From: "Andrew Davidson" <andrew AT lemure DOT freeserve DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Calling C functions from machine code...
Date: Wed, 14 Apr 1999 01:21:03 +0100
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

I'm trying to call a couple of simple functions written in C from within
some dynamically created machine code in one of my programs.
All I know so far is that I can find the return value of the function
(assuming it is 32bits or less) in eax and that I should push all the
parameters of the function as 32bit values (incidentally, is eax clobbered
if the function is void?). However, I don't know what exactly I should be
pushing as simply pushing the parameters causes a sigill error after the
function has completed. Also what is left on the stack after the function
has finished?

Thanks for any help,
Andrew