Path: utzoo!utgpu!cunews!bnrgate!bwdls58!mlord
From: mlord@bwdls58.bnr.ca (Mark Lord)
Newsgroups: comp.os.msdos.programmer
Subject: Re: How can a TSR detect if it has been installed?
Message-ID: <7161@bwdls58.bnr.ca>
Date: 26 Jun 91 15:14:36 GMT
References: <1991Jun23.145337.20537@netcom.COM> <4944@gumby.Altos.COM> <1991Jun24.083508.6970@donau.et.tudelft.nl>
Sender: mlord@bwdls58.bnr.ca
Reply-To: mlord@bwdls58.bnr.ca (Mark Lord)
Organization: Bell-Northern Research, Ottawa, Canada
Lines: 15

In article <1991Jun24.083508.6970@donau.et.tudelft.nl> kooijman@duteca.et.tudelft.nl (Richard Kooijman) writes:
<jesse@gumby.Altos.COM (Jesse Chisholm AAC-RjesseD) writes:
<>| >How can it prevent itself from being re-installed?  I know programs such as
<
<>Many TSRs chain their interrupt and so it might be installed but no longer
<>be the first in the chain.  A way of checking for the signature you mention
<>that gets around this is to check at that offset for ALL segments from 0000

... various kludges from the dark ages omitted ...

Hey guys!  Ain't this what the "multiplex" interrupt was designed for ??

Check it out.

-ml