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Message-ID: <5587B696.10304@gmail.com>
Date: Mon, 22 Jun 2015 03:17:42 -0400
From: "Frank Sapone (emoaddict15 AT gmail DOT com)" <djgpp AT delorie DOT com>
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To: djgpp AT delorie DOT com
Subject: Detecting Windows NT in DJGPP
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Reply-To: djgpp AT delorie DOT com

Hey everyone,

Quake 1 has a rather simple test for detecting if it's being run on 
Windows 9x:

     __dpmi_regs                             r;

     r.x.ax = 0x160a;                /* Get Windows Version */
     __dpmi_int(0x2f, &r);

     if(r.x.ax || r.h.bh < 4)        /* Not windows or earlier than Win95 */
         <code>
     else
         <code>

I'd like to detect if the program is running in NTVDM/Win XP/etc.  I 
know you can check for WINDIR as an evironment string, but that could be 
unreliable
from someone with a bad autoexec.bat.

Is there any other way to detect if it's in an NT environment?

Frank