There's a burried comment about this:
"If your callback is going to fork, you'd be advised to have the child:
$SIG{ALRM} = 'DEFAULT';
$SIG{CHLD} = 'DEFAULT';
This will prevent the child from inheriting the parent's handlers, and
possibly confusing any child calls to waitpid."
It's obviously better to be more defensive than that.
Apply the below patch, and the SIG usage then changes to
$SIG{TERM} = sub { $fork->kill_tree_all('TERM') if $fork &&
$fork->in_parent; die "Quitting...\n"; };
If this makes sense to you I'll push a new release with it plus related
documentation & test fixes.
Index: lib/Parallel/Forker.pm
===================================================================
--- lib/Parallel/Forker.pm (revision 64594)
+++ lib/Parallel/Forker.pm (working copy)
@@ -38,8 +38,8 @@
_labels => {}, # List of process objects, keyed by label
_runable => {}, # Process objects runable now, keyed by id
_running => {}, # Process objects running now, keyed *PID*
_in_child => 0, # In a child process, don't allow forking
_run_after_eqn => undef,# Equation to eval to determine if ready to launch
+ _parent_pid => $$, # PID of initial process creating the forker
max_proc => undef, # Number processes to launch, <1=any, +=that number
use_sig_child => undef, # Default to not using SIGCHLD handler
@_
@@ -50,6 +50,11 @@
#### ACCESSORS
+sub in_parent {
+ my $self = shift;
+ return $self->{_parent_pid}==$$;
+}
+
sub max_proc {
my $self = shift;
$self->{max_proc} = shift if $#_>=0;
@@ -305,7 +310,7 @@
use Parallel::Forker;
$Fork = new Parallel::Forker (use_sig_child=>1);
$SIG{CHLD} = sub { Parallel::Forker::sig_child($Fork); };
- $SIG{TERM} = sub { $Fork->kill_tree_all('TERM') if $Fork; die
"Quitting...\n"; };
+ $SIG{TERM} = sub { $Fork->kill_tree_all('TERM') if $Fork &&
$Fork->in_parent; die "Quitting...\n"; };
$Fork->schedule
(run_on_start => sub {print "child work here...";},
