Subj : Re: Creating DLLs with Borland C++ 5.5 For Use In VB (Not COM or OLE)
To   : borland.public.cpp.borlandcpp
From : "David Cravey" <craveyjunk@vivicominc.com>
Date : Sat Oct 04 2003 02:13 pm

Dennis,

Thank you sooo much for your help.  I have not figured it all out yet, but I
am heading in the right direction.  I am still getting a VB error 48 "Cannot
find dll", and when I downloaded the code you mentioned in windows
developers journal I had the same results.  I am guessing I am not using
some command line option that I need.  I will also try the code on my
Borland C++ 5 compiler.  (I am not using it right now because I have a hard
time making it compile both windows programs and 186 Dos programs, we have
an embedded 186 I have to develope for.)

Thanks again!!!

Thanks,
David

----- Original Message ----- 
From: "Dennis Jones" <djones@nospam.com>
Newsgroups: borland.public.cpp.borlandcpp
Sent: Friday, October 03, 2003 2:00 PM
Subject: Re: Creating DLLs with Borland C++ 5.5 For Use In VB (Not COM or
OLE)


>
> "David Cravey" <craveyjunk@vivicominc.com> wrote in message
> news:3f7cd162@newsgroups.borland.com...
> > Hi,
> >
> > I am wanting to create a few very simple DLLs to export a few functions
> (not
> > classes) that I can use in Visual Basic.  My company requires me to use
> > Visual Basic, but sometimes I need to create a few processing routines
> that
> > are not impossible but very slow in VB.  If anyone has an example C file
> > which exports one or more functions which can be used by VB then I would
> be
> > very appreciative.
>
> As Ed has already said, this is indeed the wrong newsgroup for questions
> abot the free Borland compiler, however the information you need should be
> the same for all Borland compilers, so I will provide it here.
>
> There is a great article in the August 1996 issue of the Windows
Developer's
> Journal which addresses the issue of creating generic DLL's that can be
used
> by any Windows application.  Essentially, it boils down to making sure the
> calls are decorated properly and have the right calling sequence.
>
> In your DLL header file:
>
> /* Begin MyDll.h */
> #if !defined( _MYDLL_LIB_ )
> #define MYDLL_API extern __declspec( dllimport )  // make functions
> importable
> #else
> #define MYDLL_API extern __declspec( dllexport )  // make functions
> exportable
> #endif
>
> #define CALLSEQ __stdcall
>
> #ifdef __cplusplus
> extern "C" {
> #endif
>
> MYDLL_API void CALLSEQ SomeDLLFunc( void );
>
> #ifdef __cplusplus
> }
> #endif
> /* End MyDll.h */
>
>
> In your DLL source file:
>
> /* Begin MyDll.c[pp] */
> #define _MYDLL_LIB_  // makes the functions exportable
> #include "MyDll.h"
>
> #ifdef __cplusplus
> extern "C" {
> #endif
>
> MYDLL_API void CALLSEQ SomeDLLFunc( void )
> {
>   // do something
> }
>
> #ifdef __cplusplus
> }
> #endif
> /* End MyDll.c[pp] */
>
>
> Then, to use the functions in the DLL, just include the header:
>
> #include "MyDll.h"
> int main( void )
> {
>   SomeDLLFunc();
>   return 0;
> }
>
> Hope this helps,
>
> - Dennis
>
>

.