Date: Sun, 17 Jan 1999 19:21:17 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender: eliz AT is
To: Corinne Merry <bmerry AT iafrica DOT com>
cc: djgpp AT delorie DOT com
Subject: Re: DJGPP, DOSEmu and IPX
In-Reply-To: <36A20B3B.D8AB5558@iafrica.com>
Message-ID: <Pine.SUN.3.91.990117191753.29555A-100000@is>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Reply-To: djgpp AT delorie DOT com


On Sun, 17 Jan 1999, Corinne Merry wrote:

> According to Ralf Brown's interrupt list, INT 2F/AX=7A00 should return
> 0xff in AL if IPX is installed, 0x00 otherwise. Under DOSEmu, debugging
> (with RHIDE) reveals that none of the registers in r are changed by the
> __dpmi_int call (I didn't check exactly, but I didn't see any change and
> AX definitely didn't change). However, if in debug (as in Windows 95,
> from the authors of edlin and debug) I assemble two lines to call this
> interrupt with AX=7a00 and trace it, then AL is set to 0xff (all of this
> is under DOSEmu).

The difference between __dpmi_int and your debug script is that the 
former goes through the DPMI interrupt 31h, while the latter issues
interrupt 2Fh directly.

You need to find out why does the IPX reply when Int 2Fh is issued 
directly, but not when it is issued via the DPMI service.

Perhaps DOSEmu doesn't let you communicate with the IPX via DPMI (just
speculating).