Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!emory!att!cbnewsh!rkl
From: rkl@cbnewsh.att.com (kevin.laux)
Newsgroups: comp.os.msdos.programmer
Subject: Re: Auto-detecting a mouse
Message-ID: <1990Dec19.202346.21225@cbnewsh.att.com>
Date: 19 Dec 90 20:23:46 GMT
References: <59797@brunix.UUCP>
Distribution: na
Organization: AT&T Bell Laboratories
Lines: 11

In article <59797@brunix.UUCP>, hleaves@ruby.vcu.edu (EAVES,HUGH) writes:
> I'm writing a program that uses some of the mouse driver's interrupt routines
> (int 33h). How do I check to see if a mouse driver is present on my system
> before I make any calls?

	Invoke Int 33h with AX set to zero.  Upon return, examine the value
of AX.  If it is still zero, then the Mouse hardware/software is not installed.
If AX is set to -1, then the Mouse hardware is installed and the Mouse driver
is loaded.

--rkl