This is the mail archive of the
cygwin@cygwin.com
mailing list for the Cygwin project.
Re: Calling gcc built DLL from .NET (Visual Basic)
- From: Danny Smith <danny_r_smith_2001 at yahoo dot co dot nz>
- To: thoban at verbalogic dot com
- Cc: cygwin at cygwin dot com
- Date: Thu, 5 Jun 2003 10:21:04 +1000 (EST)
- Subject: Re: Calling gcc built DLL from .NET (Visual Basic)
From: "Thomas X. Hoban" <thoban at verbalogic dot com>
--------------------------------------------------------------------------------
> Does anyone have a good example that shows how to create a DLL using
> cygwin/gcc and call it using VB .NET? I am specifically interested in an
> example that shows how to pass a String variable. In the example that I
> show below, I am able to call a C function. I can successfully pass a long
> integer. But the string that I pass shows garbage in the called function.
>
> My dll code looks like...
>
>
> (test.c)
>
> #include <stdio.h>
> #include <wtypes.h>
>
> define EXPORT __declspec(dllexport)
>
> EXPORT int myTest(char *s1, long i1) {
>
> printf("Here is the string %s, here is the integer %ld.\n",s1, i1);
>
> }
>
>
I think VB wants stdcall symbols. Add WINAPI to above..
>
> I then compile as follows:
>
> $ gcc -c test.c
> $ gcc -shared -o test.dll test.o
and -Wl,--add-stdcall-alias when building dll to get undecorated symbol too.
I don't have a clue about char* -> STRING marshalling. I would have just used
BSTR.
Danny
http://mobile.yahoo.com.au - Yahoo! Mobile
- Check & compose your email via SMS on your Telstra or Vodafone mobile.
--
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Problem reports: http://cygwin.com/problems.html
Documentation: http://cygwin.com/docs.html
FAQ: http://cygwin.com/faq/