Hi, got a problem with calling a simple c++ dll from vb, always got error
"bad calling convention", all param-types seem to be correct :(

any ideas ?

thx, Lasse
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begin 666 dlltest.zip
<encoded_portion_removed>

Did you declare your C functions with  _stdcall ???

Don't post binary Zip files to the newsgroup when all you've got is 3 simple
files of source code.  Paste in your message or on a web page in text.
Viruses are spread by binaries and most people probably won't even look at
your problem because of that.

Anyway, I know nothing about C++.  However, if I were you, I wouldn't
delcare the function in Visual Basic with Alias "#3".  I'm not sure a
function can be called that way.  Instead, use the actual name of the
function.  I'm not sure, but from your C source, it looks like you are
actually trying to run "myDllFunc" or something like that.

--
Howard Henry 'Gawyn Ballpeen' Schlunder
Gawyn Developments; Core developer
http://venus.ajusd.org/~hschlund/

I have the same problem when I try and pass more than one variable

ie:

this works:

DLL(mydll):

#include <stdio.h>

#define DllExport __declspec( dllexport )
extern "C" DllExport long myfun(long x);
extern "C" DllExport long myfun(long x)
{
return (x + 200);

//  this passes a value from VB as x to this VCpp 5.0 dll (w/
//_stdcall). then returns x + 200 to VB as a long.

VB part:

    Private Declare Function myfun Lib _
        "C:\temp\mydll.dll" _

        (ByVal x As Long) As Long

But this one does not work for me.

DLL2(mydll)::

#include <stdio.h>

#define DllExport __declspec( dllexport )
extern "C" DllExport long myfun(long x, long y);
extern "C" DllExport long myfun(long x, long y)
{
return (x + y + 200);

//  this passes 2 values from VB as x & y  to this VCpp 5.0 dll (w/
//_stdcall). then should returns x +  y + 200 to VB as a long.  But I
get the dll does not support this function....

VB part:

    Private Declare Function myfun Lib _
        "C:\temp\mydll.dll" _

        (ByVal x As Long, ByVal y As Long) As Long

I hope this helps..  I am stuck also, but only when there are more
than one variable to pass..

If you like I can post explicit directions how to make the DLL..

Garrett

ok..  here is the fix:

DLL2(mydll)::

#include <stdio.h>

#define DllExport __declspec( dllexport )
extern "C" DllExport long myfun(long x, long y);
extern "C" DllExport long myfun(long x, long y)
{
return (x + y + 200);

//  this passes 2 values from VB as x & y  to this VCpp 5.0 dll (w/
//_stdcall). then should returns x +  y + 200 to VB as a long.  But I
get the dll does not support this function....

VB part:

****  here is the problem.  for 2 longs that is 8 bytes long not 4!

    Private Declare Function myfun Lib _
        "C:\temp\mydll.dll" _

        (ByVal x As Long, ByVal y As Long) As Long

hope this helps..

Garrett