Hello monks,

I have a DLL, from which I want to call a function with the following signature (as specified in the .h file that comes with the DLL): 
short WINAPI foo(short a, short b, short c, short d)

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Importing (specifying SHORT as the type of all arguments in the new 'C declaration parsing' version, or 'ssss' in the old style) with Win32::API::Import seems to go fine. However, when I actually call the imported function, I get an access violation message box.

Curiously, when I declare the arguments to be integers ('iiii'), there's no access violation, although I'm still not sure I get back the same answer.

1) Has anyone run into such a problem ? What can cause it ?

2) How is the call actually executed with Win32::API, re argument packing ? Are they all appended into one big lump of bytes ?

3) My DLL comes from a 3rd party library for controlling a certain PCI card. They supply the DLL, the .h files and a .LIB import file for simpler linking from C/C++. C++ linking of this DLL works fine, and according to them it should also work without problems in VB, Delphi and LabView. So I suppose nothing should prevent it from working in Perl with Win32::API ? Should the DLL be compiled in some special way to work with Win32::API, or does it work with all DLLs ? Thanks in advance

In reply to Win32::API and 'short' arguments by spurperl

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