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Message-ID: <3C4BA620.4050407@niles.de>
Date: Mon, 21 Jan 2002 06:24:48 +0100
From: "Mader, Alexander" <alexander DOT mader AT niles DOT de>
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To: Tim <tjbynum AT swbell DOT net>
CC: cygwin AT cygwin DOT com
Subject: Re: DLL And Visual Basic
References: <007401c1a1dc$86c1a800$fa34fea9 AT rineco DOT com>
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Hallo,

from my understanding during the development of DLLs for VB there are 
the following important things:

1. Compile with stdcall: VB uses the stdcall (Pascal) calling 
convebtion. Either hardcode it (_I_ wouldn't do that) or use the -mrtd 
with gcc.

2. When passing structs mind the sick padding convention in VB! They pad 
to 4byte! So you have to fill by hand your c/c++-struct to contain a 
multiple of 4bytes and compile with -fpack-struct.

NB: Additionally I compile with -fnative-struct. I found no 
documentation for this option (Could anybody explain?) but it is used 
for the gtk-port and sounds good to me :-)

Of course DllMainStartup... must be linked with the object files for the DLL

Best wishes,

Alexander.
-- 
Alexander Mader <alexander DOT mader AT niles DOT de>	Fon: +49-30-93033-636
NILES Werkzeugmaschinen GmbH			Fax: +49-30-93033-603
				www.niles.de



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