Venu
13th April 2005 18:57 UTC

call __stdcall function in WIn32 dll from NSIS
Hi All,

I have created a Win32 DLL with a function exported as -

#define MY_API extern"C" __declspec(dllexport)
MY_API int __stdcall myFunc(char *path);

When i call this function from NSIS it is failing. Though its entering the DllMain the function does not get called.

If i remove remove __stdcall and compile the DLL with __cdecl calling convention it works.

What is the work around for calling functions with __stdcall calling convention

Rgds
Venu

kichik
14th April 2005 18:15 UTC

How exactly do you call it? The System plug-in uses the stdcall calling convention by default.

Venu
15th April 2005 06:09 UTC

Hi Kichik,

Function Declaretion in Dll:
#define MY_API extern"C" __declspec(dllexport)
MY_API int __stdcall myFunc(char *path);

Calling the function from NSIS:
StrCpy $0 "NSIS"
System::Call '$EXEDIR\MyDll::myFunc(t)i(r0).r1'

Iam using VC++6 and NSIS 2.06

Takhir
15th April 2005 07:38 UTC

Order of args for one parameter may be not so important..
BTW what name shows Dependency Walker for yor dll?

Venu
18th April 2005 06:40 UTC

Hi Takhir,

The dependency walker shows the name:
int myFunc(char *)
( Decorated Name: ?myFunc@@YGHPAD@Z )

kichik
19th April 2005 18:22 UTC

That's not good. NSIS uses the name shown by Dependency Walker (?myFunc@@YGHPAD@Z). Add extern "C" before the function definition if you're compiling a C++ file. For example:

extern "C" void myFunc(char *);