Dear D Users

I have now managed to get a dll function called from D, however I get an access violation when I actually make the call, I presume this is due to incorrect calling conventions. The code I use at the moment is below, I have taken the usual C approach in defining a typedef for the C function pointer, then declaring a variable to that type. However, in D one cannot specify the calling convention in the typedef. I assume therefore that this is not the way to do it. An earlier poster gave an example of how he did it, but I didn't quite understand the use of the alias keyword in the example.

Any suggestions, gratefully accepted!

Herbert Sauro

import std.c.stdio;
import std.c.windows.windows;

typedef int (* ptr_SBWCREATEMODULEIMPL) (char* ModuleName, char* DisplayName,
int SBWModuleManagementType, char* helpStr);

ptr_SBWCREATEMODULEIMPL SBWCreateModuleImpl;

int main ( char [] [] args ) {

HMODULE LibHandle;

printf ("Start Program\n");
LibHandle = LoadLibraryA ("sbw.dll\0");
printf ("LibHandle = %X\n", LibHandle);
SBWCreateModuleImpl = (ptr_SBWCREATEMODULEIMPL) GetProcAddress (LibHandle,
"SBWCreateModuleImpl\0");
printf ("SBWCreateModuleImpl Handle = %X\n", SBWCreateModuleImpl);

SBWCreateModuleImpl ((char *) "dsbw\0", (char*)"D language\0", 0, (char*)"\0");
getchar();
return 0;
}

firefly@fssc.demon.co.uk wrote:
> Dear D Users
> 
> I have now managed to get a dll function called from D, however I get an access
> violation when I actually make the call, I presume this is due to incorrect
> calling conventions. The code I use at the moment is below, I have taken the
> usual C approach in defining a typedef for the C function pointer, then
> declaring a variable to that type. However, in D one cannot specify the calling
> convention in the typedef. I assume therefore that this is not the way to do it.
> An earlier poster gave an example of how he did it, but I didn't quite
> understand the use of the alias keyword in the example.
> 
> Any suggestions, gratefully accepted!
> 
> Herbert Sauro
> 
> import std.c.stdio;
> import std.c.windows.windows;
> 
> typedef int (* ptr_SBWCREATEMODULEIMPL) (char* ModuleName, char* DisplayName,
> int SBWModuleManagementType, char* helpStr);
> 
> ptr_SBWCREATEMODULEIMPL SBWCreateModuleImpl;
> 
> int main ( char [] [] args ) {
> 
> HMODULE LibHandle;
> 
> printf ("Start Program\n");
> LibHandle = LoadLibraryA ("sbw.dll\0");
> printf ("LibHandle = %X\n", LibHandle);
> SBWCreateModuleImpl = (ptr_SBWCREATEMODULEIMPL) GetProcAddress (LibHandle,
> "SBWCreateModuleImpl\0");
> printf ("SBWCreateModuleImpl Handle = %X\n", SBWCreateModuleImpl);
> 
> SBWCreateModuleImpl ((char *) "dsbw\0", (char*)"D language\0", 0, (char*)"\0");
> getchar();
> return 0;
> }
> 
> 

Did you try using extern (C)?

news://news.digitalmars.com:119/c76bn6$at5$1@digitaldaemon.com

-[Unknown]

Yes I did, it doesn't work because it appears I can't declare a function pointer using extern (C) which is what I need to do when I call GetProcAddress.

Herbert

>
>Did you try using extern (C)?
>
>news://news.digitalmars.com:119/c76bn6$at5$1@digitaldaemon.com
>
>-[Unknown]

On Tue, 4 May 2004 06:54:06 +0000 (UTC), firefly@fssc.demon.co.uk
wrote:

>
>Yes I did, it doesn't work because it appears I can't declare a function pointer using extern (C) which is what I need to do when I call GetProcAddress.
>
>Herbert
>
>>
>>Did you try using extern (C)?
>>
>>news://news.digitalmars.com:119/c76bn6$at5$1@digitaldaemon.com
>>
>>-[Unknown]
>

extern(Windows) works !!
see the util8 dynloader/winmm lib on
http://www.geocities.com/one_mad_alien/dcode/

I quite happily call timeGetTime from winmm.dll with explict loading
(which is extern(Windows) )
extern(C) {
	alias int function (int, int) cfuncPtr;
}
should be the C equiv of
typedef __cdecl int (*cfuncPtr)(int, int);
(__cdecl might be in the wrong place I forget such things! but you
know what I mean)
then
cfuncPtr func = cast(cfuncPtr)GetProcAddress( hmodule, "myfunc" );
int i = func(1, 2);
should work .....

Mike.