| Subject: | Win32_API-0.55 can't handle doubles |
This is using Win32-API-0.55, Visual Studio 7.0, and perl 5.10.0 (built
from source using the same Visual Studio 7.0 compiler)
--- mydll.h ----
__declspec(dllexport) int my_int(int);
__declspec(dllexport) double my_double(int);
----------------
--- mydll.c ----
#include "mydll.h"
__declspec(dllexport) int my_int(int x) {
return x / 7;
}
__declspec(dllexport) double my_double(int x) {
return (double) x / 7;
}
----------------
Build the dll:
----------------
C:\_32\c>cl /LD mydll.c
Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 13.00.9466 for
80x86
Copyright (C) Microsoft Corporation 1984-2001. All rights reserved.
mydll.c
Microsoft (R) Incremental Linker Version 7.00.9466
Copyright (C) Microsoft Corporation. All rights reserved.
/out:mydll.dll
/dll
/implib:mydll.lib
mydll.obj
Creating library mydll.lib and object mydll.exp
C:\_32\c>
----------------
The perl script that attempts to access mydll.dll using Win32-API-0.55:
--- mydll.pl ---
use Win32::API;
use warnings;
$func1 = new Win32::API('mydll', 'my_int', 'N', 'N', '_cdecl');
$val = $func1->Call(123);
print "Val1: $val\n";
$func2 = new Win32::API('mydll', 'my_double', 'N', 'D', '_cdecl');
$val = $func2->Call(123);
print "Val2: $val\n";
----------------
Run mydll.pl:
----------------
C:\_32\c>perl mydll.pl
Val1: 17
Use of uninitialized value $val in concatenation (.) or string at
mydll.pl line 12.
Val2:
C:\_32\c>
----------------
Clearly the reported value for $val1 is correct, but not for $val2.
Cheers,
Rob