From: khan AT xraylith DOT wisc DOT edu (Mumit Khan)
Subject: finding out if main app is cygwin
16 Nov 1998 22:23:58 -0800
Message-ID: <9811170601.AA25995.cygnus.cygwin32.developers@modi.xraylith.wisc.edu>
To: cygwin32-developers AT cygnus DOT com

I'm too happy with my current hack of supporting non-cygwin apps loading
cygwin DLLs; the hack creates an alternate entry point that you have to
specify if the DLL will be loaded by non-cygwin apps. This is troublesome
since you'll have to know *how* the DLL was linked.

If a Cygwin DLL can somehow figure out (quickly) if the main app is
Cygwin, then we can do this via the single entry point without any/much
hassle. The DLL startup for non-cygwin apps will still be suboptimal
(eg., I don't know if fork works reliably), but at least the same DLL
will work for both cygwin and non-cygwin apps.

I believe that you can get a handle to the main executable with 
``GetModuleHandle (NULL, ...)'', but don't know an easy way to figure
out if the app is cygwin from that point on. 

I remember Chris Faylor working on something similar, so perhaps Chris
already has something? I did steal some code from Emacs/NT that did just 
that (maps the file into memory and looks at dependencies looking for
some DLL), but there has to be faster way.

Regards,
Mumit