Win32::API accessing DLL

ganeshlin has asked for the wisdom of the Perl Monks concerning the following question:

Hi, I am trying to use a procedure exported by a .dll. I am using Win32::API. $function = new Win32::API('dllfile.dll', 'functionname', 'P','I') || die $!; This returns "The specified procedure could not be found." I tried using dumpbin /exports dllfile.dll I got the same function name but with a suffix _ and prefix @4 _functionname@4 Looking forward for a help in this.

Comment on Win32::API accessing DLL

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Re: Win32::API accessing DLL by philiprbrenan (Monk) on Sep 07, 2012 at 13:19 UTC
Windows has multiple calling conventions for functions. I believe the DLL is exposing different entry points to support these conventions. Please see: http://unixwiz.net/techtips/win32-callconv.html#conv	[reply]
Re: Win32::API accessing DLL by Corion (Patriarch) on Sep 07, 2012 at 12:15 UTC
So, have you tried to import that function using its mangled name? What happened?	[reply]
Re: Win32::API accessing DLL by bulk88 (Priest) on Sep 08, 2012 at 00:24 UTC
Use the decorated name. MS DLLs are special since they were all made with DEF files where the names are plain and undecorated. @4 means your function takes one 32 bit parameter and is stdcall. cdecls dont have a @12345.	[reply]
Re: Win32::API accessing DLL by nikosv (Deacon) on Sep 08, 2012 at 13:12 UTC
use dependency walker to load your dll and examine it. Also check "How do I view the parameter and return types of a function?" in the faq	[reply]
Re: Win32::API accessing DLL by Anonymous Monk on Sep 07, 2012 at 21:02 UTC
Be very careful that upper/lower case matches exactly...	[reply]