.838 E F0(,)A F1(X)2.838 E F0
2.838(,a)C(nd)-2.838 E F1(P)2.838 E F0 2.838(,w)C .338
(here it means something else, dscribed belo)-2.838 F 4.138 -.65(w. S)
-.25 H(upplying).65 E(a)148 196.8 Q F1(*)3.4 E F0 .9
(for the repeat count instead of a number means to use ho)3.4 F(we)-.25
E -.15(ve)-.25 G 3.401(rm).15 G(an)-3.401 E 3.401(yi)-.15 G .901
(tems are left, e)-3.401 F(xcept)-.15 E(for:)148 208.8 Q<83>148 225.6 Q
F1(@)168 225.6 Q F0(,)A F1(x)2.5 E F0 2.5(,a)C(nd)-2.5 E F1(X)2.5 E F0
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F0(.)A<83>148 242.4 Q(<.>, where it means relati)168 242.4 Q .3 -.15
(ve t)-.25 H 2.5(ot).15 G(he start of the string.)-2.5 E<83>148 259.2 Q
F1(u)168 259.2 Q F0 2.5(,w)C(here it is equi)-2.5 E -.25(va)-.25 G
(lent to 1 \(or 45, which here is equi).25 E -.25(va)-.25 G(lent\).).25
E 1.388(One can replace a numeric repeat count with a template letter e\
nclosed in brack)148 277.2 R 1.387(ets to use the)-.1 F(pack)148 289.2 Q
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-.1 E -.15(Fo)148 307.2 S 3.008(re).15 G .508(xample, the template)
-3.158 F F1(x[L])3.009 E F0 .509(skips as man)3.009 F 3.009(yb)-.15 G
.509(ytes as in a pack)-3.009 F .509(ed long, and the template)-.1 F F1
("$t)3.009 E .598(X[$t] $t")148 319.2 R F0 .598(unpacks twice whate)
3.098 F -.15(ve)-.25 G(r).15 E F1($t)3.098 E F0 .597(\(when v)3.098 F
(ariable-e)-.25 E .597(xpanded\) unpacks.)-.15 F .597
(If the template in)5.597 F(brack)148 331.2 Q .34
(ets contains alignment commands \(such as)-.1 F F1(x![d])2.84 E F0 .34
(\), its pack)B .34(ed length is calculated as if the)-.1 F
(start of the template had the maximal possible alignment.)148 343.2 Q
1.889(When used with)148 361.2 R F1(Z)4.389 E F0 4.389(,a)C F1(*)A F0
1.889
(as the repeat count is guaranteed to add a trailing null byte, so the)
4.389 F(resulting string is al)148 373.2 Q -.1(wa)-.1 G
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(When used with)148 391.2 Q F1(@)2.5 E F0 2.5(,t)C
(he repeat count represents an of)-2.5 E
(fset from the start of the innermost)-.25 E F1(\(\))2.5 E F0(group.)2.5
E .622(When used with)148 409.2 R F1(.)3.122 E F0 3.122(,t)C .623
(he repeat count determines the starting position to calculate the v)
-3.122 F .623(alue of)-.25 F(fset)-.25 E(as follo)148 421.2 Q(ws:)-.25 E
<83>148 438 Q(If the repeat count is)168 438 Q F1(0)2.5 E F0 2.5(,i)C
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(he current position.)-2.5 E<83>148 454.8 Q(If the repeat count is)168
454.8 Q F1(*)2.5 E F0 2.5(,t)C(he of)-2.5 E(fset is relati)-.25 E .3
-.15(ve t)-.25 H 2.5(ot).15 G(he start of the pack)-2.5 E(ed string.)-.1
E<83>148 471.6 Q .019(And if it')168 471.6 R 2.519(sa)-.55 G 2.519(ni)
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2.519(,t)C .019(he of)-2.519 F .019(fset is relati)-.25 F .319 -.15
(ve t)-.25 H 2.519(ot).15 G .018(he start of the)-2.519 F F3(n)2.518 E
F0 .018(th innermost)B F1 6.018(\(\))2.518 G F0 .018(group, or to)-3.5 F
(the start of the string if)168 483.6 Q F3(n)2.5 E F0
(is bigger then the group le)2.5 E -.15(ve)-.25 G(l.).15 E .075
(The repeat count for)148 501.6 R F1(u)2.575 E F0 .075(is interpreted a\
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h 0, 1 and 2 replaced by 45. The repeat count should not be more than 6\
5.)148 513.6 Q<83>128 530.4 Q(The)148 530.4 Q F1(a)2.863 E F0(,)A F1(A)
2.863 E F0 2.863(,a)C(nd)-2.863 E F1(Z)2.863 E F0 .363
(types gobble just one v)2.863 F .363(alue, b)-.25 F .363
(ut pack it as a string of length count, padding with)-.2 F 2.027
(nulls or spaces as needed.)148 542.4 R 2.027(When unpacking,)7.027 F F1
(A)4.527 E F0 2.027(strips trailing whitespace and nulls,)4.527 F F1(Z)
4.528 E F0(strips)4.528 E -2.15 -.25(ev e)148 554.4 T
(rything after the \214rst null, and).25 E F1(a)2.5 E F0
(returns data with no stripping at all.)2.5 E .997(If the v)148 572.4 R
.997(alue to pack is too long, the result is truncated.)-.25 F .996
(If it')5.996 F 3.496(st)-.55 G .996(oo long and an e)-3.496 F .996
(xplicit count is)-.15 F(pro)148 584.4 Q(vided,)-.15 E F1(Z)4.509 E F0
2.009(packs only)4.509 F F1($count\2551)4.509 E F0 2.009(bytes, follo)
4.509 F 2.009(wed by a null byte.)-.25 F(Thus)7.01 E F1(Z)4.51 E F0(al)
4.51 E -.1(wa)-.1 G 2.01(ys packs a).1 F(trailing null, e)148 596.4 Q
(xcept when the count is 0.)-.15 E<83>128 613.2 Q(Lik)148 613.2 Q -.25
(ew)-.1 G 2.309(ise, the).25 F F1(b)4.809 E F0(and)4.808 E F1(B)4.808 E
F0 2.308(formats pack a string that')4.808 F 4.808(st)-.55 G 2.308
(hat man)-4.808 F 4.808(yb)-.15 G 2.308(its long.)-4.808 F 2.308
(Each such format)7.308 F(generates 1 bit of the result.)148 625.2 Q
(These are typically follo)5 E(wed by a repeat count lik)-.25 E(e)-.1 E
F1(B8)2.5 E F0(or)2.5 E F1(B64)2.5 E F0(.)A .96(Each result bit is base\
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148 643.2 R 3.46(,i)-.4 G .96(.e., on)-3.46 F F1(ord\($char\)%2)148
655.2 Q F0 5.44(.I)C 2.94(np)-5.44 G(articular)-2.94 E 2.94(,c)-.4 G
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(generate bits 0 and 1, as do characters)2.94 F F1("\\000")148 667.2 Q
F0(and)2.5 E F1("\\001")2.5 E F0(.)A 1.918(Starting from the be)148
685.2 R 1.919
(ginning of the input string, each 8\255tuple of characters is con)-.15
F -.15(ve)-.4 G 1.919(rted to 1).15 F 2.382(character of output.)148
697.2 R -.4(Wi)7.382 G 2.382(th format).4 F F1(b)4.882 E F0 4.882(,t)C
2.381(he \214rst character of the 8\255tuple determines the least-)
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2.5 E F0 2.5(,i)C 2.5(td)-2.5 G
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(string were padded by null characters at the end.)148 84 R 1.078
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longer than needed, remaining characters are ignored.)148 114 Q(A)148
132 Q/F1 10/Courier@0 SF(*)2.606 E F0 .106
(for the repeat count uses all characters of the input \214eld.)2.606 F
.106(On unpacking, bits are con)5.106 F -.15(ve)-.4 G .107(rted to).15 F
2.5(as)148 144 S(tring of)-2.5 E F1(0)2.5 E F0 2.5(sa)C(nd)-2.5 E F1(1)
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(xadecimal)-.15 E(digits,)148 172.8 Q F1 -3.5("0".."9" "a".."f")2.5 F F0
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(ach such format,)-4.065 F/F2 10/Times-Italic@0 SF(pac)4.065 E(k\(\))-.2
E F0 1.565(generates 4 bits of result.)4.065 F -.4(Wi)6.566 G 1.566
(th non-alphabetical characters, the).4 F .129(result is based on the 4\
 least-signi\214cant bits of the input character)148 202.8 R 2.629(,i)
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-5.129 E(particular)148 214.8 Q 2.697(,c)-.4 G(haracters)-2.697 E F1
("0")2.697 E F0(and)2.697 E F1("1")2.697 E F0 .197(generate n)2.697 F
.197(ybbles 0 and 1, as do bytes)-.15 F F1("\\000")2.698 E F0(and)2.698
E F1("\\001")2.698 E F0(.)A -.15(Fo)148 226.8 S 3.145(rc).15 G
(haracters)-3.145 E F1("a".."f")3.145 E F0(and)3.145 E F1("A".."F")3.145
E F0 3.145(,t)C .645(he result is compatible with the usual he)-3.145 F
(xadecimal)-.15 E 1.252(digits, so that)148 238.8 R F1("a")3.752 E F0
(and)3.752 E F1("A")3.752 E F0 1.252(both generate the n)3.752 F(ybble)
-.15 E F1(0xA==10)3.752 E F0 6.252(.U)C 1.252
(se only these speci\214c he)-6.252 F(x)-.15 E
(characters with this format.)148 250.8 Q 1.072(Starting from the be)148
268.8 R 1.072(ginning of the template to)-.15 F F2(pac)3.572 E(k\(\))-.2
E F0 3.572(,e)C 1.072(ach pair of characters is con)-3.572 F -.15(ve)-.4
G 1.071(rted to 1).15 F .482(character of output.)148 280.8 R -.4(Wi)
5.483 G .483(th format).4 F F1(h)2.983 E F0 2.983(,t)C .483
(he \214rst character of the pair determines the least-signi\214cant)
-2.983 F -.15(ny)148 292.8 S(bble of the output character; with format)
.15 E F1(H)2.5 E F0 2.5(,i)C 2.5(td)-2.5 G
(etermines the most-signi\214cant n)-2.5 E(ybble.)-.15 E .359
(If the length of the input string is not e)148 310.8 R -.15(ve)-.25 G
.359(n, it beha).15 F -.15(ve)-.2 G 2.859(sa).15 G 2.859(si)-2.859 G
2.859(fp)-2.859 G .359(added by a null character at the end.)-2.859 F
(Similarly)148 322.8 Q 2.5(,`)-.65 G(`e)-3.24 E(xtra')-.15 E 2.5('n)-.74
G(ybbles are ignored during unpacking.)-2.65 E
(If the input string is longer than needed, e)148 340.8 Q
(xtra characters are ignored.)-.15 E(A)148 358.8 Q F1(*)2.528 E F0 .028
(for the repeat count uses all characters of the input \214eld.)2.528 F
-.15(Fo)5.028 G(r).15 E F2(unpac)2.529 E(k\(\))-.2 E F0 2.529(,n)C .029
(ybbles are con)-2.679 F -.15(ve)-.4 G(rted).15 E(to a string of he)148
370.8 Q(xadecimal digits.)-.15 E<83>128 387.6 Q(The)148 387.6 Q F1(p)
3.441 E F0 .941(format packs a pointer to a null-terminated string.)
3.441 F -1.1(Yo)5.941 G 3.44(ua)1.1 G .94
(re responsible for ensuring that)-3.44 F .057
(the string is not a temporary v)148 399.6 R .058
(alue, as that could potentially get deallocated before you got around)
-.25 F .077(to using the pack)148 411.6 R .077(ed result.)-.1 F(The)
5.077 E F1(P)2.577 E F0 .076
(format packs a pointer to a structure of the size indicated by the)
2.576 F 3.154(length. A)148 423.6 R .654
(null pointer is created if the corresponding v)3.154 F .654(alue for)
-.25 F F1(p)3.154 E F0(or)3.154 E F1(P)3.154 E F0(is)3.154 E F1(undef)
3.154 E F0 3.155(;s)C .655(imilarly with)-3.155 F F2(unpac)148 435.6 Q
(k\(\))-.2 E F0 2.5(,w)C(here a null pointer unpacks into)-2.5 E F1
(undef)2.5 E F0(.)A .123(If your system has a strange pointer size)148
453.6 R 1.666<8a6d>1.666 G .123
(eaning a pointer is neither as big as an int nor as big)-1.666 F .506
(as a long)148 465.6 R 1.666<8a69>1.666 G 3.007(tm)-1.666 G .507(ay not\
 be possible to pack or unpack pointers in big\255 or little-endian byt\
e order)-3.007 F(.)-.55 E(Attempting to do so raises an e)148 477.6 Q
(xception.)-.15 E<83>128 494.4 Q(The)148 494.4 Q F1(/)2.764 E F0 .264
(template character allo)2.764 F .264
(ws packing and unpacking of a sequence of items where the pack)-.25 F
(ed)-.1 E .745(structure contains a pack)148 506.4 R .745
(ed item count follo)-.1 F .745(wed by the pack)-.25 F .745
(ed items themselv)-.1 F 3.245(es. This)-.15 F .745(is useful)3.245 F
.405(when the structure you')148 518.4 R .404(re unpacking has encoded \
the sizes or repeat counts for some of its \214elds)-.5 F
(within the structure itself as separate \214elds.)148 530.4 Q -.15(Fo)
148 548.4 S(r).15 E F1(pack)3.759 E F0 3.759(,y)C 1.259(ou write)-3.759
F F2(length-item)3.759 E F1(/)A F2(sequence-item)A F0 3.759(,a)C 1.259
(nd the)-3.759 F F2(length-item)3.759 E F0 1.259(describes ho)3.759 F
3.759(wt)-.25 G 1.26(he length)-3.759 F -.25(va)148 560.4 S .298
(lue is pack).25 F .298(ed. F)-.1 F .298(ormats lik)-.15 F .298
(ely to be of most use are inte)-.1 F(ger)-.15 E .297(-packing ones lik)
-.2 F(e)-.1 E F1(n)2.797 E F0 .297(for Ja)2.797 F .797 -.25(va s)-.2 H
(trings,).25 E F1(w)148 572.4 Q F0(for)2.5 E/F3 9/Times-Roman@0 SF(ASN)
2.5 E F0(.1 or)A F3(SNMP)2.5 E F0 2.5(,a)C(nd)-2.5 E F1(N)2.5 E F0
(for Sun)2.5 E F3(XDR)2.5 E F0(.)A -.15(Fo)148 590.4 S(r).15 E F1(pack)
3.417 E F0(,)A F2(sequence-item)3.417 E F0 .917(may ha)3.417 F 1.217
-.15(ve a r)-.2 H .918
(epeat count, in which case the minimum of that and the).15 F .012
(number of a)148 602.4 R -.25(va)-.2 G .011
(ilable items is used as the ar).25 F .011(gument for)-.18 F F2
(length-item)2.511 E F0 2.511(.I)C 2.511(fi)-2.511 G 2.511(th)-2.511 G
.011(as no repeat count or uses)-2.511 F 2.5(a')148 614.4 S
(*', the number of a)-2.5 E -.25(va)-.2 G(ilable items is used.).25 E
-.15(Fo)148 632.4 S(r).15 E F1(unpack)5.679 E F0 5.679(,a)C 5.679(ni)
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(guments unpack)-.18 F 3.179(ed so f)-.1 F 3.18(ar is used. Y)-.1 F 3.18
(ou write)-1.1 F F1(/)148 644.4 Q F2(sequence-item)A F0 .681
(and the repeat count is obtained by popping of)3.181 F 3.181(ft)-.25 G
.68(he last element from the stack.)-3.181 F(The)148 656.4 Q F2
(sequence-item)2.5 E F0(must not ha)2.5 E .3 -.15(ve a r)-.2 H
(epeat count.).15 E(If)148 674.4 Q F2(sequence-item)3.108 E F0 .608
(refers to a string type \()3.108 F F1("A")A F0(,)A F1("a")3.108 E F0
3.108(,o)C(r)-3.108 E F1("Z")3.108 E F0 .608(\), the)B F2(length-item)
3.108 E F0 .609(is the string length,)3.108 F .257
(not the number of strings.)148 686.4 R -.4(Wi)5.257 G .257(th an e).4 F
.257(xplicit repeat count for pack, the pack)-.15 F .257
(ed string is adjusted to)-.1 F(that length.)148 698.4 Q -.15(Fo)5 G 2.5
(re).15 G(xample:)-2.65 E(perl v5.14.2)72 768 Q 198.17(2011-10-01 51)
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(unpack\("a3/A A*", "007 Bond)172 96 Q 6(J")12 G 42(\)g)-6 G
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1.319(ger types)-.15 F F1(s)3.819 E F0(,)A F1(S)3.819 E F0(,)A F1(l)
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(as seen by the local C compiler may be lar)148 244.8 R(ger)-.18 E 5.303
(.T)-.55 G .303(his is mainly an issue on 64\255bit platforms.)-5.303 F
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(mak)2.5 E(es an)-.1 E 2.5(yd)-.15 G(if)-2.5 E(ference this w)-.25 E
(ay:)-.1 E F1(printf "format s is %d, s! is %d\\n",)172 274.8 Q
(length pack\("s"\), length pack\("s!"\);)196 286.8 Q
(printf "format l is %d, l! is %d\\n",)172 310.8 Q
(length pack\("l"\), length pack\("l!"\);)196 322.8 Q(i!)148 340.8 Q F0
(and)2.5 E F1(I!)2.5 E F0(are also allo)2.5 E(wed, b)-.25 E
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(re identical to)-2.5 E F1(i)2.5 E F0(and)2.5 E F1(I)2.5 E F0(.)A .242
(The actual sizes \(in bytes\) of nati)148 358.8 R .542 -.15(ve s)-.25 H
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-.1(wa)148 370.8 S 2.5(sb).1 G(uilt are also a)-2.7 E -.25(va)-.2 G
(ilable from the command line:).25 E F1 6($p)172 388.8 S
(erl \255V:{short,int,long{,long}}size)-6 E(shortsize=\0102\010;)172
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(longlongsize=\0108\010;)172 436.8 Q F0(or programmatically via the)148
454.8 Q F1(Config)2.5 E F0(module:)2.5 E F1(use Config;)190 472.8 Q
(print $Config{shortsize},)190 484.8 Q("\\n";)24 E
(print $Config{intsize},)190 496.8 Q("\\n";)36 E
(print $Config{longsize},)190 508.8 Q("\\n";)30 E
(print $Config{longlongsize}, "\\n";)190 520.8 Q($Config{longlongsize})
148 538.8 Q F0(is unde\214ned on systems without long long support.)2.5
E<83>128 555.6 Q .118(The inte)148 555.6 R .118(ger formats)-.15 F F1(s)
2.618 E F0(,)A F1(S)2.618 E F0(,)A F1(i)2.618 E F0(,)A F1(I)2.618 E F0
(,)A F1(l)2.618 E F0(,)A F1(L)2.618 E F0(,)A F1(j)2.618 E F0 2.618(,a)C
(nd)-2.618 E F1(J)2.618 E F0 .119
(are inherently non-portable between processors and)2.618 F 1.384
(operating systems because the)148 567.6 R 3.884(yo)-.15 G(be)-3.884 E
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(ger 0x12345678 \(305419896 decimal\) w)-.15 F .181
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(Basically)148 639.6 Q 5.311(,I)-.65 G 2.811(ntel and)-5.311 F F3 -1.215
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651.6 Q F3(PPC)3.241 E F0 3.241(,S)C(parc,)-3.241 E F3 .991(HP P)3.241 F
(A)-.828 E F0 3.241(,P)C -.25(ow)-3.241 G(er).25 E 3.241(,a)-.4 G .741
(nd Cray)-3.241 F 3.241(,a)-.65 G .741(re big-endian.)-3.241 F .741
(Alpha and)5.741 F F3(MIPS)3.241 E F0 .742(can be either:)3.241 F 1.559
(Digital/Compaq uses \(well, used\) them in little-endian mode, b)148
663.6 R 1.559(ut SGI/Cray uses them in big-)-.2 F(endian mode.)148 675.6
Q .238(The names)148 693.6 R F2(big-endian)2.738 E F0(and)2.738 E F2
(little-endian)2.738 E F0 .239(are comic references to the e)2.738 F
.239(gg-eating habits of the little-)-.15 F 2.357(endian Lilliputians a\
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148 705.6 R F2(Gulliver')148 717.6 Q 3.944(sT)-.4 G -.15(ra)-4.494 G
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(his entered computer lingo via the paper `)-6.444 F 1.444(`On Holy W)
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2.5 F F0(137, April 1, 1980.)2.5 E(perl v5.14.2)72 768 Q 198.17
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(0x56 0x78 0x12 0x34)166 102 Q(0x34 0x12 0x78 0x56)166 114 Q F0 -1.1(Yo)
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(printf\("%#02x ", $_\) for unpack\("W*", pack L=>0x12345678\);)166 150
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(use Config;)172 186 Q(print "$Config{byteorder}\\n";)172 198 Q F0
(or from the command line:)148 216 Q F1 6($p)172 234 S
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(and)3.56 E F1("12345678")3.56 E F0 1.06(are little-endian;)3.56 F F1
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F1(n)4.317 E F0(,)A F1(N)4.317 E F0(,)A F1(v)4.317 E F0 4.317(,a)C(nd)
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294 Q 3.8 -.65(w. S)-.25 H(ee also perlport.).65 E<83>128 310.8 Q .882
(Starting with Perl 5.9.2, inte)148 310.8 R .882
(ger and \215oating-point formats, along with the)-.15 F F1(p)3.382 E F0
(and)3.382 E F1(P)3.382 E F0 .882(formats and)3.382 F F1(\(\))148 322.8
Q F0 .625(groups, may all be follo)3.125 F .625(wed by the)-.25 F F1(>)
3.126 E F0(or)3.126 E F1(<)3.126 E F0 .626
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(don')3.018 E(t)-.18 E(co)148 346.8 Q -.15(ve)-.15 G 2.5(rs).15 G
(igned inte)-2.5 E(gers, 64\255bit inte)-.15 E
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(Here are some concerns to k)148 364.8 Q
(eep in mind when using an endianness modi\214er:)-.1 E<83>148 381.6 Q
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.157(ferent platforms w)-.25 F .158(orks only when all platforms store)
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(Most platforms store signed inte)8.111 F 3.111(gers in tw)-.15 F(o')-.1
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405.6 Q<83>148 422.4 Q(The)168 422.4 Q F1(>)3.922 E F0(or)3.922 E F1(<)
3.922 E F0 1.422(modi\214ers can only be used on \215oating-point forma\
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434.4 R(attempting to use them raises an e)2.5 E(xception.)-.15 E<83>148
451.2 Q -.15(Fo)168 451.2 S .359
(rcing big\255 or little-endian byte-order on \215oating-point v).15 F
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(only if all platforms use the same binary representation such as)168
463.2 R/F2 9/Times-Roman@0 SF(IEEE)2.812 E F0 2.812
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-.1 E(alues.)-.25 E<83>148 516 Q .909(When using)168 516 R F1(>)3.409 E
F0(or)3.409 E F1(<)3.409 E F0 .909(on a)3.409 F F1(\(\))3.409 E F0 .909
(group, this af)3.409 F .909
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(order modi\214ers, including all subgroups.)168 528 R .879
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(IEEE)2.682 E F0 .181(\215oating-point arithmetic \(because)2.682 F
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616.8 Q F2(IEEE)2.5 E F0 2.5(spec\). See)2.5 F(also perlport.)2.5 E .692
(If you kno)148 634.8 R(w)-.25 E/F3 10/Times-Italic@0 SF -.2(ex)3.192 G
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(Because Perl uses doubles \(or long doubles, if con\214gured\) interna\
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(ain loses precision, so)-.05 F F1(unpack\("f",)2.968 E
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(CE.B1.CF.89)172 216 Q 6($p)172 228 S
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(CE.B1.CF.89)172 252 Q 6($p)172 264 S
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(C3.8E.C2.B1.C3.8F.C2.89)172 288 Q F0 .941(Those e)148 306 R .941
(xamples also illustrate that you should not try to use)-.15 F F1(pack)
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(coming from, so the)148 358.8 Q 2.5(yh)-.15 G
(andle their output and input as \215at sequences of characters.)-2.5 E
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4.011(Ag)6.511 G 1.512(roup may tak)-4.011 F 4.012(ear)-.1 G 1.512
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435.6 Q F1("\\0X\\0\\0YZ")2.5 E F0(.)A<83>128 452.4 Q F1(x)148 452.4 Q
F0(and)3.202 E F1(X)3.202 E F0 .702(accept the)3.202 F F1(!)3.202 E F0
.702(modi\214er to act as alignment commands: the)3.202 F 3.202(yj)-.15
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(pac)3.036 E(k\(\))-.2 E F0(or)3.036 E F2(unpac)3.036 E(k\(\))-.2 E F0
(a)3.036 E 2.5(Cs)148 476.4 S(tructure lik)-2.5 E(e)-.1 E F1(struct {)
172 494.4 Q 12(char c;)196 506.4 R(/* one signed, 8\255bit character */)
24 E(double d;)196 518.4 Q 12(char cc[2];)196 530.4 R(})172 542.4 Q F0
1.63(one may need to use the template)148 560.4 R F1 7.63(cx)4.13 G 1.63
(![d] d c[2])-7.63 F F0 6.63(.T)C 1.63(his assumes that doubles must be)
-6.63 F(aligned to the size of double.)148 572.4 Q -.15(Fo)148 590.4 S
2.5(ra).15 G(lignment commands, a)-2.5 E F1(count)2.5 E F0(of 0 is equi)
2.5 E -.25(va)-.25 G(lent to a).25 E F1(count)2.5 E F0
(of 1; both are no-ops.)2.5 E<83>128 607.2 Q F1(n)148 607.2 Q F0(,)A F1
(N)2.975 E F0(,)A F1(v)2.975 E F0(and)2.975 E F1(V)2.975 E F0 .475
(accept the)2.975 F F1(!)2.975 E F0 .474
(modi\214er to represent signed 16\255/32\255bit inte)2.975 F .474
(gers in big\255/little\255endian)-.15 F(order)148 619.2 Q 7.892(.T)-.55
G 2.892(his is portable only when all platforms sharing pack)-7.892 F
2.892(ed data use the same binary)-.1 F 3.274
(representation for signed inte)148 631.2 R 3.274(gers; for e)-.15 F
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3.232 E(TE)-.999 E F0(using)3.232 E F1(#)3.233 E F0 .733
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(separate pack codes from each other)148 672 R 3.437(,b)-.4 G .937
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(as much to impro)148 696 R 3.522 -.15(ve l)-.15 H -.15(eg).15 G 3.222
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S(ame thing with Unicode circled letters. You don\010t get the UTF\2558)
-6 E 6(#b)152 228 S
(ytes because the U at the start of the format caused a switch to)-6 E 6
(#U)152 240 S
(0\255mode, so the UTF\2558 bytes get joined into characters)-6 E
($foo = pack\("C0U4",0x24b6,0x24b7,0x24b8,0x24b9\);)152 252 Q 6(#f)152
264 S
(oo eq "\\xe2\\x92\\xb6\\xe2\\x92\\xb7\\xe2\\x92\\xb8\\xe2\\x92\\xb9")-6
E 6(#T)152 276 S
(his is the UTF\2558 encoding of the string in the previous example)-6 E
($foo = pack\("ccxxcc",65,66,67,68\);)152 300 Q 6(#f)152 312 S
(oo eq "AB\\0\\0CD")-6 E 6(#N)152 336 S
(OTE: The examples above featuring "W" and "c" are true)-6 E 6(#o)152
348 S(nly on ASCII and ASCII\255derived systems such as ISO Latin 1)-6 E
6(#a)152 360 S(nd UTF\2558.)-6 E
(On EBCDIC systems, the first example would be)12 E 36(#$)152 372 S
(foo = pack\("WWWW",193,194,195,196\);)-36 E($foo = pack\("s2",1,2\);)
152 396 Q 6(#")152 408 S(\\001\\000\\002\\000" on little\255endian)-6 E
6(#")152 420 S(\\000\\001\\000\\002" on big\255endian)-6 E
($foo = pack\("a4","abcd","x","y","z"\);)152 444 Q 6(#")152 456 S(abcd")
-6 E($foo = pack\("aaaa","abcd","x","y","z"\);)152 480 Q 6(#")152 492 S
(axyz")-6 E($foo = pack\("a14","abcdefg"\);)152 516 Q 6(#")152 528 S
(abcdefg\\0\\0\\0\\0\\0\\0\\0")-6 E($foo = pack\("i9pl", gmtime\);)152
552 Q 6(#ar)152 564 S(eal struct tm \(on my system anyway\))-6 E
($utmp_template = "Z8 Z8 Z16 L";)152 588 Q
($utmp = pack\($utmp_template, @utmp1\);)152 600 Q 6(#as)152 612 S
(truct utmp \(BSDish\))-6 E(@utmp2 = unpack\($utmp_template, $utmp\);)
152 636 Q 6(#")152 648 S(@utmp1" eq "@utmp2")-6 E(sub bintodec {)152 672
Q(unpack\("N", pack\("B32", substr\("0" x 32 . shift, \25532\)\)\);)176
684 Q(})152 696 Q($foo = pack\(\010sx2l\010, 12, 34\);)152 720 Q F0
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(The same template may generally also be used in)128 270 Q/F2 10
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9/Times-Roman@0 SF -.315(NA)2.5 G(MESP).315 E -.36(AC)-.828 G(E).36 E F0
(package)108 298.8 Q F3 -.315(NA)2.5 G(MESP).315 E -.36(AC)-.828 G 2.5
(EV).36 G(ERSION)-2.5 E F0(package)108 310.8 Q F3 -.315(NA)2.5 G(MESP)
.315 E -.36(AC)-.828 G 2.5(EB).36 G(LOCK)-2.5 E F0(package)108 322.8 Q
F3 -.315(NA)2.5 G(MESP).315 E -.36(AC)-.828 G 2.5(EV).36 G .25
(ERSION BLOCK)-2.5 F F0 .141(Declares the)128 334.8 R F3(BLOCK)2.641 E
F0 .141(or the rest of the compilation unit as being in the gi)2.641 F
-.15(ve)-.25 G 2.64(nn).15 G 2.64(amespace. The)-2.64 F .14(scope of)
2.64 F .92(the package declaration is either the supplied code)128 346.8
R F3(BLOCK)3.42 E F0(or)3.42 E 3.421(,i)-.4 G 3.421(nt)-3.421 G .921
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(BLOCK)3.157 E F0 .657(are operati)3.157 F .957 -.15(ve t)-.25 H .657
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3.13 F -.15(ve)-.25 G 3.129(nn).15 G(amespace,)-3.129 E -.15(ex)128
394.8 S 3.02(cept where o).15 F -.15(ve)-.15 G 3.02(rridden by another)
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3.02(re one of the special)-.5 F(identi\214ers that qualify into)128
406.8 Q F1(main::)2.5 E F0 2.5(,l)C(ik)-2.5 E(e)-.1 E F1(STDOUT)2.5 E F0
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F1(local)3.226 E F0 .726(on, b)3.226 F(ut)-.2 E F2(not)3.226 E F0(le)128
436.8 Q 2.853(xical v)-.15 F 2.853(ariables, which are created with)-.25
F F1(my)5.353 E F0(,)A F1(state)5.353 E F0 5.353(,o)C(r)-5.353 E F1(our)
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448.8 R F1(require)3.108 E F0(or)3.108 E F1(use)3.108 E F0 5.608(.Y)C
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(block. Y)128 472.8 R 1.032(ou can refer to identi\214ers in other pack\
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(with the package name and a double colon, as in)128 484.8 R F1
($SomePack::var)13.484 E F0(or)13.484 E F1(ThatPack::INPUT_HANDLE)128
496.8 Q F0 6.056(.I)C 3.556(fp)-6.056 G 1.056
(ackage name is omitted, the)-3.556 F F1(main)3.555 E F0 1.055
(package as assumed.)3.555 F(That)6.055 E(is,)128 508.8 Q F1($::sail)
2.727 E F0 .227(is equi)2.727 F -.25(va)-.25 G .227(lent to).25 F F1
($main::sail)2.727 E F0 .227(\(as well as to)2.727 F F1($main\010sail)
2.727 E F0 2.728(,s)C .228(till seen in ancient code,)-2.728 F
(mostly from Perl 4\).)128 520.8 Q(If)128 538.8 Q F3(VERSION)3.027 E F0
.527(is pro)3.027 F(vided,)-.15 E F1(package)3.026 E F0 .526(sets the)
3.026 F F1($VERSION)3.026 E F0 -.25(va)3.026 G .526(riable in the gi).25
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-.15 E .666(object with the)128 550.8 R F3(VERSION)3.166 E F0(pro)3.166
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(ecimal number \(inte).15 F .242(ger or decimal-fraction\) without e)
-.15 F .242(xponentiation or)-.15 F .369
(else a dotted-decimal v\255string with a leading ')128 574.8 R .369
(v' character and at least three components.)-.5 F -1.1(Yo)5.37 G 2.87
(us)1.1 G(hould)-2.87 E(set)128 586.8 Q F1($VERSION)2.5 E F0
(only once per package.)2.5 E .521(See `)128 604.8 R(`P)-.74 E(ackages')
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(pipe)108 633.6 Q F3(READHANDLE)2.5 E F0(,WRITEHANDLE)A .538
(Opens a pair of connected pipes lik)128 645.6 R 3.038(et)-.1 G .538
(he corresponding system call.)-3.038 F .538
(Note that if you set up a loop of)5.538 F .071
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-.55 G .07(ipes use)-2.57 F F3(IO)128 669.6 Q F0 -.2(bu)2.567 G -.25(ff)
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(to \215ush your)2.568 F F3(WRITEHANDLE)2.568 E F0 .068
(after each command, depending)2.568 F(on the application.)128 681.6 Q
1.24(See IPC::Open2, IPC::Open3, and `)128 699.6 R 1.24
(`Bidirectional Communication with Another Process')-.74 F 3.74('i)-.74
G 3.74(np)-3.74 G(erlipc)-3.74 E(for e)128 711.6 Q
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124.8 Q F3(EXPR)2.5 E F0(pop)108 136.8 Q(Pops and returns the last v)128
136.8 Q(alue of the array)-.25 E 2.5(,s)-.65 G
(hortening the array by one element.)-2.5 E 1.186
(Returns the unde\214ned v)128 154.8 R 1.186(alue if the array is empty)
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(ARRA)128 166.8 Q(Y)-.945 E F0 .765(is omitted, pops the)3.265 F F1
(@ARGV)3.265 E F0 .765(array in the main program, b)3.265 F .765(ut the)
-.2 F F1(@_)3.265 E F0 .765(array in subroutines, just)3.265 F(lik)128
178.8 Q(e)-.1 E F1(shift)2.5 E F0(.)A 1.31(Starting with Perl 5.14,)128
196.8 R F1(pop)3.81 E F0 1.31(can tak)3.81 F 3.81(eas)-.1 G(calar)-3.81
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(hich must hold a reference to an unblessed)-3.81 F(array)128 208.8 Q
6.647(.T)-.65 G 1.647(he ar)-6.647 F 1.646
(gument will be dereferenced automatically)-.18 F 6.646(.T)-.65 G 1.646
(his aspect of)-6.646 F F1(pop)4.146 E F0 1.646(is considered highly)
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-.15 E(pos)108 237.6 Q F3(SCALAR)2.5 E F0(pos)108 249.6 Q .315
(Returns the of)128 249.6 R .315(fset of where the last)-.25 F F1(m//g)
2.816 E F0 .316(search left of)2.816 F 2.816(ff)-.25 G .316(or the v)
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(ariable is not speci\214ed\). Note that 0 is a v)-.25 F 1.554
(alid match of)-.25 F(fset.)-.25 E F1(undef)4.054 E F0 1.554
(indicates that the search)4.054 F .709
(position is reset \(usually due to match f)128 273.6 R .709(ailure, b)
-.1 F .71(ut can also be because no match has yet been run on)-.2 F
(the scalar\).)128 285.6 Q F1(pos)128 303.6 Q F0 .683
(directly accesses the location used by the re)3.183 F(ge)-.15 E .683
(xp engine to store the of)-.15 F .683(fset, so assigning to)-.25 F F1
(pos)3.182 E F0 .726(will change that of)128 315.6 R .726
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(zero-width assertion in re)3.226 F .726(gular e)-.15 F(xpressions.)-.15
E .788(Both of these ef)128 327.6 R .788(fects tak)-.25 F 3.287(ep)-.1 G
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(ta)-.18 G -.25(ff)-3.287 G .787(ect the position with).25 F F1(pos)
3.287 E F0(during)3.287 E(the current match, such as in)128 339.6 Q F1
(\(?{pos\(\) = 5}\))2.5 E F0(or)2.5 E F1(s//pos\(\) = 5/e)2.5 E F0(.)A
(Setting)128 357.6 Q F1(pos)5.392 E F0 2.892(also resets the)5.392 F F2
(matc)5.392 E 2.892(hed with zer)-.15 F(o-length)-.45 E F0 2.893
(\215ag, described under `)5.393 F 2.893(`Repeated P)-.74 F(atterns)-.15
E(Matching a Zero-length Substring')128 369.6 Q 2.5('i)-.74 G 2.5(np)
-2.5 G(erlre.)-2.5 E 1.019(Because a f)128 387.6 R(ailed)-.1 E F1(m//gc)
3.518 E F0 1.018(match doesn')3.518 F 3.518(tr)-.18 G 1.018(eset the of)
-3.518 F 1.018(fset, the return from)-.25 F F1(pos)3.518 E F0 -.1(wo)
3.518 G(n').1 E 3.518(tc)-.18 G 1.018(hange either in)-3.518 F
(this case.)128 399.6 Q(See perlre and perlop.)5 E(print)108 416.4 Q F3
.25(FILEHANDLE LIST)2.5 F F0(print)108 428.4 Q F3(FILEHANDLE)2.5 E F0
(print)108 440.4 Q F3(LIST)2.5 E F0(print)108 452.4 Q .747
(Prints a string or a list of strings.)128 464.4 R .747
(Returns true if successful.)5.747 F F3(FILEHANDLE)5.747 E F0 .747
(may be a scalar v)3.247 F(ariable)-.25 E 1.85(containing the name of o\
r a reference to the \214lehandle, thus introducing one le)128 476.4 R
-.15(ve)-.25 G 4.35(lo).15 G 4.35(fi)-4.35 G(ndirection.)-4.35 E(\()128
488.4 Q F3(NO)A(TE:)-.36 E F0(If)3.959 E F3(FILEHANDLE)3.959 E F0 1.459
(is a v)3.959 F 1.459(ariable and the ne)-.25 F 1.459(xt tok)-.15 F
1.459(en is a term, it may be misinterpreted as an)-.1 F 2.3
(operator unless you interpose a)128 500.4 R F1(+)4.8 E F0 2.3
(or put parentheses around the ar)4.8 F 2.3(guments.\) If)-.18 F F3
(FILEHANDLE)4.8 E F0(is)4.8 E .949
(omitted, prints to the last selected \(see `)128 512.4 R(`select')-.74
E .949('\) output handle.)-.74 F(If)5.949 E F3(LIST)3.449 E F0 .949
(is omitted, prints)3.449 F F1($_)3.449 E F0 .949(to the)3.449 F .22
(currently selected output handle.)128 524.4 R 1.82 -.8(To u)5.22 H(se)
.8 E F3(FILEHANDLE)2.72 E F0 .219(alone to print the content of)2.72 F
F1($_)2.719 E F0 .219(to it, you must)2.719 F 2.165
(use a real \214lehandle lik)128 536.4 R(e)-.1 E F1(FH)4.665 E F0 4.665
(,n)C 2.165(ot an indirect one lik)-4.665 F(e)-.1 E F1($fh)4.666 E F0
7.166(.T)C 4.666(os)-7.966 G 2.166(et the def)-4.666 F 2.166
(ault output handle to)-.1 F(something other than)128 548.4 Q F3(STDOUT)
2.5 E F0 2.5(,u)C(se the select operation.)-2.5 E .079(The current v)128
566.4 R .079(alue of)-.25 F F1($,)2.579 E F0 .079(\(if an)2.579 F .079
(y\) is printed between each)-.15 F F3(LIST)2.579 E F0 2.578(item. The)
2.578 F .078(current v)2.578 F .078(alue of)-.25 F F1($\\)2.578 E F0
.078(\(if an)2.578 F .078(y\) is)-.15 F 1.423(printed after the entire)
128 578.4 R F3(LIST)3.923 E F0 1.424(has been printed.)3.923 F 1.424
(Because print tak)6.424 F 1.424(es a)-.1 F F3(LIST)3.924 E F0 3.924(,a)
C -.15(ny)-3.924 G 1.424(thing in the).15 F F3(LIST)3.924 E F0(is)3.924
E -.25(eva)128 590.4 S .486(luated in list conte).25 F .486
(xt, including an)-.15 F 2.985(ys)-.15 G .485
(ubroutines whose return lists you pass to)-2.985 F F1(print)2.985 E F0
5.485(.B)C 2.985(ec)-5.485 G(areful)-2.985 E 2.275(not to follo)128
602.4 R 4.775(wt)-.25 G 2.275(he print k)-4.775 F -.15(ey)-.1 G -.1(wo)
.15 G 2.275(rd with a left parenthesis unless you w).1 F 2.276
(ant the corresponding right)-.1 F .293(parenthesis to terminate the ar)
128 614.4 R .292(guments to the print; put parentheses around all ar)
-.18 F .292(guments \(or interpose)-.18 F(a)128 626.4 Q F1(+)2.5 E F0
2.5(,b)C(ut that doesn')-2.7 E 2.5(tl)-.18 G(ook as good\).)-2.5 E .191
(If you')128 644.4 R .191
(re storing handles in an array or hash, or in general whene)-.5 F -.15
(ve)-.25 G 2.691(ry).15 G(ou')-2.691 E .191(re using an)-.5 F 2.692(ye)
-.15 G .192(xpression more)-2.842 F(comple)128 656.4 Q 2.532(xt)-.15 G
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204 Q F1
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152 232.8 Q
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244.8 Q(closedir $dh;)152 256.8 Q F0
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(while \( ! eof\($fh\) \) {)152 591.6 Q
(defined\( $_ = <$fh> \) or die "readline failed: $!";)176 603.6 Q(...)
176 615.6 Q(})152 627.6 Q F0 .982(Note that you ha)128 645.6 R 1.282
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3.481 E F0 .981(errors that w)3.481 F .981(ay with the)-.1 F F2(ARGV)
3.481 E F0 .981(\214lehandle. In that case,)3.481 F(you ha)128 657.6 Q
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(cuted as a system command.).15 F .735
(The collected standard output of the command is returned.)5.735 F .35
(In scalar conte)128 225.6 R .35
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(\). This)B 1.759(is the)4.259 F .432
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(operator)2.932 E 2.932(,b)-.4 G .432(ut you can use it directly)-3.132
F 5.433(.T)-.65 G(he)-5.433 E F1(qx/EXPR/)2.933 E F0
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(he same \215ags as the system call of the same name.)-3.283 F .782
(Returns the address of the)5.783 F 1.822(sender if)128 326.4 R F2
(SOCKET)4.322 E F0 2.922 -.55('s p)D 1.822
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(epending on the status of the sock)-4.481 F 1.982
(et, either \(8\255bit\) bytes or characters are)-.1 F(recei)128 380.4 Q
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(binmode\(\))128 392.4 Q F0 .695(to operate with the)3.195 F F1
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(will operate on UTF8\255encoded Unicode characters, not bytes.)128
404.4 R .04(Similarly for the)5.04 F F1(:encoding)2.54 E F0(pragma:)2.54
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511.2 S(warning: assumes no { or } in strings\))-6 E
(LINE: while \(<STDIN>\) {)152 523.2 Q
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(while \(<STDIN>\) {)200 583.2 Q(if \(/}/\) {)224 595.2 Q 6(#e)12 G
(nd of comment?)-6 E(s|^|$front\\{|;)248 607.2 Q(redo LINE;)248 619.2 Q
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679.2 Q(redo)128 697.2 Q F0 .081
(cannot be used to retry a block that returns a v)2.58 F .081
(alue such as)-.25 F F1 .081(eval {})2.581 F F0(,)A F1 .081(sub {})2.581
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(foreach $prefix \(@INC\) {)194 318 Q
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(if \(\255f $realfilename\) {)218 342 Q
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(require)2.949 E F0 .449(looks for a ")2.949 F F2(.pm)A F0 1.929 -.74
(`` e)D .449(xtension, it will).59 F .198
(\214rst look for a similar \214lename with a ')128 228 R(')-.74 E F2
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(of an)128 240 Q 2.5<798c>-.15 G(le ending in a ')-2.5 E(')-.74 E F2
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(acility by putting Perl code directly into the)-.1 F F1(@INC)3.474 E F0
(array)3.474 E(.)-.65 E(There are three forms of hooks: subroutine refe\
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(Subroutine references are the simplest case.)128 288 R 1.632
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(encounters a subroutine, this subroutine gets called with tw)128 300 R
2.941(op)-.1 G .442(arameters, the \214rst a reference to itself,)-2.941
F .448(and the second the name of the \214le to be included \(e.g., ")
128 312 R F2 -1.05(Fo)C(o/Bar)1.05 E(.pm)-1.11 E F0 2.948("\). The)B
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(either nothing or else a list of up to three v)128 324 Q
(alues in the follo)-.25 E(wing order:)-.25 E(1.)128 340.8 Q 2.5<418c>
148 340.8 S(lehandle, from which the \214le will be read.)-2.5 E(2.)128
357.6 Q 4.413(Ar)148 357.6 S 1.913
(eference to a subroutine. If there is no \214lehandle \(pre)-4.413 F
1.914(vious item\), then this subroutine is)-.25 F -.15(ex)148 369.6 S
1.043(pected to generate one line of source code per call, writing the \
line into).15 F F1($_)3.543 E F0 1.043(and returning 1,)3.543 F .224
(then \214nally at end of \214le returning 0.)148 381.6 R .225
(If there is a \214lehandle, then the subroutine will be called to)5.225
F .169(act as a simple source \214lter)148 393.6 R 2.669(,w)-.4 G .169
(ith the line as read in)-2.669 F F1($_)2.669 E F0 5.169(.A)C -.05(ga)
-5.169 G .169(in, return 1 for each v).05 F .169(alid line, and 0)-.25 F
(after all lines ha)148 405.6 Q .3 -.15(ve b)-.2 H(een returned.).15 E
(3.)128 422.4 Q .476
(Optional state for the subroutine. The state is passed in as)148 422.4
R F1($_[1])2.976 E F0 -5.475 2.976(.A r)D .477
(eference to the subroutine)-2.976 F(itself is passed in as)148 434.4 Q
F1($_[0])2.5 E F0(.)A .656(If an empty list,)128 452.4 R F1(undef)3.156
E F0 3.156(,o)C 3.155(rn)-3.156 G .655
(othing that matches the \214rst 3 v)-3.155 F .655(alues abo)-.25 F .955
-.15(ve i)-.15 H 3.155(sr).15 G .655(eturned, then)-3.155 F F1(require)
3.155 E F0 .195(looks at the remaining elements of)128 464.4 R F1(@INC)
2.695 E F0 5.195(.N)C .195
(ote that this \214lehandle must be a real \214lehandle \(strictly a)
-5.195 F(type)128 476.4 Q .048(glob or reference to a type)-.15 F .047(\
glob, whether blessed or unblessed\); tied \214lehandles will be ignore\
d and)-.15 F(processing will stop there.)128 488.4 Q .776(If the hook i\
s an array reference, its \214rst element must be a subroutine referenc\
e.)128 506.4 R .777(This subroutine is)5.777 F .504(called as abo)128
518.4 R -.15(ve)-.15 G 3.003(,b).15 G .503
(ut the \214rst parameter is the array reference.)-3.203 F .503
(This lets you indirectly pass ar)5.503 F(guments)-.18 E
(to the subroutine.)128 530.4 Q(In other w)128 548.4 Q
(ords, you can write:)-.1 E F1(push @INC, \\&my_sub;)152 566.4 Q
(sub my_sub {)152 578.4 Q(my \($coderef, $filename\) = @_;)176 590.4 Q 6
(#$)12 G(coderef is \\&my_sub)-6 E(...)176 602.4 Q(})152 614.4 Q F0(or:)
128 632.4 Q(perl v5.14.2)72 768 Q 198.17(2011-10-01 64)162.62 F 0 Cg EP
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
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(push @INC, [ \\&my_sub, $x, $y, ... ];)152 84 Q(sub my_sub {)152 96 Q
(my \($arrayref, $filename\) = @_;)176 108 Q 6(#R)176 120 S
(etrieve $x, $y, ...)-6 E(my @parameters = @$arrayref[1..$#$arrayref];)
176 132 Q(...)176 144 Q(})152 156 Q F0 .183
(If the hook is an object, it must pro)128 174 R .184(vide an)-.15 F/F2
9/Times-Roman@0 SF(INC)2.684 E F0 .184
(method that will be called as abo)2.684 F -.15(ve)-.15 G 2.684(,t).15 G
.184(he \214rst parameter)-2.684 F .216(being the object itself.)128 186
R .216(\(Note that you must fully qualify the sub')5.216 F 2.716(sn)-.55
G .216(ame, as unquali\214ed)-2.716 F F1(INC)2.716 E F0 .215(is al)2.715
F -.1(wa)-.1 G(ys).1 E(forced into package)128 198 Q F1(main)2.5 E F0
2.5(.\) Here)B(is a typical code layout:)2.5 E F1 6(#I)152 216 S 6(nF)-6
G(oo.pm)-6 E(package Foo;)152 228 Q(sub new { ... })152 240 Q
(sub Foo::INC {)152 252 Q(my \($self, $filename\) = @_;)176 264 Q(...)
176 276 Q(})152 288 Q 6(#I)152 312 S 6(nt)-6 G(he main program)-6 E
(push @INC, Foo\255>new\(...\);)152 324 Q F0 .373
(These hooks are also permitted to set the)128 342 R F1(%INC)2.873 E F0
.373(entry corresponding to the \214les the)2.873 F 2.873(yh)-.15 G
-2.25 -.2(av e)-2.873 H .373(loaded. See)3.073 F -.74(``)128 354 S
(%INC').74 E 2.5('i)-.74 G 2.5(np)-2.5 G(erlv)-2.5 E(ar)-.25 E(.)-.55 E
-.15(Fo)128 372 S 2.5(ray).15 G(et-more-po)-2.5 E(werful import f)-.25 E
(acility)-.1 E 2.5(,s)-.65 G(ee `)-2.5 E(`use')-.74 E 2.5('a)-.74 G
(nd perlmod.)-2.5 E(reset)108 388.8 Q F2(EXPR)2.5 E F0(reset)108 400.8 Q
.46(Generally used in a)128 412.8 R F1(continue)2.96 E F0 .459
(block at the end of a loop to clear v)2.96 F .459(ariables and reset)
-.25 F F1(??)2.959 E F0 .459(searches so)2.959 F .455(that the)128 424.8
R 2.955(yw)-.15 G .455(ork ag)-3.055 F 2.955(ain. The)-.05 F -.15(ex)
2.955 G .455(pression is interpreted as a list of single characters \(h)
.15 F .455(yphens allo)-.05 F .455(wed for)-.25 F 2.761(ranges\). All)
128 436.8 R -.25(va)2.761 G .261(riables and arrays be).25 F .26
(ginning with one of those letters are reset to their pristine state.)
-.15 F(If)5.26 E 1.192(the e)128 448.8 R 1.192
(xpression is omitted, one-match searches \()-.15 F F1(?pattern?)A F0
3.692(\)a)C 1.192(re reset to match ag)-3.692 F 3.693(ain. Only)-.05 F
(resets)3.693 E -.25(va)128 460.8 S
(riables or searches in the current package.).25 E(Al)5 E -.1(wa)-.1 G
(ys returns 1.).1 E(Examples:)5 E F1(reset \010X\010;)152 478.8 Q 6(#r)
36 G(eset all X variables)-6 E(reset \010a\255z\010;)152 490.8 Q 6(#r)24
G(eset lower case variables)-6 E 54(reset; #)152 502.8 R
(just reset ?one\255time? searches)6 E F0(Resetting)128 520.8 Q F1
("A\255Z")3.916 E F0 1.416(is not recommended because you')3.916 F 1.416
(ll wipe out your)-.1 F F1(@ARGV)3.916 E F0(and)3.915 E F1(@INC)3.915 E
F0 1.415(arrays and)3.915 F(your)128 532.8 Q F1(%ENV)4.714 E F0 4.714
(hash. Resets)4.714 F 2.214(only package v)4.714 F 2.215(ariables; le)
-.25 F 2.215(xical v)-.15 F 2.215(ariables are unaf)-.25 F 2.215
(fected, b)-.25 F 2.215(ut the)-.2 F 4.715(yc)-.15 G(lean)-4.715 E
(themselv)128 544.8 Q(es up on scope e)-.15 E(xit an)-.15 E(yw)-.15 E
(ay)-.1 E 2.5(,s)-.65 G 2.5(oy)-2.5 G(ou')-2.5 E(ll probably w)-.1 E
(ant to use them instead.)-.1 E(See `)5 E(`my')-.74 E('.)-.74 E(return)
108 561.6 Q F2(EXPR)2.5 E F0(return)108 573.6 Q .909
(Returns from a subroutine,)128 585.6 R F1(eval)3.409 E F0 3.408(,o)C(r)
-3.408 E F1 .908(do FILE)3.408 F F0 .908(with the v)3.408 F .908
(alue gi)-.25 F -.15(ve)-.25 G 3.408(ni).15 G(n)-3.408 E F2(EXPR)3.408 E
F0 5.908(.E)C -.25(va)-5.908 G .908(luation of).25 F F2(EXPR)3.408 E F0
.225(may be in list, scalar)128 597.6 R 2.726(,o)-.4 G 2.726(rv)-2.726 G
.226(oid conte)-2.926 F .226(xt, depending on ho)-.15 F 2.726(wt)-.25 G
.226(he return v)-2.726 F .226(alue will be used, and the conte)-.25 F
(xt)-.15 E .82(may v)128 609.6 R .82(ary from one e)-.25 F -.15(xe)-.15
G .82(cution to the ne).15 F .82(xt \(see)-.15 F F1(wantarray)3.32 E F0
3.32(\). If)B(no)3.32 E F2(EXPR)3.32 E F0 .819(is gi)3.32 F -.15(ve)-.25
G .819(n, returns an empty).15 F(list in list conte)128 621.6 Q
(xt, the unde\214ned v)-.15 E(alue in scalar conte)-.25 E
(xt, and \(of course\) nothing at all in v)-.15 E(oid conte)-.2 E(xt.)
-.15 E .585(\(In the absence of an e)128 639.6 R(xplicit)-.15 E F1
(return)3.085 E F0 3.085(,as)C .585(ubroutine, e)-3.085 F -.25(va)-.25 G
.585(l, or do).25 F F2(FILE)3.085 E F0 .585(automatically returns the v)
3.085 F(alue)-.25 E(of the last e)128 651.6 Q(xpression e)-.15 E -.25
(va)-.25 G(luated.\)).25 E(re)108 668.4 Q -.15(ve)-.25 G(rse).15 E F2
(LIST)2.5 E F0 .763(In list conte)128 680.4 R .763(xt, returns a list v)
-.15 F .762(alue consisting of the elements of)-.25 F F2(LIST)3.262 E F0
.762(in the opposite order)3.262 F 5.762(.I)-.55 G 3.262(ns)-5.762 G
(calar)-3.262 E(conte)128 692.4 Q .061(xt, concatenates the elements of)
-.15 F F2(LIST)2.561 E F0 .061(and returns a string v)2.561 F .062
(alue with all characters in the opposite)-.25 F(order)128 704.4 Q(.)
-.55 E(perl v5.14.2)72 768 Q 198.17(2011-10-01 65)162.62 F 0 Cg EP
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/F0 10/Times-Roman@0 SF 92.855(PERLFUNC\(1\) User)72 48 R(Contrib)2.5 E
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(print join\(", ", reverse "world", "Hello"\); # Hello, world)152 84 Q
(print scalar reverse "dlrow ,", "olleH";)152 108 Q 6(#H)24 G
(ello, world)-6 E F0(Used without ar)128 126 Q(guments in scalar conte)
-.18 E(xt,)-.15 E/F2 10/Times-Italic@0 SF -1.91 -.37(re v)2.5 H(er).37 E
(se\(\))-.1 E F0(re)2.5 E -.15(ve)-.25 G(rses).15 E F1($_)2.5 E F0(.)A
F1($_ = "dlrow ,olleH";)152 144 Q(print reverse;)152 156 Q 6(#N)180 G 6
(oo)-6 G(utput, list context)-6 E(print scalar reverse;)152 168 Q 6(#H)
138 G(ello, world)-6 E F0 .225(Note that re)128 186 R -.15(ve)-.25 G
.225(rsing an array to itself \(as in).15 F F1 .225(@a = reverse @a)
2.725 F F0 2.725(\)w)C .225(ill preserv)-2.725 F 2.725(en)-.15 G(on-e)
-2.725 E .225(xistent elements)-.15 F(whene)128 198 Q -.15(ve)-.25 G 2.5
(rp).15 G(ossible, i.e., for non magical arrays or tied arrays with)-2.5
E F1(EXISTS)2.5 E F0(and)2.5 E F1(DELETE)2.5 E F0(methods.)2.5 E 2.183
(This operator is also handy for in)128 216 R -.15(ve)-.4 G 2.184
(rting a hash, although there are some ca).15 F -.15(ve)-.2 G 4.684
(ats. If).15 F 4.684(av)4.684 G 2.184(alue is)-4.934 F 1.24(duplicated \
in the original hash, only one of those can be represented as a k)128
228 R 1.54 -.15(ey i)-.1 H 3.74(nt).15 G 1.24(he in)-3.74 F -.15(ve)-.4
G 1.24(rted hash.).15 F .694(Also, this has to unwind one hash and b)128
240 R .694(uild a whole ne)-.2 F 3.195(wo)-.25 G .695(ne, which may tak)
-3.195 F 3.195(es)-.1 G .695(ome time on a lar)-3.195 F(ge)-.18 E
(hash, such as from a)128 252 Q/F3 9/Times-Roman@0 SF(DBM)2.5 E F0
(\214le.)2.5 E F1(%by_name = reverse %by_address;)152 270 Q 6(#I)12 G
(nvert the hash)-6 E F0(re)108 286.8 Q(winddir)-.25 E F3(DIRHANDLE)2.5 E
F0(Sets the current position to the be)128 298.8 Q
(ginning of the directory for the)-.15 E F1(readdir)2.5 E F0(routine on)
2.5 E F3(DIRHANDLE)2.5 E F0(.)A(rinde)108 315.6 Q(x)-.15 E F3(STR)2.5 E
F0(,SUBSTR,POSITION)A(rinde)108 327.6 Q(x)-.15 E F3(STR)2.5 E F0
(,SUBSTR)A -.8(Wo)128 339.6 S .433(rks just lik).8 F(e)-.1 E F2(inde)
2.933 E(x\(\))-.2 E F0 -.15(ex)2.933 G .433
(cept that it returns the position of the).15 F F2(last)2.933 E F0 .433
(occurrence of)2.933 F F3(SUBSTR)2.933 E F0(in)2.933 E F3(STR)2.933 E F0
5.432(.I)C(f)-5.432 E F3(POSITION)128 351.6 Q F0
(is speci\214ed, returns the last occurrence be)2.5 E
(ginning at or before that position.)-.15 E(rmdir)108 368.4 Q F3(FILEN)
2.5 E(AME)-.315 E F0(rmdir)108 380.4 Q .644
(Deletes the directory speci\214ed by)128 392.4 R F3(FILEN)3.144 E(AME)
-.315 E F0 .644(if that directory is empty)3.144 F 5.645(.I)-.65 G 3.145
(fi)-5.645 G 3.145(ts)-3.145 G .645(ucceeds it returns true;)-3.145 F
(otherwise it returns f)128 404.4 Q(alse and sets)-.1 E F1($!)2.5 E F0
2.5(\(errno\). If)2.5 F F3(FILEN)2.5 E(AME)-.315 E F0(is omitted, uses)
2.5 E F1($_)2.5 E F0(.)A 3.799 -.8(To r)128 422.4 T(emo).8 E 2.499 -.15
(ve a d)-.15 H 2.199(irectory tree recursi).15 F -.15(ve)-.25 G 2.199
(ly \().15 F F1 2.199(rm \255rf)B F0 2.199(on Unix\) look at the)4.699 F
F1(rmtree)4.698 E F0 2.198(function of the)4.698 F(File::P)128 434.4 Q
(ath module.)-.15 E(s///)108 451.2 Q(The substitution operator)128 451.2
Q 5(.S)-.55 G(ee `)-5 E(`Re)-.74 E(ge)-.15 E(xp Quote-Lik)-.15 E 2.5(eO)
-.1 G(perators')-2.5 E 2.5('i)-.74 G 2.5(np)-2.5 G(erlop.)-2.5 E(say)108
468 Q F3 .25(FILEHANDLE LIST)2.5 F F0(say)108 480 Q F3(FILEHANDLE)2.5 E
F0(say)108 492 Q F3(LIST)2.5 E F0(say)108 504 Q 2.013(Just lik)128 504 R
(e)-.1 E F1(print)4.513 E F0 4.513(,b)C 2.013
(ut implicitly appends a ne)-4.713 F(wline.)-.25 E F1 2.013(say LIST)
7.013 F F0 2.014(is simply an abbre)4.513 F 2.014(viation for)-.25 F F1
({)4.514 E .135(local $\\ = "\\n"; print LIST })128 516 R F0 5.135(.T)C
2.635(ou)-5.935 G(se)-2.635 E F3(FILEHANDLE)2.634 E F0 .134(without a)
2.634 F F3(LIST)2.634 E F0 .134(to print the contents)2.634 F(of)128 528
Q F1($_)2.5 E F0(to it, you must use a real \214lehandle lik)2.5 E(e)-.1
E F1(FH)2.5 E F0 2.5(,n)C(ot an indirect one lik)-2.5 E(e)-.1 E F1($fh)
2.5 E F0(.)A .236(This k)128 546 R -.15(ey)-.1 G -.1(wo).15 G .236
(rd is a).1 F -.25(va)-.2 G .236(ilable only when the).25 F F1("say")
2.736 E F0 .236(feature is enabled; see feature.)2.736 F(Alternately)
5.236 E 2.736(,i)-.65 G .236(nclude a)-2.736 F F1(use v5.10)128 558 Q F0
(or later to the current scope.)2.5 E(scalar)108 574.8 Q F3(EXPR)2.5 E
F0 -.15(Fo)128 586.8 S(rces).15 E F3(EXPR)2.5 E F0
(to be interpreted in scalar conte)2.5 E(xt and returns the v)-.15 E
(alue of)-.25 E F3(EXPR)2.5 E F0(.)A F1
(@counts = \( scalar @a, scalar @b, scalar @c \);)152 604.8 Q F0 1.465
(There is no equi)128 622.8 R -.25(va)-.25 G 1.465
(lent operator to force an e).25 F 1.464
(xpression to be interpolated in list conte)-.15 F 1.464(xt because in)
-.15 F .507(practice, this is ne)128 634.8 R -.15(ve)-.25 G 3.007(rn).15
G 3.007(eeded. If)-3.007 F .508(you really w)3.007 F .508
(anted to do so, ho)-.1 F(we)-.25 E -.15(ve)-.25 G 1.308 -.4(r, y).15 H
.508(ou could use the construction).4 F F1(@{[ \(some expression\) ]})
128 646.8 Q F0 2.5(,b)C(ut usually a simple)-2.7 E F1
(\(some expression\))2.5 E F0(suf)2.5 E(\214ces.)-.25 E(Because)128
664.8 Q F1(scalar)3.446 E F0 .946(is a unary operator)3.446 F 3.446(,i)
-.4 G 3.446(fy)-3.446 G .946
(ou accidentally use a parenthesized list for the)-3.446 F F3(EXPR)3.446
E F0 3.446(,t)C(his)-3.446 E(beha)128 676.8 Q -.15(ve)-.2 G 2.639(sa).15
G 2.639(sas)-2.639 G .139(calar comma e)-2.639 F .139(xpression, e)-.15
F -.25(va)-.25 G .139(luating all b).25 F .14(ut the last element in v)
-.2 F .14(oid conte)-.2 F .14(xt and returning)-.15 F
(the \214nal element e)128 688.8 Q -.25(va)-.25 G
(luated in scalar conte).25 E 2.5(xt. This)-.15 F(is seldom what you w)
2.5 E(ant.)-.1 E(The follo)128 706.8 Q(wing single statement:)-.25 E
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(print uc\(scalar\(&foo,$bar\)\),$baz;)152 84 Q F0(is the moral equi)128
102 Q -.25(va)-.25 G(lent of these tw).25 E(o:)-.1 E F1(&foo;)152 120 Q
(print\(uc\($bar\),$baz\);)152 132 Q F0
(See perlop for more details on unary operators and the comma operator)
128 150 Q(.)-.55 E(seek)108 166.8 Q/F2 9/Times-Roman@0 SF(FILEHANDLE)2.5
E F0(,POSITION,WHENCE)A(Sets)128 178.8 Q F2(FILEHANDLE)5.886 E F0 4.486
-.55('s p)D 3.386(osition, just lik).55 F 5.886(et)-.1 G(he)-5.886 E F1
(fseek)5.886 E F0 3.385(call of)5.886 F F1(stdio)5.885 E F0(.)A F2
(FILEHANDLE)8.385 E F0 3.385(may be an)5.885 F -.15(ex)128 190.8 S .061
(pression whose v).15 F .061(alue gi)-.25 F -.15(ve)-.25 G 2.561(st).15
G .061(he name of the \214lehandle.)-2.561 F .062(The v)5.061 F .062
(alues for)-.25 F F2(WHENCE)2.562 E F0(are)2.562 E F1(0)2.562 E F0 .062
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E F0(;)A F1(1)2.799 E F0 .299(to set it to the current position plus)
2.799 F F2(POSITION)2.798 E F0 2.798(;a)C(nd)-2.798 E F1(2)2.798 E F0
.298(to set it to)2.798 F F2(EOF)2.798 E F0(plus)128 214.8 Q F2
(POSITION)2.527 E F0 2.527(,t)C .027(ypically ne)-2.527 F -.05(ga)-.15 G
(ti).05 E -.15(ve)-.25 G 5.027(.F).15 G(or)-5.177 E F2(WHENCE)2.528 E F0
.028(you may use the constants)2.528 F F1(SEEK_SET)2.528 E F0(,)A F1
(SEEK_CUR)2.528 E F0(,)A(and)128 226.8 Q F1(SEEK_END)3.218 E F0 .718(\(\
start of the \214le, current position, end of the \214le\) from the Fcn\
tl module.)3.218 F(Returns)5.717 E F1(1)3.217 E F0(on success, f)128
238.8 Q(alse otherwise.)-.1 E .095(Note the)128 256.8 R F3 .095
(in bytes)2.595 F F0 2.595(:e)C -.15(ve)-2.845 G 2.595(ni).15 G 2.595
(ft)-2.595 G .095
(he \214lehandle has been set to operate on characters \(for e)-2.595 F
.096(xample by using the)-.15 F F1(:encoding\(utf8\))128 268.8 Q F0
3.039(open layer\),)5.539 F F3(tell\(\))5.538 E F0 3.038
(will return byte of)5.538 F 3.038(fsets, not character of)-.25 F 3.038
(fsets \(because)-.25 F(implementing that w)128 280.8 Q(ould render)-.1
E F3(seek\(\))2.5 E F0(and)2.5 E F3(tell\(\))2.5 E F0(rather slo)2.5 E
(w\).)-.25 E 1.788(If you w)128 298.8 R 1.788
(ant to position the \214le for)-.1 F F1(sysread)4.289 E F0(or)4.289 E
F1(syswrite)4.289 E F0 4.289(,d)C(on')-4.289 E 4.289(tu)-.18 G(se)-4.289
E F1(seek)4.289 E F0 4.289(,b)C 1.789(ecause b)-4.289 F(uf)-.2 E(fering)
-.25 E(mak)128 310.8 Q 2.257(es its ef)-.1 F 2.257(fect on the \214le')
-.25 F 4.757(sr)-.55 G 2.257
(ead-write position unpredictable and non-portable.)-4.757 F(Use)7.256 E
F1(sysseek)4.756 E F0(instead.)128 322.8 Q .687
(Due to the rules and rigors of)128 340.8 R F2(ANSI)3.187 E F0 .688
(C, on some systems you ha)3.188 F .988 -.15(ve t)-.2 H 3.188(od).15 G
3.188(oas)-3.188 G .688(eek whene)-3.188 F -.15(ve)-.25 G 3.188(ry).15 G
.688(ou switch)-3.188 F 2.471(between reading and writing.)128 352.8 R
2.471(Amongst other things, this may ha)7.471 F 2.771 -.15(ve t)-.2 H
2.47(he ef).15 F 2.47(fect of calling stdio')-.25 F(s)-.55 E F3(clear)
128 364.8 Q(err)-.37 E F0 2.5(\(3\). A)1.666 F F2(WHENCE)2.5 E F0(of)2.5
E F1(1)2.5 E F0(\()2.5 E F1(SEEK_CUR)A F0 2.5(\)i)C 2.5(su)-2.5 G
(seful for not mo)-2.5 E(ving the \214le position:)-.15 E F1
(seek\(TEST,0,1\);)152 382.8 Q F0 1.126
(This is also useful for applications emulating)128 400.8 R F1 1.126
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(If that doesn')128 454.8 R 5.181(tw)-.18 G 2.681
(ork \(some I/O implementations are particularly cantank)-5.281 F 2.68
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(his:)-2.5 E F1(for \(;;\) {)152 484.8 Q
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($curpos = tell\(FILE\)\) {)206 508.8 Q 6(#s)200 520.8 S
(earch for some stuff and put it into files)-6 E(})176 532.8 Q
(sleep\($for_a_while\);)176 544.8 Q(seek\(FILE, $curpos, 0\);)176 556.8
Q(})152 568.8 Q F0(seekdir)108 585.6 Q F2(DIRHANDLE)2.5 E F0(,POS)A .393
(Sets the current position for the)128 597.6 R F1(readdir)2.893 E F0
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F0(select)108 232.8 Q F2(RBITS)2.5 E F0(,WBITS,EBITS,TIMEOUT)A .514
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(vec\($win,fileno\(STDOUT\),1\) = 1;)152 298.8 Q($ein = $rin | $win;)152
310.8 Q F0(If you w)128 328.8 Q(ant to select on man)-.1 E 2.5<798c>-.15
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(his:)-2.5 E F1(sub fhbits {)152 346.8 Q
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370.8 Q(for \(@fhlist\) {)176 382.8 Q(vec\($bits,fileno\($_\),1\) = 1;)
200 394.8 Q(})176 406.8 Q($bits;)176 418.8 Q(})152 430.8 Q
($rin = fhbits\(\010STDIN TTY SOCK\010\);)152 442.8 Q F0
(The usual idiom is:)128 460.8 Q F1(\($nfound,$timeleft\) =)152 478.8 Q
(select\($rout=$rin, $wout=$win, $eout=$ein, $timeout\);)164 490.8 Q F0
(or to block until something becomes ready just do this)128 508.8 Q F1
($nfound = select\($rout=$rin, $wout=$win, $eout=$ein, undef\);)152
526.8 Q F0 1.472(Most systems do not bother to return an)128 544.8 R
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(An)128 574.8 Q 4.396(yo)-.15 G 4.396(ft)-4.396 G 1.896
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(fractional. Note:)128 586.8 R 2.042
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(Note that whether)128 652.8 R F1(select)3.09 E F0 .59
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(See also perlport for notes on the portability of)128 664.8 Q F1
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(beha)2.5 E -.15(ve)-.2 G 2.5(sl).15 G(ik)-2.5 E(e)-.1 E F3(select)2.5 E
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(\214rst to get the correct constant de\214nitions.)128 160.8 R(If)6.521
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(\(2\) for semaphore operations such as signalling and w)1.666 F
(aiting.)-.1 E F3(OPSTRING)128 302.4 Q F0 .602(must be a pack)3.102 F
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(Each semop structure can be generated with)5.602 F F2 3.272
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368.4 Q F0 3.303 -.8(To s)128 386.4 T 1.703
(ignal the semaphore, replace).8 F F2<ad31>4.204 E F0(with)4.204 E F2(1)
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6.223 F .123(sent, or the unde\214ned v)128 475.2 R .123(alue on error)
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505.2 R F4 -.15(ch)3.039 G(ar).15 E(acter)-.15 E(s)-.1 E F0 3.038(:d)C
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(By def)128 517.2 R 2.583(ault all sock)-.1 F 2.583
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(binmode\(\))128 529.2 Q F0 1.612(to operate with the)4.112 F F2
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(Similarly for the)7.456 F F2(:encoding)128 553.2 Q F0
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F3(WHICH)2.5 E F0(,WHO,PRIORITY)A 1.588
(Sets the current priority for a process, a process group, or a user)128
646.8 R 6.589(.\()-.55 G(See)-6.589 E F4(setpriority)4.089 E F0 4.089
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3.115 E({})128 214.8 Q F0(,)A F1(CHECK {})2.5 E F0(,)A F1(UNITCHECK {})
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3.223 F -.15(ex)128 256.8 S 2.5(perimental. The).15 F -.15(ex)2.5 G
(act beha).15 E(viour may change in a future v)-.2 E(ersion of Perl.)
-.15 E .705(See also)128 274.8 R F1(unshift)3.205 E F0(,)A F1(push)3.205
E F0 3.205(,a)C(nd)-3.205 E F1(pop)3.205 E F0(.)A F1(shift)5.705 E F0
(and)3.205 E F1(unshift)3.205 E F0 .706
(do the same thing to the left end of an)3.206 F(array that)128 286.8 Q
F1(pop)2.5 E F0(and)2.5 E F1(push)2.5 E F0(do to the right end.)2.5 E
(shmctl)108 303.6 Q F2(ID)2.5 E F0(,CMD,ARG)A(Calls the System V)128
315.6 Q F2(IPC)2.5 E F0(function shmctl.)2.5 E -1.1(Yo)5 G(u')1.1 E
(ll probably ha)-.1 E .3 -.15(ve t)-.2 H 2.5(os).15 G(ay)-2.5 E F1
(use IPC::SysV;)152 333.6 Q F0 .739
(\214rst to get the correct constant de\214nitions.)128 351.6 R(If)5.739
E F2(CMD)3.239 E F0(is)3.239 E F1(IPC_STAT)3.239 E F0 3.239(,t)C(hen)
-3.239 E F2(ARG)3.239 E F0 .738(must be a v)3.239 F .738(ariable that)
-.25 F .046(will hold the returned)128 363.6 R F1(shmid_ds)2.547 E F0
2.547(structure. Returns)2.547 F(lik)2.547 E 2.547(ei)-.1 G(octl:)-2.547
E F1(undef)2.547 E F0 .047(for error; ")2.547 F F1(0)A F0 -.2(bu)2.547 G
2.547(tt).2 G .047(rue" for zero;)-2.547 F 4.442
(and the actual return v)128 375.6 R 4.441(alue otherwise.)-.25 F 4.441
(See also `)9.441 F(`SysV)-.74 E F2(IPC)6.941 E F0 5.921 -.74('' i)D
6.941(np).74 G 4.441(erlipc and)-6.941 F F1(IPC::SysV)6.941 E F0
(documentation.)128 387.6 Q(shmget)108 404.4 Q F2(KEY)2.5 E F0
(,SIZE,FLA)A(GS)-.4 E .337(Calls the System V)128 416.4 R F2(IPC)2.837 E
F0 .337(function shmget.)2.837 F .337(Returns the shared memory se)5.337
F .337(gment id, or)-.15 F F1(undef)2.838 E F0 .338(on error)2.838 F(.)
-.55 E(See also `)128 428.4 Q(`SysV)-.74 E F2(IPC)2.5 E F0 1.48 -.74
('' i)D 2.5(np).74 G(erlipc and)-2.5 E F1(IPC::SysV)2.5 E F0
(documentation.)2.5 E(shmread)108 445.2 Q F2(ID)2.5 E F0(,V)A
(AR,POS,SIZE)-1.35 E(shmwrite)108 457.2 Q F2(ID)2.5 E F0
(,STRING,POS,SIZE)A 1.126(Reads or writes the System V shared memory se)
128 469.2 R(gment)-.15 E F2(ID)3.625 E F0 1.125(starting at position)
3.625 F F2(POS)3.625 E F0 1.125(for size)3.625 F F2(SIZE)3.625 E F0(by)
3.625 E .336(attaching to it, cop)128 481.2 R .336
(ying in/out, and detaching from it.)-.1 F .336(When reading,)5.336 F F2
-1.215(VA)2.836 G(R)1.215 E F0 .337(must be a v)2.836 F .337
(ariable that will)-.25 F .672(hold the data read.)128 493.2 R .671
(When writing, if)5.672 F F2(STRING)3.171 E F0 .671(is too long, only)
3.171 F F2(SIZE)3.171 E F0 .671(bytes are used; if)3.171 F F2(STRING)
3.171 E F0 .671(is too)3.171 F .157
(short, nulls are written to \214ll out)128 505.2 R F2(SIZE)2.658 E F0
2.658(bytes. Return)2.658 F .158(true if successful, f)2.658 F .158
(alse on error)-.1 F(.)-.55 E/F3 10/Times-Italic@0 SF(shmr)5.158 E
(ead\(\))-.37 E F0(taints)2.658 E .009(the v)128 517.2 R .008
(ariable. See also `)-.25 F(`SysV)-.74 E F2(IPC)2.508 E F0 1.488 -.74
('' i)D 2.508(np).74 G(erlipc,)-2.508 E F1(IPC::SysV)2.508 E F0 2.508
(,a)C .008(nd the)-2.508 F F1(IPC::Shareable)2.508 E F0 .008
(module from)2.508 F F2(CP)128 529.2 Q(AN)-.828 E F0(.)A(shutdo)108 546
Q(wn)-.25 E F2(SOCKET)2.5 E F0(,HO)A(W)-.35 E .059(Shuts do)128 558 R
.059(wn a sock)-.25 F .059(et connection in the manner indicated by)-.1
F F2(HO)2.56 E(W)-.315 E F0 2.56(,w)C .06
(hich has the same interpretation as)-2.56 F
(in the syscall of the same name.)128 570 Q F1(shutdown\(SOCKET, 0\);)
152 588 Q 6(#I)24 G(/we have stopped reading data)-6 E
(shutdown\(SOCKET, 1\);)152 600 Q 6(#I)24 G
(/we have stopped writing data)-6 E(shutdown\(SOCKET, 2\);)152 612 Q 6
(#I)24 G(/we have stopped using this socket)-6 E F0 1.49
(This is useful with sock)128 630 R 1.49(ets when you w)-.1 F 1.49
(ant to tell the other side you')-.1 F 1.49(re done writing b)-.5 F 1.49
(ut not done)-.2 F 2.352(reading, or vice v)128 642 R 4.852(ersa. It')
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(lso a more insistent form of close because it also disables the \214le)
-4.852 F(descriptor in an)128 654 Q 2.5(yf)-.15 G(ork)-2.5 E
(ed copies in other processes.)-.1 E(Returns)128 672 Q F1(1)2.667 E F0
.167(for success; on error)2.667 F 2.667(,r)-.4 G(eturns)-2.667 E F1
(undef)2.667 E F0 .167(if the \214rst ar)2.667 F .166(gument is not a v)
-.18 F .166(alid \214lehandle, or returns)-.25 F F1(0)128 684 Q F0
(and sets)2.5 E F1($!)2.5 E F0(for an)2.5 E 2.5(yo)-.15 G(ther f)-2.5 E
(ailure.)-.1 E(sin)108 700.8 Q F2(EXPR)2.5 E F0(sin)108 712.8 Q
(Returns the sine of)128 712.8 Q F2(EXPR)2.5 E F0(\(e)2.5 E
(xpressed in radians\).)-.15 E(If)5 E F2(EXPR)2.5 E F0
(is omitted, returns sine of)2.5 E F1($_)2.5 E F0(.)A -.15(Fo)128 730.8
S 2.5(rt).15 G(he in)-2.5 E -.15(ve)-.4 G
(rse sine operation, you may use the).15 E F1(Math::Trig::asin)2.5 E F0
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128 136.8 Q(ger number of seconds actually slept.)-.15 E
(May be interrupted if the process recei)128 154.8 Q -.15(ve)-.25 G 2.5
(sas).15 G(ignal such as)-2.5 E F1(SIGALRM)2.5 E F0(.)A F1(eval {)152
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F0 -1.1(Yo)128 238.8 S 4.622(up)1.1 G 2.122(robably cannot mix)-4.622 F
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5.131 F -.1(wa)-.1 G .131(ys sleep the full amount.).1 F(The)5.13 E 2.63
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292.8 R(we)-.25 E -.15(ve)-.25 G 3.612 -.4(r, b).15 H 2.812
(ecause your process might not be scheduled right a).4 F -.1(wa)-.15 G
5.312(yi).1 G 5.312(nab)-5.312 G(usy)-5.512 E(multitasking system.)128
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(ime::HiRes module \(from)-.35 F F2(CP)3.844 E(AN)-.828 E F0 3.844(,a)C
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(our)-4.525 E(-)-.2 E(ar)128 346.8 Q .816(gument v)-.18 F .816
(ersion of)-.15 F F3(select\(\))3.316 E F0(lea)3.316 E .816
(ving the \214rst three ar)-.2 F .815
(guments unde\214ned, or you might be able to use)-.18 F(the)128 358.8 Q
F1(syscall)2.5 E F0(interf)2.5 E(ace to access)-.1 E F3(setitimer)2.5 E
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-.1 E(See also the)128 376.8 Q F2(POSIX)2.5 E F0(module')2.5 E(s)-.55 E
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2.5 E F0(,DOMAIN,TYPE,PR)A -1.88 -.4(OT O)-.4 H(COL).4 E 1.787
(Opens a sock)128 405.6 R 1.788
(et of the speci\214ed kind and attaches it to \214lehandle)-.1 F F2
(SOCKET)4.288 E F0(.)A F2(DOMAIN)6.788 E F0(,)A F2(TYPE)4.288 E F0 4.288
(,a)C(nd)-4.288 E F2(PR)128 417.6 Q -1.692 -.36(OT O)-.36 H(COL).36 E F0
1.086(are speci\214ed the same as for the syscall of the same name.)
3.586 F -1.1(Yo)6.085 G 3.585(us)1.1 G(hould)-3.585 E F1 1.085
(use Socket)3.585 F F0 4.986
(\214rst to get the proper de\214nitions imported.)128 429.6 R 4.986
(See the e)9.986 F 4.986(xamples in `)-.15 F(`Sock)-.74 E 4.986
(ets: Client/Serv)-.1 F(er)-.15 E(Communication')128 441.6 Q 2.5('i)-.74
G 2.5(np)-2.5 G(erlipc.)-2.5 E 1.179
(On systems that support a close-on-e)128 459.6 R -.15(xe)-.15 G 3.679
<638d>.15 G 1.178(ag on \214les, the \215ag will be set for the ne)
-3.679 F 1.178(wly opened \214le)-.25 F(descriptor)128 471.6 Q 2.5(,a)
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-.8 G(ee `)-5 E(`$^F')-.74 E 2.5('i)-.74 G 2.5(np)-2.5 G(erlv)-2.5 E(ar)
-.25 E(.)-.55 E(sock)108 488.4 Q(etpair)-.1 E F2(SOCKET1)2.5 E F0
(,SOCKET2,DOMAIN,TYPE,PR)A -1.88 -.4(OT O)-.4 H(COL).4 E .955
(Creates an unnamed pair of sock)128 500.4 R .955
(ets in the speci\214ed domain, of the speci\214ed type.)-.1 F F2
(DOMAIN)5.956 E F0(,)A F2(TYPE)3.456 E F0(,)A(and)128 512.4 Q F2(PR)
3.067 E -1.692 -.36(OT O)-.36 H(COL).36 E F0 .567
(are speci\214ed the same as for the syscall of the same name.)3.067 F
.566(If unimplemented, raises)5.567 F(an e)128 524.4 Q 2.5
(xception. Returns)-.15 F(true if successful.)2.5 E 1.178
(On systems that support a close-on-e)128 542.4 R -.15(xe)-.15 G 3.678
<638d>.15 G 1.178(ag on \214les, the \215ag will be set for the ne)
-3.678 F 1.179(wly opened \214le)-.25 F
(descriptors, as determined by the v)128 554.4 Q(alue of $^F)-.25 E 5
(.S)-.8 G(ee `)-5 E(`$^F')-.74 E 2.5('i)-.74 G 2.5(np)-2.5 G(erlv)-2.5 E
(ar)-.25 E(.)-.55 E 1.249(Some systems de\214ned)128 572.4 R F1(pipe)
3.749 E F0 1.249(in terms of)3.749 F F1(socketpair)3.749 E F0 3.749(,i)C
3.749(nw)-3.749 G 1.248(hich a call to)-3.749 F F1 1.248
(pipe\(Rdr, Wtr\))3.748 F F0(is)3.748 E(essentially:)128 584.4 Q F1
(use Socket;)152 602.4 Q
(socketpair\(Rdr, Wtr, AF_UNIX, SOCK_STREAM, PF_UNSPEC\);)152 614.4 Q
(shutdown\(Rdr, 1\);)152 626.4 Q 6(#n)48 G 6(om)-6 G
(ore writing for reader)-6 E(shutdown\(Wtr, 0\);)152 638.4 Q 6(#n)48 G 6
(om)-6 G(ore reading for writer)-6 E F0 1.786(See perlipc for an e)128
656.4 R 1.787(xample of sock)-.15 F 1.787(etpair use.)-.1 F 1.787
(Perl 5.8 and later will emulate sock)6.787 F 1.787(etpair using)-.1 F
F2(IP)4.287 E F0(sock)128 668.4 Q
(ets to localhost if your system implements sock)-.1 E(ets b)-.1 E
(ut not sock)-.2 E(etpair)-.1 E(.)-.55 E(sort)108 685.2 Q F2(SUBN)2.5 E
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138 R -.15(ve)-.25 G 2.659(st).15 G .159
(he name of a subroutine that returns an inte)-2.659 F .158
(ger less than, equal to, or greater than)-.15 F F2(0)2.658 E F0(,)A
2.153(depending on ho)128 150 R 4.653(wt)-.25 G 2.153
(he elements of the list are to be ordered.)-4.653 F(\(The)7.154 E F2
(<=>)4.654 E F0(and)4.654 E F2(cmp)4.654 E F0 2.154(operators are)4.654
F -.15(ex)128 162 S 1.873(tremely useful in such routines.\)).15 F F1
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(ariable name \(unsubscripted\), in)-.25 F .322(which case the v)128 174
R .322(alue pro)-.25 F .323
(vides the name of \(or a reference to\) the actual subroutine to use.)
-.15 F .323(In place of)5.323 F(a)128 186 Q F1(SUBN)2.5 E(AME)-.315 E F0
2.5(,y)C(ou can pro)-2.5 E(vide a)-.15 E F1(BLOCK)2.5 E F0(as an anon)
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204 R 3.038(sp)-.55 G .538(rototype is)-3.038 F F2(\($$\))3.038 E F0
3.038(,t)C .538(he elements to be compared are passed by reference in)
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(for a normal subroutine.)128 216 R 1.851(This is slo)6.85 F 1.851
(wer than unprototyped subroutines, where the elements to be)-.25 F
1.585(compared are passed into the subroutine as the package global v)
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1.584(\(see e)4.084 F(xample)-.15 E(belo)128 240 Q 3.481(w\). Note)-.25
F .982(that in the latter case, it is usually highly counter)3.481 F
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F2($a)3.482 E F0(and)3.482 E F2($b)3.482 E F0(as)3.482 E(le)128 252 Q
(xicals.)-.15 E(The v)128 270 Q(alues to be compared are al)-.25 E -.1
(wa)-.1 G(ys passed by reference and should not be modi\214ed.).1 E -1.1
(Yo)128 288 S 4.549(ua)1.1 G 2.049(lso cannot e)-4.549 F 2.049
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318 Q F2 1.009(use locale)3.509 F F0 1.009(is in ef)3.509 F(fect,)-.25 E
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(according to the current collation locale.)3.51 F(See perllocale.)128
330 Q/F3 10/Times-Italic@0 SF(sort\(\))128 348 Q F0 .291
(returns aliases into the original list, much as a for loop')2.791 F
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(ariable aliases the list elements.)-3.04 F .255
(That is, modifying an element of a list returned by)128 360 R F3
(sort\(\))2.755 E F0 .255(\(for e)2.755 F .255(xample, in a)-.15 F F2
(foreach)2.755 E F0(,)A F2(map)2.755 E F0(or)2.755 E F2(grep)2.755 E F0
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372 R 2.068(This is usually something to be a)7.068 F -.2(vo)-.2 G 2.068
(ided when).2 F(writing clear code.)128 384 Q .862
(Perl 5.6 and earlier used a quicksort algorithm to implement sort.)128
402 R .863(That algorithm w)5.863 F .863(as not stable, so)-.1 F F3
(could)128 414 Q F0 .093(go quadratic.)2.593 F(\(A)5.093 E F3(stable)
2.593 E F0 .093(sort preserv)2.593 F .093
(es the input order of elements that compare equal.)-.15 F(Although)
5.092 E(quicksort')128 426 Q 2.644(sr)-.55 G .144
(un time is O\(NlogN\) when a)-2.644 F -.15(ve)-.2 G .145(raged o).15 F
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438 Q(atic)-.15 E F0(beha)2.886 E(vior)-.2 E 2.886(,f)-.4 G .386
(or some inputs.\))-2.886 F .386(In 5.7, the quicksort implementation w)
5.386 F .385(as replaced with a stable)-.1 F(mer)128 450 Q .027
(gesort algorithm whose w)-.18 F .027(orst-case beha)-.1 F .027
(vior is O\(NlogN\).)-.2 F .028(But benchmarks indicated that for some)
5.028 F .435(inputs, on some platforms, the original quicksort w)128 462
R .435(as f)-.1 F(aster)-.1 E 5.435(.5)-.55 G .435
(.8 has a sort pragma for limited control)-5.435 F .784(of the sort.)128
474 R .785(Its rather blunt control of the underlying algorithm may not\
 persist into future Perls, b)5.784 F(ut)-.2 E .212(the ability to char\
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.212(ays quite probably will.)-.1 F(See the sort pragma.)128 498 Q
(Examples:)128 516 Q F2 6(#s)152 534 S(ort lexically)-6 E
(@articles = sort @files;)152 546 Q 6(#s)152 570 S
(ame thing, but with explicit sort routine)-6 E
(@articles = sort {$a cmp $b} @files;)152 582 Q 6(#n)152 606 S
(ow case\255insensitively)-6 E
(@articles = sort {uc\($a\) cmp uc\($b\)} @files;)152 618 Q 6(#s)152 642
S(ame thing in reversed order)-6 E(@articles = sort {$b cmp $a} @files;)
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(@articles = sort {$a <=> $b} @files;)152 690 Q 6(#s)152 714 S
(ort numerically descending)-6 E(@articles = sort {$b <=> $a} @files;)
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(qw\(dog cat x Cain Abel\);)6 E
(@george = qw\(gone chased yz Punished Axed\);)152 240 Q
(print sort @harry;)152 252 Q 6(#p)176 264 S(rints AbelCaincatdogx)-6 E
(print sort backwards @harry;)152 276 Q 6(#p)176 288 S
(rints xdogcatCainAbel)-6 E(print sort @george, \010to\010, @harry;)152
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E 6(#i)152 336 S(nefficiently sort by descending numeric compare using)
-6 E 6(#t)152 348 S(he first integer after the first = sign, or the)-6 E
6(#w)152 360 S(hole record case\255insensitively otherwise)-6 E
(my @new = sort {)152 384 Q
(\($b =~ /=\(\\d+\)/\)[0] <=> \($a =~ /=\(\\d+\)/\)[0])176 396 Q(||)200
408 Q 6(uc\($a\) cmp uc\($b\))176 420 R 6(}@)152 432 S(old;)-6 E 6(#s)
152 456 S(ame thing, but much more efficiently;)-6 E 6(#w)152 468 S
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E(my @nums = @caps = \(\);)152 492 Q(for \(@old\) {)152 504 Q
(push @nums, \( /=\(\\d+\)/ ? $1 : undef \);)176 516 Q
(push @caps, uc\($_\);)176 528 Q(})152 540 Q(my @new = @old[ sort {)152
564 Q($nums[$b] <=> $nums[$a])176 576 Q(||)200 588 Q
($caps[$a] cmp $caps[$b])176 600 Q 6(}0)176 612 S(..$#old)-6 E(];)152
624 Q 6(#s)152 648 S(ame thing, but without any temps)-6 E
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194 672 Q(||)218 684 Q($a\255>[2] cmp $b\255>[2])194 696 Q 6(}m)152 708
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120 Q 6(#$)12 G 6(aa)-6 G(nd $b are not set here)-6 E(package main;)152
144 Q(@new = sort other::backwards @old;)152 156 Q 6(#g)152 180 S
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(use sort \010stable\010;)152 192 Q
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Q 6(#f)152 228 S
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(use sort \010_mergesort\010;)152 240 Q 6(#n)12 G(ote discouraging _)-6
E(@new = sort { substr\($a, 3, 5\) cmp substr\($b, 3, 5\) } @old;)152
252 Q F0 -.8(Wa)128 270 S .142(rning: syntactical care is required when\
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(ant to sort)-.1 F(the list returned by the function call)128 282 Q F1
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(@contact = sort +find_records\(@key\);)152 312 Q
(@contact = sort &find_records\(@key\);)152 324 Q
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(If instead you w)128 354 R .295(ant to sort the array)-.1 F F1(@key)
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2.794 E F0 .294(then you)2.794 F(can use:)128 366 Q F1
(@contact = sort { find_records\(\) } @key;)152 384 Q
(@contact = sort find_records\(@key\);)152 396 Q
(@contact = sort\(find_records @key\);)152 408 Q
(@contact = sort\(find_records \(@key\)\);)152 420 Q F0 1.045(If you')
128 438 R 1.045(re using strict, you)-.5 F/F2 10/Times-Italic@0 SF 1.045
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546 Q F0 .537(is less than)3.037 F F1($x[2])3.037 E F0 .536
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128 576 Q F1(<=>)3.985 E F0(returns)3.985 E F1(undef)3.985 E F0 1.485
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-.74 E(splice)108 670.8 Q F3(ARRA)2.5 E(Y)-.945 E F0(or)2.5 E F3(EXPR)
2.5 E F0(,OFFSET)A(splice)108 682.8 Q F3(ARRA)2.5 E(Y)-.945 E F0(or)2.5
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F1(LENGTH)128 108 Q F0 2.269(are omitted, remo)4.769 F -.15(ve)-.15 G
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138 Q(wing equi)-.25 E -.25(va)-.25 G(lences hold \(assuming).25 E/F2 10
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($a[$i] = $y)152 204 Q(splice\(@a,$i,1,$y\))54 E F0
(Example, assuming array lengths are passed before arrays:)128 222 Q F2
(sub aeq {)152 240 Q 6(#c)12 G(ompare two list values)-6 E
(my\(@a\) = splice\(@_,0,shift\);)176 252 Q
(my\(@b\) = splice\(@_,0,shift\);)176 264 Q(return 0 unless @a == @b;)
176 276 Q 6(#s)12 G(ame len?)-6 E(while \(@a\) {)176 288 Q
(return 0 if pop\(@a\) ne pop\(@b\);)200 300 Q(})176 312 Q(return 1;)176
324 Q(})152 336 Q(if \(&aeq\($len,@foo[1..$len],0+@bar,@bar\)\) { ... })
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(array)128 378 Q 5.262(.T)-.65 G .262(he ar)-5.262 F .262
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430.8 Q -1.11(AT)-.92 G(TERN/)1.11 E(split)108 442.8 Q .798
(Splits the string)128 454.8 R F1(EXPR)3.298 E F0 .799
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E(If)128 556.8 Q F1(LIMIT)3.119 E F0 .619(is speci\214ed and positi)
3.119 F -.15(ve)-.25 G 3.119(,i).15 G 3.119(tr)-3.119 G .62
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ailing null \214elds are stripped \(which potential users of)2.77 F F2
(pop)128 592.8 Q F0 -.1(wo)2.557 G .057(uld do well to remember\).).1 F
(If)5.057 E F1(LIMIT)2.557 E F0 .057(is ne)2.557 F -.05(ga)-.15 G(ti).05
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(Note that splitting an)5.052 F F1(EXPR)2.553 E F0 .053(that e)2.553 F
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634.8 S .604(attern matching the empty string \(not to be confused with\
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646.8 R F1(EXPR)3.018 E F0 .518(into indi)3.018 F .518
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(print join\(\010:\010, split\(/ */, \010hi there\010\)\), "\\n";)152
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(print join\(\010:\010, split\(//, \010hi there\010\)\), "\\n";)152 102
Q F0(produces the output 'h:i: :t:h:e:r:e'.)128 120 Q 1.854
(Empty leading \214elds are produced when there are positi)128 138 R
-.15(ve)-.25 G 1.853(-width matches at the be).15 F 1.853
(ginning of the)-.15 F(string; a zero-width match at the be)128 150 Q
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(print join\(\010:\010, split\(/\(?=\\w\)/, \010hi there!\010\)\);)146
168 Q F0 .545(produces the output 'h:i :t:h:e:r:e!'. Empty trailing \
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(is a match at the end of the string \(and when)128 198 R/F2 9
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3.063(na).15 G .563(nd is not 0\), re)-3.063 F -.05(ga)-.15 G .563
(rdless of the length of).05 F(the match.)128 210 Q -.15(Fo)5 G 2.5(re)
.15 G(xample:)-2.65 E F1(print join\(\010:\010, split\(//,)146 228 Q
(\010hi there!\010, \2551\)\), "\\n";)18 E(print join\(\010:\010, split\
\(/\\W/, \010hi there!\010, \2551\)\), "\\n";)146 240 Q F0
(produce the output 'h:i: :t:h:e:r:e:!:' and 'hi:there:', respecti)128
258 Q -.15(ve)-.25 G(ly).15 E 2.5(,b)-.65 G
(oth with an empty trailing \214eld.)-2.5 E(The)128 276 Q F2(LIMIT)2.5 E
F0(parameter can be used to split a line partially)2.5 E F1
(\($login, $passwd, $remainder\) = split\(/:/, $_, 3\);)152 294 Q F0
.059(When assigning to a list, if)128 312 R F2(LIMIT)2.559 E F0 .059
(is omitted, or zero, Perl supplies a)2.559 F F2(LIMIT)2.559 E F0 .059
(one lar)2.559 F .06(ger than the number)-.18 F 1.117(of v)128 324 R
1.117(ariables in the list, to a)-.25 F -.2(vo)-.2 G 1.117
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1.416 -.15(ve b)-.2 H 1.116(een 4 by).15 F(def)128 336 Q 2.5(ault. In)
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3.177(If the)128 354 R F2 -.828(PA)5.677 G(TTERN)-.171 E F0 3.177(conta\
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g)5.677 F(substring in the delimiter)128 366 Q(.)-.55 E F1
(split\(/\([,\255]\)/, "1\25510,20", 3\);)152 384 Q F0
(produces the list v)128 402 Q(alue)-.25 E F1
(\(1, \010\255\010, 10, \010,\010, 20\))152 420 Q F0 .617
(If you had the entire header of a normal Unix email message in)128 438
R F1($header)3.116 E F0 3.116(,y)C .616(ou could split it up into)-3.116
F(\214elds and their v)128 450 Q(alues this w)-.25 E(ay:)-.1 E F1
($header =~ s/\\n\(?=\\s\)//g;)152 468 Q 6(#f)12 G
(ix continuation lines)-6 E 12(%hdrs =)152 480 R
(\(UNIX_FROM => split /^\(\\S*?\):\\s*/m, $header\);)12 E F0 .342
(The pattern)128 498 R F1(/PATTERN/)2.842 E F0 .343
(may be replaced with an e)2.842 F .343
(xpression to specify patterns that v)-.15 F .343(ary at runtime.)-.25 F
(\(T)128 510 Q 2.5(od)-.8 G 2.5(or)-2.5 G
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.012(As a special case, specifying a)128 528 R F2 -.828(PA)2.512 G
(TTERN)-.171 E F0 .012(of space \()2.512 F F1<08c22008>A F0 2.512(\)w)C
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F1(split\(\010\302 \010\))3.525 E F0 1.025(can be used to emulate)3.525
F/F3 10/Times-Bold@0 SF(awk)3.526 E F0 2.126 -.55('s d)D(ef).55 E 1.026
(ault beha)-.1 F(vior)-.2 E 3.526(,w)-.4 G(hereas)-3.526 E F1
(split\(/\302 /\))128 552 Q F0 .308(will gi)2.808 F .608 -.15(ve y)-.25
H .308(ou as man).15 F 2.808(yi)-.15 G .307
(nitial null \214elds \(empty string\) as there are leading spaces.)
-2.808 F(A)5.307 E F1(split)128 564 Q F0(on)3.281 E F1(/\\s+/)3.281 E F0
.781(is lik)3.281 F 3.281(ea)-.1 G F1(split\(\010\302 \010\))A F0 -.15
(ex)3.281 G .781(cept that an).15 F 3.281(yl)-.15 G .782
(eading whitespace produces a null \214rst)-3.281 F 2.5(\214eld. A)128
576 R F1(split)2.5 E F0(with no ar)2.5 E(guments really does a)-.18 E F1
(split\(\010\302 \010,\302 $_\))2.5 E F0(internally)2.5 E(.)-.65 E(A)128
594 Q F2 -.828(PA)2.5 G(TTERN)-.171 E F0(of)2.5 E F1(/^/)2.5 E F0
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(open\(PASSWD, \010/etc/passwd\010\);)152 630 Q(while \(<PASSWD>\) {)152
642 Q(chomp;)176 654 Q(\($login, $passwd, $uid, $gid,)176 666 Q
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702 Q F0 .506(As with re)128 720 R .506(gular pattern matching, an)-.15
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F1(sprintf)2.602 E F0 5.102(.S)C(ee)-5.102 E(belo)128 154.8 Q 3.194(wf)
-.25 G .694(or more details and see)-3.194 F F1(sprintf\(3\))3.193 E F0
(or)3.193 E F1(printf\(3\))3.193 E F0 .693(on your system for an e)3.193
F .693(xplanation of)-.15 F(the general principles.)128 166.8 Q -.15(Fo)
128 184.8 S 2.5(re).15 G(xample:)-2.65 E F1 6(#F)176 202.8 S
(ormat number with up to 8 leading zeroes)-6 E
($result = sprintf\("%08d", $number\);)176 214.8 Q 6(#R)176 238.8 S
(ound number to 3 digits after decimal point)-6 E
($rounded = sprintf\("%.3f", $number\);)176 250.8 Q F0 .136
(Perl does its o)128 268.8 R(wn)-.25 E F1(sprintf)2.636 E F0 .136
(formatting: it emulates the C function)2.636 F/F3 10/Times-Italic@0 SF
(sprintf)2.637 E F0 .137(\(3\), b)1.666 F .137(ut doesn')-.2 F 2.637(tu)
-.18 G .137(se it e)-2.637 F(xcept)-.15 E 3.529
(for \215oating-point numbers, and e)128 280.8 R -.15(ve)-.25 G 6.029
(nt).15 G 3.529(hen only standard modi\214ers are allo)-6.029 F 6.029
(wed. Non-standard)-.25 F -.15(ex)128 292.8 S(tensions in your local).15
E F3(sprintf)2.5 E F0(\(3\) are therefore una)1.666 E -.25(va)-.2 G
(ilable from Perl.).25 E(Unlik)128 310.8 Q(e)-.1 E F1(printf)3.267 E F0
(,)A F1(sprintf)3.267 E F0 .767
(does not do what you probably mean when you pass it an array as your)
3.267 F .712(\214rst ar)128 322.8 R .712(gument. The array is gi)-.18 F
-.15(ve)-.25 G 3.212(ns).15 G .712(calar conte)-3.212 F .711
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rmat, Perl will use the count of elements in the array as the format, w\
hich is almost ne)128 334.8 Q -.15(ve)-.25 G 2.5(ru).15 G(seful.)-2.5 E
(Perl')128 352.8 Q(s)-.55 E F1(sprintf)2.5 E F0(permits the follo)2.5 E
(wing uni)-.25 E -.15(ve)-.25 G(rsally-kno).15 E(wn con)-.25 E -.15(ve)
-.4 G(rsions:).15 E F1 18(%% a)146 370.8 R(percent sign)6 E 18(%c a)146
382.8 R(character with the given number)6 E 18(%s a)146 394.8 R(string)6
E 18(%d a)146 406.8 R(signed integer, in decimal)6 E 18(%u an)146 418.8
R(unsigned integer, in decimal)6 E 18(%o an)146 430.8 R
(unsigned integer, in octal)6 E 18(%x an)146 442.8 R
(unsigned integer, in hexadecimal)6 E 18(%e a)146 454.8 R
(floating\255point number, in scientific notation)6 E 18(%f a)146 466.8
R(floating\255point number, in fixed decimal notation)6 E 18(%g a)146
478.8 R(floating\255point number, in %e or %f notation)6 E F0
(In addition, Perl permits the follo)128 496.8 Q
(wing widely-supported con)-.25 E -.15(ve)-.4 G(rsions:).15 E F1 18
(%X like)146 514.8 R(%x, but using upper\255case letters)6 E 18(%E like)
146 526.8 R(%e, but using an upper\255case "E")6 E 18(%G like)146 538.8
R(%g, but with an upper\255case "E" \(if applicable\))6 E 18(%b an)146
550.8 R(unsigned integer, in binary)6 E 18(%B like)146 562.8 R
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574.8 R(pointer \(outputs the Perl value\010s address in hexadecimal\))6
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(*stores* the number of characters output so far)6 E
(into the next variable in the parameter list)176 598.8 Q F0(Finally)128
616.8 Q 2.542(,f)-.65 G .042(or backw)-2.542 F .042
(ard \(and we do mean `)-.1 F(`backw)-.74 E(ard')-.1 E .042
('\) compatibility)-.74 F 2.542(,P)-.65 G .043
(erl permits these unnecessary b)-2.542 F(ut)-.2 E(widely-supported con)
128 628.8 Q -.15(ve)-.4 G(rsions:).15 E F1 18(%i a)146 646.8 R
(synonym for %d)6 E 18(%D a)146 658.8 R(synonym for %ld)6 E 18(%U a)146
670.8 R(synonym for %lu)6 E 18(%O a)146 682.8 R(synonym for %lo)6 E 18
(%F a)146 694.8 R(synonym for %f)6 E F0 .418(Note that the number of e)
128 712.8 R .418
(xponent digits in the scienti\214c notation produced by)-.15 F F1(%e)
2.918 E F0(,)A F1(%E)2.918 E F0(,)A F1(%g)2.917 E F0(and)2.917 E F1(%G)
2.917 E F0(for)2.917 E .537(numbers with the modulus of the e)128 724.8
R .537
(xponent less than 100 is system-dependent: it may be three or less)-.15
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142.8 Q(x)-.15 E .985(An e)148 154.8 R .985
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166.8 Q(gument in the list, b)-.18 E(ut this allo)-.2 E(ws you to tak)
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(printf \010%2$d %1$d\010, 12, 34;)160 184.8 Q 6(#p)36 G(rints "34 12")
-6 E(printf \010%3$d %d %1$d\010, 1, 2, 3;)160 196.8 Q 6(#p)12 G
(rints "3 1 1")-6 E F0(\215ags)128 213.6 Q(one or more of:)148 225.6 Q
F1 12(space prefix)166 243.6 R(non\255negative number with a space)6 E
42(+p)166 255.6 S(refix non\255negative number with a plus sign)-42 E 42
<ad6c>166 267.6 S(eft\255justify within the field)-42 E 42(0u)166 279.6
S(se zeros, not spaces, to right\255justify)-42 E 42(#e)166 291.6 S
(nsure the leading "0" for any octal,)-42 E
(prefix non\255zero hexadecimal with "0x" or "0X",)214 303.6 Q
(prefix non\255zero binary with "0b" or "0B")214 315.6 Q F0 -.15(Fo)148
333.6 S 2.5(re).15 G(xample:)-2.65 E F1(printf \010<% d>\010,)160 351.6
Q 12(12; #)12 F(prints "< 12>")6 E(printf \010<%+d>\010,)160 363.6 Q 12
(12; #)12 F(prints "<+12>")6 E(printf \010<%6s>\010,)160 375.6 Q 12
(12; #)12 F(prints "<)6 E(12>")24 E(printf \010<%\2556s>\010, 12;)160
387.6 Q 6(#p)18 G(rints "<12)-6 E(>")24 E(printf \010<%06s>\010, 12;)160
399.6 Q 6(#p)18 G(rints "<000012>")-6 E(printf \010<%#o>\010,)160 411.6
Q 12(12; #)12 F(prints "<014>")6 E(printf \010<%#x>\010,)160 423.6 Q 12
(12; #)12 F(prints "<0xc>")6 E(printf \010<%#X>\010,)160 435.6 Q 12
(12; #)12 F(prints "<0XC>")6 E(printf \010<%#b>\010,)160 447.6 Q 12
(12; #)12 F(prints "<0b1100>")6 E(printf \010<%#B>\010,)160 459.6 Q 12
(12; #)12 F(prints "<0B1100>")6 E F0 .117
(When a space and a plus sign are gi)148 477.6 R -.15(ve)-.25 G 2.617
(na).15 G 2.617(st)-2.617 G .117
(he \215ags at once, a plus sign is used to pre\214x a positi)-2.617 F
-.15(ve)-.25 G(number)148 489.6 Q(.)-.55 E F1
(printf \010<%+ d>\010, 12;)160 507.6 Q 6(#p)18 G(rints "<+12>")-6 E
(printf \010<% +d>\010, 12;)160 519.6 Q 6(#p)18 G(rints "<+12>")-6 E F0
.01(When the # \215ag and a precision are gi)148 537.6 R -.15(ve)-.25 G
2.51(ni).15 G 2.51(nt)-2.51 G(he)-2.51 E F1(%o)2.51 E F0(con)2.51 E -.15
(ve)-.4 G .01(rsion, the precision is incremented if it').15 F(s)-.55 E
(necessary for the leading `)148 549.6 Q(`0')-.74 E('.)-.74 E F1
(printf \010<%#.5o>\010, 012;)160 567.6 Q 6(#p)36 G(rints "<00012>")-6 E
(printf \010<%#.5o>\010, 012345;)160 579.6 Q 6(#p)18 G(rints "<012345>")
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F0 -.15(ve)128 608.4 S(ctor \215ag).15 E .116
(This \215ag tells Perl to interpret the supplied string as a v)148
620.4 R .117(ector of inte)-.15 F .117(gers, one for each character in)
-.15 F .929(the string. Perl applies the format to each inte)148 632.4 R
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(separator \(a dot)148 644.4 R F1(.)3.51 E F0 1.01(by def)3.51 F 1.01
(ault\). This can be useful for displaying ordinal v)-.1 F 1.01
(alues of characters in)-.25 F(arbitrary strings:)148 656.4 Q F1
(printf "%vd", "AB\\x{100}";)160 674.4 Q 6(#p)66 G(rints "65.66.256")-6
E(printf "version is v%vd\\n", $^V;)160 686.4 Q 6(#P)30 G
(erl\010s version)-6 E F0(Put an asterisk)148 704.4 Q F1(*)2.5 E F0
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(printf "address is %*vX\\n", ":", $addr;)160 84 Q 6(#I)18 G
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126 Q(e)-.1 E F1(*2$v)2.5 E F0 2.5(;f)C(or e)-2.5 E(xample:)-.15 E F1
(printf \010%*4$vX %*4$vX %*4$vX\010, @addr[1..3], ":";)160 144 Q 6(#3I)
18 G(Pv6 addresses)-6 E F0(\(minimum\) width)128 160.8 Q(Ar)148 172.8 Q
.787(guments are usually formatted to be only as wide as required to di\
splay the gi)-.18 F -.15(ve)-.25 G 3.288(nv).15 G .788(alue. Y)-3.538 F
(ou)-1.1 E .682(can o)148 184.8 R -.15(ve)-.15 G .681
(rride the width by putting a number here, or get the width from the ne)
.15 F .681(xt ar)-.15 F .681(gument \(with)-.18 F F1(*)148 196.8 Q F0
2.5(\)o)C 2.5(rf)-2.5 G(rom a speci\214ed ar)-2.5 E(gument \(e.g., with)
-.18 E F1(*2$)2.5 E F0(\):)A F1(printf "<%s>", "a";)160 214.8 Q 6(#p)42
G(rints "<a>")-6 E(printf "<%6s>", "a";)160 226.8 Q 6(#p)36 G(rints "<)
-6 E(a>")30 E(printf "<%*s>", 6, "a";)160 238.8 Q 6(#p)18 G(rints "<)-6
E(a>")30 E(printf "<%*2$s>", "a", 6; # prints "<)160 250.8 Q(a>")30 E
(printf "<%2s>", "long";)160 262.8 Q 6(#p)18 G
(rints "<long>" \(does not truncate\))-6 E F0 2.565
(If a \214eld width obtained through)148 280.8 R F1(*)5.065 E F0 2.565
(is ne)5.065 F -.05(ga)-.15 G(ti).05 E -.15(ve)-.25 G 5.066(,i).15 G
5.066(th)-5.066 G 2.566(as the same ef)-5.066 F 2.566(fect as the)-.25 F
F1<ad>5.066 E F0 2.566(\215ag: left-)5.066 F(justi\214cation.)148 292.8
Q(precision, or maximum width)128 309.6 Q -1.1(Yo)148 321.6 S 6.141(uc)
1.1 G 3.641(an specify a precision \(for numeric con)-6.141 F -.15(ve)
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Q -.15(ve)-.4 G .232(rsions\) by specifying a).15 F F1(.)2.732 E F0
(follo)2.732 E .232(wed by a number)-.25 F 5.232(.F)-.55 G .232
(or \215oating-point formats e)-5.382 F(xcept)-.15 E F1(g)2.732 E F0
(and)2.732 E F1(G)2.732 E F0(,)A 1.642(this speci\214es ho)148 345.6 R
4.142(wm)-.25 G(an)-4.142 E 4.142(yp)-.15 G 1.642
(laces right of the decimal point to sho)-4.142 F 4.142(w\()-.25 G 1.642
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-.15(ex)148 357.6 S(ample:).15 E F1 6(#t)160 375.6 S
(hese examples are subject to system\255specific variation)-6 E
(printf \010<%f>\010, 1;)160 387.6 Q 6(#p)24 G(rints "<1.000000>")-6 E
(printf \010<%.1f>\010, 1;)160 399.6 Q 6(#p)12 G(rints "<1.0>")-6 E
(printf \010<%.0f>\010, 1;)160 411.6 Q 6(#p)12 G(rints "<1>")-6 E
(printf \010<%e>\010, 10;)160 423.6 Q 6(#p)18 G(rints "<1.000000e+01>")
-6 E(printf \010<%.1e>\010, 10; # prints "<1.0e+01>")160 435.6 Q F0 -.15
(Fo)148 453.6 S 3.12(r`).15 G(`g')-3.86 E 3.12('a)-.74 G .62(nd `)-3.12
F(`G')-.74 E .621
(', this speci\214es the maximum number of digits to sho)-.74 F 1.921
-.65(w, i)-.25 H .621(ncluding thoe prior to).65 F
(the decimal point and those after it; for e)148 465.6 Q(xample:)-.15 E
F1 6(#T)160 483.6 S
(hese examples are subject to system\255specific variation.)-6 E
(printf \010<%g>\010, 1;)160 495.6 Q 6(#p)48 G(rints "<1>")-6 E
(printf \010<%.10g>\010, 1;)160 507.6 Q 6(#p)30 G(rints "<1>")-6 E
(printf \010<%g>\010, 100;)160 519.6 Q 6(#p)36 G(rints "<100>")-6 E
(printf \010<%.1g>\010, 100;)160 531.6 Q 6(#p)24 G(rints "<1e+02>")-6 E
(printf \010<%.2g>\010, 100.01; # prints "<1e+02>")160 543.6 Q
(printf \010<%.5g>\010, 100.01; # prints "<100.01>")160 555.6 Q
(printf \010<%.4g>\010, 100.01; # prints "<100>")160 567.6 Q F0 -.15(Fo)
148 585.6 S 2.726(ri).15 G(nte)-2.726 E .226(ger con)-.15 F -.15(ve)-.4
G .226(rsions, specifying a precision implies that the output of the nu\
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(be zero-padded to this width, where the 0 \215ag is ignored:)148 597.6
Q F1(printf \010<%.6d>\010, 1;)160 615.6 Q 6(#p)36 G(rints "<000001>")-6
E(printf \010<%+.6d>\010, 1;)160 627.6 Q 6(#p)30 G(rints "<+000001>")-6
E(printf \010<%\25510.6d>\010, 1;)160 639.6 Q 6(#p)18 G(rints "<000001)
-6 E(>")24 E(printf \010<%10.6d>\010, 1;)160 651.6 Q 6(#p)24 G(rints "<)
-6 E(000001>")24 E(printf \010<%010.6d>\010, 1;)160 663.6 Q 6(#p)18 G
(rints "<)-6 E(000001>")24 E(printf \010<%+10.6d>\010, 1;)160 675.6 Q 6
(#p)18 G(rints "<)-6 E(+000001>")18 E(printf \010<%.6x>\010, 1;)160
699.6 Q 6(#p)36 G(rints "<000001>")-6 E(printf \010<%#.6x>\010, 1;)160
711.6 Q 6(#p)30 G(rints "<0x000001>")-6 E
(printf \010<%\25510.6x>\010, 1;)160 723.6 Q 6(#p)18 G(rints "<000001)-6
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(printf \010<%.5s>\010, "truncated";)160 144 Q 6(#p)18 G
(rints "<trunc>")-6 E(printf \010<%10.5s>\010, "truncated"; # prints "<)
160 156 Q(trunc>")30 E F0 -1.1(Yo)148 174 S 2.5(uc)1.1 G
(an also get the precision from the ne)-2.5 E(xt ar)-.15 E(gument using)
-.18 E F1(.*)2.5 E F0(:)A F1(printf \010<%.6x>\010, 1;)160 192 Q 6(#p)42
G(rints "<000001>")-6 E(printf \010<%.*x>\010, 6, 1;)160 204 Q 6(#p)24 G
(rints "<000001>")-6 E F0(If a precision obtained through)148 222 Q F1
(*)2.5 E F0(is ne)2.5 E -.05(ga)-.15 G(ti).05 E -.15(ve)-.25 G 2.5(,i)
.15 G 2.5(tc)-2.5 G(ounts as ha)-2.5 E(ving no precision at all.)-.2 E
F1(printf \010<%.*s>\010,)160 240 Q(7, "string";)12 E 6(#p)18 G
(rints "<string>")-6 E(printf \010<%.*s>\010,)160 252 Q(3, "string";)12
E 6(#p)18 G(rints "<str>")-6 E(printf \010<%.*s>\010,)160 264 Q
(0, "string";)12 E 6(#p)18 G(rints "<>")-6 E
(printf \010<%.*s>\010, \2551, "string";)160 276 Q 6(#p)18 G
(rints "<string>")-6 E(printf \010<%.*d>\010,)160 300 Q(1, 0;)12 E 6(#p)
18 G(rints "<0>")-6 E(printf \010<%.*d>\010,)160 312 Q(0, 0;)12 E 6(#p)
18 G(rints "<>")-6 E(printf \010<%.*d>\010, \2551, 0;)160 324 Q 6(#p)18
G(rints "<0>")-6 E F0 -1.1(Yo)148 342 S 2.72(uc)1.1 G .22
(annot currently get the precision from a speci\214ed number)-2.72 F
2.72(,b)-.4 G .22(ut it is intended that this will be)-2.92 F
(possible in the future, for e)148 354 Q(xample using)-.15 E F1(.*2$)2.5
E F0(:)A F1(printf "<%.*2$x>", 1, 6;)160 372 Q 6(#I)18 G
(NVALID, but in future will print "<000001>")-6 E F0(size)128 388.8 Q
-.15(Fo)148 400.8 S 2.962(rn).15 G .462(umeric con)-2.962 F -.15(ve)-.4
G .462
(rsions, you can specify the size to interpret the number as using).15 F
F1(l)2.961 E F0(,)A F1(h)2.961 E F0(,)A F1(V)2.961 E F0(,)A F1(q)2.961 E
F0(,)A F1(L)2.961 E F0(,)A(or)148 412.8 Q F1(ll)2.636 E F0 2.636(.F)C
.136(or inte)-2.786 F .136(ger con)-.15 F -.15(ve)-.4 G .136(rsions \()
.15 F F1 -12.135 6.136(duoxXb i D U O)D F0 .137
(\), numbers are usually assumed to be)-6.136 F(whate)148 424.8 Q -.15
(ve)-.25 G 2.82(rt).15 G .32(he def)-2.82 F .32(ault inte)-.1 F .32
(ger size is on your platform \(usually 32 or 64 bits\), b)-.15 F .32
(ut you can o)-.2 F -.15(ve)-.15 G(rride).15 E(this to use instead one \
of the standard C types, as supported by the compiler used to b)148
436.8 Q(uild Perl:)-.2 E F1 54(hh interpret)166 454.8 R
(integer as C type "char" or "unsigned char")6 E(on Perl 5.14 or later)
238 466.8 Q 66(hi)166 478.8 S
(nterpret integer as C type "short" or "unsigned short")-66 E 66(ji)166
490.8 S(ntepret integer as C type "intmax_t" on Perl 5.14)-66 E
(or later, and only with a C99 compiler \(unportable\))238 502.8 Q 66
(li)166 514.8 S(nterpret integer as C type "long" or "unsigned long")-66
E(q, L, or ll interpret integer as C type "long long", "unsigned long l\
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(which can be bit\255anded with \(for example\) S_IFREG)200 528 Q
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(S_ISREG\($mode\) S_ISDIR\($mode\) S_ISLNK\($mode\))152 588 Q
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2.69(,o)C(r)-2.69 E F1(eof)2.69 E F0 .189
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(than relying on 0, 1, and 2.)128 168 Q -.15(Fo)5 G 2.5(re).15 G
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(sub systell { sysseek\($_[0], 0, SEEK_CUR\) })152 198 Q F0 .102
(Returns the ne)128 216 R 2.601(wp)-.25 G .101
(osition, or the unde\214ned v)-2.601 F .101(alue on f)-.25 F 2.601
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F .387(ailure, yet you can still easily)-.1 F(determine the ne)128 240 Q
2.5(wp)-.25 G(osition.)-2.5 E(system)108 256.8 Q F3(LIST)2.5 E F0
(system)108 268.8 Q F3(PR)2.5 E .25(OGRAM LIST)-.36 F F0 .928(Does e)128
280.8 R .928(xactly the same thing as)-.15 F F1 .928(exec LIST)3.428 F
F0 3.428(,e)C .928
(xcept that a fork is done \214rst and the parent process)-3.578 F -.1
(wa)128 292.8 S .518(its for the child process to e).1 F 3.019
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352.8 Q F0 1.752(on Unix platforms, b)4.252 F 1.752(ut v)-.2 F 1.752
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(If there are no shell metacharacters in the)6.752 F(ar)128 364.8 Q
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(ut this may not be supported on some platforms \(see perlport\).)-.2 F
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(If you')128 502.8 R 3.314(dl)-.5 G(ik)-3.314 E 3.314(et)-.1 G 3.314(om)
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(Returns the number of bytes actually written,)5.613 F(or)128 370.8 Q F1
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184.8 Q(uc)108 201.6 Q F2(EXPR)2.5 E F0(uc)108 213.6 Q .572
(Returns an uppercased v)128 213.6 R .572(ersion of)-.15 F F2(EXPR)3.072
E F0 5.572(.T)C .572(his is the internal function implementing the)
-5.572 F F1(\\U)3.073 E F0 .573(escape in)3.073 F .438
(double-quoted strings.)128 225.6 R .438
(It does not attempt to do titlecase mapping on initial letters.)5.438 F
.438(See `)5.438 F(`uc\214rst')-.74 E 2.938('f)-.74 G(or)-2.938 E(that.)
128 237.6 Q(If)128 255.6 Q F2(EXPR)2.5 E F0(is omitted, uses)2.5 E F1
($_)2.5 E F0(.)A(This function beha)128 273.6 Q -.15(ve)-.2 G 2.5(st).15
G(he same w)-2.5 E(ay under v)-.1 E
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G(oes.)-2.5 E(uc\214rst)108 290.4 Q F2(EXPR)2.5 E F0(uc\214rst)108 302.4
Q 1.45(Returns the v)128 314.4 R 1.45(alue of)-.25 F F2(EXPR)3.95 E F0
1.45(with the \214rst character in uppercase \(titlecase in Unicode\).)
3.95 F 1.451(This is the)6.451 F(internal function implementing the)128
326.4 Q F1(\\u)2.5 E F0(escape in double-quoted strings.)2.5 E(If)128
344.4 Q F2(EXPR)2.5 E F0(is omitted, uses)2.5 E F1($_)2.5 E F0(.)A
(This function beha)128 362.4 Q -.15(ve)-.2 G 2.5(st).15 G(he same w)
-2.5 E(ay under v)-.1 E(arious pragma, such as in a locale, as `)-.25 E
(`lc')-.74 E 2.5('d)-.74 G(oes.)-2.5 E(umask)108 379.2 Q F2(EXPR)2.5 E
F0(umask)108 391.2 Q 1.039(Sets the umask for the process to)128 403.2 R
F2(EXPR)3.538 E F0 1.038(and returns the pre)3.538 F 1.038(vious v)-.25
F 3.538(alue. If)-.25 F F2(EXPR)3.538 E F0 1.038(is omitted, merely)
3.538 F(returns the current umask.)128 415.2 Q .027(The Unix permission)
128 433.2 R F1<72777872ad78adadad>2.527 E F0 .028
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2.527 F F1(0750)2.528 E F0 2.352
(\(the leading 0 indicates octal and isn')128 445.2 R 4.852(to)-.18 G
2.352(ne of the digits\).)-4.852 F(The)7.352 E F1(umask)4.852 E F0 -.25
(va)4.852 G 2.351(lue is such a number).25 F 2.305
(representing disabled permissions bits.)128 457.2 R 2.306
(The permission \(or `)7.306 F(`mode')-.74 E 2.306('\) v)-.74 F 2.306
(alues you pass)-.25 F F1(mkdir)4.806 E F0(or)4.806 E F1(sysopen)128
469.2 Q F0 .3(are modi\214ed by your umask, so e)2.8 F -.15(ve)-.25 G
2.8(ni).15 G 2.8(fy)-2.8 G .3(ou tell)-2.8 F F1(sysopen)2.8 E F0 .3
(to create a \214le with permissions)2.8 F F1(0777)128 481.2 Q F0 3.204
(,i)C 3.204(fy)-3.204 G .704(our umask is)-3.204 F F1(0022)3.204 E F0
3.205(,t)C .705
(hen the \214le will actually be created with permissions)-3.205 F F1
(0755)3.205 E F0 5.705(.I)C 3.205(fy)-5.705 G(our)-3.205 E F1(umask)128
493.2 Q F0(were)3.439 E F1(0027)3.439 E F0 .939(\(group can')3.439 F
3.439(tw)-.18 G .939(rite; others can')-3.439 F 3.439(tr)-.18 G .938
(ead, write, or e)-3.439 F -.15(xe)-.15 G .938(cute\), then passing).15
F F1(sysopen)3.438 E(0666)128 505.2 Q F0 -.1(wo)2.5 G
(uld create a \214le with mode).1 E F1(0640)2.5 E F0(\(because)2.5 E F1
(0666 &~ 027)2.5 E F0(is)2.5 E F1(0640)2.5 E F0(\).)A(Here')128 523.2 Q
2.581(ss)-.55 G .081(ome advice: supply a creation mode of)-2.581 F F1
(0666)2.582 E F0 .082(for re)2.582 F .082(gular \214les \(in)-.15 F F1
(sysopen)2.582 E F0 2.582(\)a)C .082(nd one of)-2.582 F F1(0777)2.582 E
F0 .676(for directories \(in)128 535.2 R F1(mkdir)3.176 E F0 3.176(\)a)C
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(This gi)5.676 F -.15(ve)-.25 G 3.176(su).15 G .675
(sers the freedom of choice: if the)-3.176 F 3.175(yw)-.15 G(ant)-3.275
E 1.404(protected \214les, the)128 547.2 R 3.904(ym)-.15 G 1.404
(ight choose process umasks of)-3.904 F F1(022)3.904 E F0(,)A F1(027)
3.904 E F0 3.904(,o)C 3.905(re)-3.904 G -.15(ve)-4.155 G 3.905(nt).15 G
1.405(he particularly antisocial)-3.905 F 1.996(mask of)128 559.2 R F1
(077)4.496 E F0 6.996(.P)C 1.996(rograms should rarely if e)-6.996 F
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(.T)-.55 G(he)-6.995 E -.15(ex)128 571.2 S 1.265
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(ept pri)-.1 F -.25(va)-.25 G 1.266(te: mail \214les, web bro).25 F
1.266(wser cookies,)-.25 F/F3 10/Times-Italic@0 SF(.rhosts)128 583.2 Q
F0(\214les, and so on.)2.5 E(If)128 601.2 Q F3(umask)2.955 E F0 .454(\(\
2\) is not implemented on your system and you are trying to restrict ac\
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(\(EXPR & 0700\) > 0)128 613.2 R F0 .012(\), raises an e)B 2.512
(xception. If)-.15 F F3(umask)2.512 E F0 .012
(\(2\) is not implemented and you are not trying)1.666 F
(to restrict access for yourself, returns)128 625.2 Q F1(undef)2.5 E F0
(.)A .516(Remember that a umask is a number)128 643.2 R 3.016(,u)-.4 G
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198 Q(select undef, undef, undef, 0.25;)152 210 Q
(\($a, $b, undef, $c\) = &foo;)152 222 Q 6(#I)42 G
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128 240 Q 2.5(,n)-.4 G(ot a list operator)-2.5 E(.)-.55 E(unlink)108
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(unlink @goners;)152 322.8 Q(unlink glob "*.bak";)152 334.8 Q F0 .547
(On error)128 352.8 R(,)-.4 E F2(unlink)3.047 E F0 .548
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364.8 Q -.15(ve)-.15 G 2.5(,t).15 G(ry them one at a time:)-2.5 E F2
(foreach my $file \( @goners \) {)158 382.8 Q
(unlink $file or warn "Could not unlink $file: $!";)182 394.8 Q(})158
406.8 Q F0(Note:)128 424.8 Q F2(unlink)4.362 E F0 1.862(will not attemp\
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(perating)-2.729 E 2.5(systems. Use)128 460.8 R F2(rmdir)2.5 E F0
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2.87(alues. \(In)-.25 F(scalar)2.87 E(conte)128 531.6 Q
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128 549.6 Q F1(EXPR)2.5 E F0(is omitted, unpacks the)2.5 E F2($_)2.5 E
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(The string is brok)128 567.6 R .073(en into chunks described by the)-.1
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(Breaks the binding between a v)128 346.8 R .455(ariable and a package.)
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387.6 Q F2(EXPR)2.5 E F0(,LIST)A 2.219(Does the opposite of a)128 399.6
R F1(shift)4.719 E F0 7.219(.O)C 4.719(rt)-7.219 G 2.219
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2.5(wn)-.25 G(umber of elements in the array)-2.5 E(.)-.65 E F1
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(to do the re)2.5 E -.15(ve)-.25 G(rse.).15 E 2.513
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108 530.4 Q F2(VERSION)2.5 E F0(use Module)108 542.4 Q F2(LIST)2.5 E F0
(use Module)108 554.4 Q(use)108 566.4 Q F2(VERSION)2.5 E F0 .009(Import\
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(BEGIN { require Module; Module\255>import\( LIST \); })152 608.4 Q F0
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(In the peculiar)128 644.4 R F1 1.516(use VERSION)4.017 F F0(form,)4.016
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-.15 F(precedence as in)128 466.8 Q F2
(vec\($image, $max_x * $x + $y, 8\) = 3;)152 484.8 Q F0 .81
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(vec\($foo, 3,)152 96 R(16\) = 0x726C; # \010PerlPerl\010)6 E 6
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(r\010 is "\\x72")-6 E(vec\($foo, 45,)152 168 Q(2\) = 3;)12 E 6<2308>36
G 6(PerlPerlPer\010 .)-6 F("\\x0c")6 E(vec\($foo, 93,)152 180 Q
(1\) = 1;)12 E 6<2308>36 G 6(PerlPerlPer\010 .)-6 F("\\x2c")6 E
(vec\($foo, 94,)152 192 Q(1\) = 1;)12 E 6<2308>36 G(PerlPerlPerl\010)-6
E 6<2308>338 204 S(l\010 is "\\x6c")-6 E F0 1.6 -.8(To t)128 222 T
(ransform a bit v).8 E(ector into a string or list of 0')-.15 E 2.5(sa)
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($bits = unpack\("b*", $vector\);)152 240 Q
(@bits = split\(//, unpack\("b*", $vector\)\);)152 252 Q F0(If you kno)
128 270 Q 2.5(wt)-.25 G(he e)-2.5 E
(xact length in bits, it can be used in place of the)-.15 E F1(*)2.5 E
F0(.)A(Here is an e)128 288 Q(xample to illustrate ho)-.15 E 2.5(wt)-.25
G(he bits actually f)-2.5 E(all in place:)-.1 E F1
(#!/usr/bin/perl \255wl)152 306 Q(print <<\010EOT\010;)152 330 Q 54
(0123)356 342 S(unpack\("V",$_\) 01234567890123456789012345678901)266
354 Q<adadadadadadadadadadadadadadadadadadadadadadadadadadadadadadadadad
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366 Q(EOT)152 378 Q(for $w \(0..3\) {)152 402 Q($width = 2**$w;)176 414
Q(for \($shift=0; $shift < $width; ++$shift\) {)176 426 Q
(for \($off=0; $off < 32/$width; ++$off\) {)200 438 Q
($str = pack\("B*", "0"x32\);)224 450 Q($bits = \(1<<$shift\);)224 462 Q
(vec\($str, $off, $width\) = $bits;)224 474 Q
($res = unpack\("b*",$str\);)224 486 Q($val = unpack\("V", $str\);)224
498 Q(write;)224 510 Q(})200 522 Q(})176 534 Q(})152 546 Q
(format STDOUT =)152 570 Q
(vec\($_,@#,@#\) = @<< == @######### @>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>)
152 582 Q($off, $width, $bits, $val, $res)152 594 Q(.)152 606 Q 1.666
(__)152 618 S -4.334(END_ _)-1.666 F F0(Re)128 636 Q -.05(ga)-.15 G .235
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108 Q(vec\($_, 0, 1\) = 1)152 120 Q 54(== 1)18 F
(10000000000000000000000000000000)6 E(vec\($_, 1, 1\) = 1)152 132 Q 54
(== 2)18 F(01000000000000000000000000000000)6 E(vec\($_, 2, 1\) = 1)152
144 Q 54(== 4)18 F(00100000000000000000000000000000)6 E
(vec\($_, 3, 1\) = 1)152 156 Q 54(== 8)18 F
(00010000000000000000000000000000)6 E(vec\($_, 4, 1\) = 1)152 168 Q 48
(== 16)18 F(00001000000000000000000000000000)6 E(vec\($_, 5, 1\) = 1)152
180 Q 48(== 32)18 F(00000100000000000000000000000000)6 E
(vec\($_, 6, 1\) = 1)152 192 Q 48(== 64)18 F
(00000010000000000000000000000000)6 E(vec\($_, 7, 1\) = 1)152 204 Q 42
(== 128)18 F(00000001000000000000000000000000)6 E(vec\($_, 8, 1\) = 1)
152 216 Q 42(== 256)18 F(00000000100000000000000000000000)6 E
(vec\($_, 9, 1\) = 1)152 228 Q 42(== 512)18 F
(00000000010000000000000000000000)6 E(vec\($_,10, 1\) = 1)152 240 Q 36
(== 1024)18 F(00000000001000000000000000000000)6 E(vec\($_,11, 1\) = 1)
152 252 Q 36(== 2048)18 F(00000000000100000000000000000000)6 E
(vec\($_,12, 1\) = 1)152 264 Q 36(== 4096)18 F
(00000000000010000000000000000000)6 E(vec\($_,13, 1\) = 1)152 276 Q 36
(== 8192)18 F(00000000000001000000000000000000)6 E(vec\($_,14, 1\) = 1)
152 288 Q 30(== 16384)18 F(00000000000000100000000000000000)6 E
(vec\($_,15, 1\) = 1)152 300 Q 30(== 32768)18 F
(00000000000000010000000000000000)6 E(vec\($_,16, 1\) = 1)152 312 Q 30
(== 65536)18 F(00000000000000001000000000000000)6 E(vec\($_,17, 1\) = 1)
152 324 Q 24(== 131072)18 F(00000000000000000100000000000000)6 E
(vec\($_,18, 1\) = 1)152 336 Q 24(== 262144)18 F
(00000000000000000010000000000000)6 E(vec\($_,19, 1\) = 1)152 348 Q 24
(== 524288)18 F(00000000000000000001000000000000)6 E
(vec\($_,20, 1\) = 1)152 360 Q 18(== 1048576)18 F
(00000000000000000000100000000000)6 E(vec\($_,21, 1\) = 1)152 372 Q 18
(== 2097152)18 F(00000000000000000000010000000000)6 E
(vec\($_,22, 1\) = 1)152 384 Q 18(== 4194304)18 F
(00000000000000000000001000000000)6 E(vec\($_,23, 1\) = 1)152 396 Q 18
(== 8388608)18 F(00000000000000000000000100000000)6 E
(vec\($_,24, 1\) = 1)152 408 Q 12(== 16777216)18 F
(00000000000000000000000010000000)6 E(vec\($_,25, 1\) = 1)152 420 Q 12
(== 33554432)18 F(00000000000000000000000001000000)6 E
(vec\($_,26, 1\) = 1)152 432 Q 12(== 67108864)18 F
(00000000000000000000000000100000)6 E(vec\($_,27, 1\) = 1)152 444 Q 6
(== 134217728)18 F(00000000000000000000000000010000)6 E
(vec\($_,28, 1\) = 1)152 456 Q 6(== 268435456)18 F
(00000000000000000000000000001000)6 E(vec\($_,29, 1\) = 1)152 468 Q 6
(== 536870912)18 F(00000000000000000000000000000100)6 E
(vec\($_,30, 1\) = 1)152 480 Q
(== 1073741824 00000000000000000000000000000010)18 E
(vec\($_,31, 1\) = 1)152 492 Q
(== 2147483648 00000000000000000000000000000001)18 E
(vec\($_, 0, 2\) = 1)152 504 Q 54(== 1)18 F
(10000000000000000000000000000000)6 E(vec\($_, 1, 2\) = 1)152 516 Q 54
(== 4)18 F(00100000000000000000000000000000)6 E(vec\($_, 2, 2\) = 1)152
528 Q 48(== 16)18 F(00001000000000000000000000000000)6 E
(vec\($_, 3, 2\) = 1)152 540 Q 48(== 64)18 F
(00000010000000000000000000000000)6 E(vec\($_, 4, 2\) = 1)152 552 Q 42
(== 256)18 F(00000000100000000000000000000000)6 E(vec\($_, 5, 2\) = 1)
152 564 Q 36(== 1024)18 F(00000000001000000000000000000000)6 E
(vec\($_, 6, 2\) = 1)152 576 Q 36(== 4096)18 F
(00000000000010000000000000000000)6 E(vec\($_, 7, 2\) = 1)152 588 Q 30
(== 16384)18 F(00000000000000100000000000000000)6 E(vec\($_, 8, 2\) = 1)
152 600 Q 30(== 65536)18 F(00000000000000001000000000000000)6 E
(vec\($_, 9, 2\) = 1)152 612 Q 24(== 262144)18 F
(00000000000000000010000000000000)6 E(vec\($_,10, 2\) = 1)152 624 Q 18
(== 1048576)18 F(00000000000000000000100000000000)6 E
(vec\($_,11, 2\) = 1)152 636 Q 18(== 4194304)18 F
(00000000000000000000001000000000)6 E(vec\($_,12, 2\) = 1)152 648 Q 12
(== 16777216)18 F(00000000000000000000000010000000)6 E
(vec\($_,13, 2\) = 1)152 660 Q 12(== 67108864)18 F
(00000000000000000000000000100000)6 E(vec\($_,14, 2\) = 1)152 672 Q 6
(== 268435456)18 F(00000000000000000000000000001000)6 E
(vec\($_,15, 2\) = 1)152 684 Q
(== 1073741824 00000000000000000000000000000010)18 E
(vec\($_, 0, 2\) = 2)152 696 Q 54(== 2)18 F
(01000000000000000000000000000000)6 E(vec\($_, 1, 2\) = 2)152 708 Q 54
(== 8)18 F(00010000000000000000000000000000)6 E(vec\($_, 2, 2\) = 2)152
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152 108 Q 36(== 2048)18 F(00000000000100000000000000000000)6 E
(vec\($_, 6, 2\) = 2)152 120 Q 36(== 8192)18 F
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152 144 Q 24(== 131072)18 F(00000000000000000100000000000000)6 E
(vec\($_, 9, 2\) = 2)152 156 Q 24(== 524288)18 F
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(== 2097152)18 F(00000000000000000000010000000000)6 E
(vec\($_,11, 2\) = 2)152 180 Q 18(== 8388608)18 F
(00000000000000000000000100000000)6 E(vec\($_,12, 2\) = 2)152 192 Q 12
(== 33554432)18 F(00000000000000000000000001000000)6 E
(vec\($_,13, 2\) = 2)152 204 Q 6(== 134217728)18 F
(00000000000000000000000000010000)6 E(vec\($_,14, 2\) = 2)152 216 Q 6
(== 536870912)18 F(00000000000000000000000000000100)6 E
(vec\($_,15, 2\) = 2)152 228 Q
(== 2147483648 00000000000000000000000000000001)18 E
(vec\($_, 0, 4\) = 1)152 240 Q 54(== 1)18 F
(10000000000000000000000000000000)6 E(vec\($_, 1, 4\) = 1)152 252 Q 48
(== 16)18 F(00001000000000000000000000000000)6 E(vec\($_, 2, 4\) = 1)152
264 Q 42(== 256)18 F(00000000100000000000000000000000)6 E
(vec\($_, 3, 4\) = 1)152 276 Q 36(== 4096)18 F
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(== 65536)18 F(00000000000000001000000000000000)6 E(vec\($_, 5, 4\) = 1)
152 300 Q 18(== 1048576)18 F(00000000000000000000100000000000)6 E
(vec\($_, 6, 4\) = 1)152 312 Q 12(== 16777216)18 F
(00000000000000000000000010000000)6 E(vec\($_, 7, 4\) = 1)152 324 Q 6
(== 268435456)18 F(00000000000000000000000000001000)6 E
(vec\($_, 0, 4\) = 2)152 336 Q 54(== 2)18 F
(01000000000000000000000000000000)6 E(vec\($_, 1, 4\) = 2)152 348 Q 48
(== 32)18 F(00000100000000000000000000000000)6 E(vec\($_, 2, 4\) = 2)152
360 Q 42(== 512)18 F(00000000010000000000000000000000)6 E
(vec\($_, 3, 4\) = 2)152 372 Q 36(== 8192)18 F
(00000000000001000000000000000000)6 E(vec\($_, 4, 4\) = 2)152 384 Q 24
(== 131072)18 F(00000000000000000100000000000000)6 E
(vec\($_, 5, 4\) = 2)152 396 Q 18(== 2097152)18 F
(00000000000000000000010000000000)6 E(vec\($_, 6, 4\) = 2)152 408 Q 12
(== 33554432)18 F(00000000000000000000000001000000)6 E
(vec\($_, 7, 4\) = 2)152 420 Q 6(== 536870912)18 F
(00000000000000000000000000000100)6 E(vec\($_, 0, 4\) = 4)152 432 Q 54
(== 4)18 F(00100000000000000000000000000000)6 E(vec\($_, 1, 4\) = 4)152
444 Q 48(== 64)18 F(00000010000000000000000000000000)6 E
(vec\($_, 2, 4\) = 4)152 456 Q 36(== 1024)18 F
(00000000001000000000000000000000)6 E(vec\($_, 3, 4\) = 4)152 468 Q 30
(== 16384)18 F(00000000000000100000000000000000)6 E(vec\($_, 4, 4\) = 4)
152 480 Q 24(== 262144)18 F(00000000000000000010000000000000)6 E
(vec\($_, 5, 4\) = 4)152 492 Q 18(== 4194304)18 F
(00000000000000000000001000000000)6 E(vec\($_, 6, 4\) = 4)152 504 Q 12
(== 67108864)18 F(00000000000000000000000000100000)6 E
(vec\($_, 7, 4\) = 4)152 516 Q
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(vec\($_, 0, 4\) = 8)152 528 Q 54(== 8)18 F
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(== 128)18 F(00000001000000000000000000000000)6 E(vec\($_, 2, 4\) = 8)
152 552 Q 36(== 2048)18 F(00000000000100000000000000000000)6 E
(vec\($_, 3, 4\) = 8)152 564 Q 30(== 32768)18 F
(00000000000000010000000000000000)6 E(vec\($_, 4, 4\) = 8)152 576 Q 24
(== 524288)18 F(00000000000000000001000000000000)6 E
(vec\($_, 5, 4\) = 8)152 588 Q 18(== 8388608)18 F
(00000000000000000000000100000000)6 E(vec\($_, 6, 4\) = 8)152 600 Q 6
(== 134217728)18 F(00000000000000000000000000010000)6 E
(vec\($_, 7, 4\) = 8)152 612 Q
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(vec\($_, 0, 8\) = 1)152 624 Q 54(== 1)18 F
(10000000000000000000000000000000)6 E(vec\($_, 1, 8\) = 1)152 636 Q 42
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(vec\($_, 3, 8\) = 1)152 660 Q 12(== 16777216)18 F
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(== 2)18 F(01000000000000000000000000000000)6 E(vec\($_, 1, 8\) = 2)152
684 Q 42(== 512)18 F(00000000010000000000000000000000)6 E
(vec\($_, 2, 8\) = 2)152 696 Q 24(== 131072)18 F
(00000000000000000100000000000000)6 E(vec\($_, 3, 8\) = 2)152 708 Q 12
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(== 32)12 F(00000100000000000000000000000000)6 E(vec\($_, 1, 8\) = 32)
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