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From: dmurdoch@watstat.waterloo.edu (Duncan Murdoch)
Newsgroups: comp.os.msdos.programmer
Subject: Re: Turbo C's Run Time Error Messages
Message-ID: <1990Oct2.130711.10315@maytag.waterloo.edu>
Date: 2 Oct 90 13:07:11 GMT
References: <6243@uceng.UC.EDU> <HOLLEN.90Oct1075122@akbar.megatek>
Sender: daemon@maytag.waterloo.edu (Admin)
Organization: University of Waterloo
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In article <HOLLEN.90Oct1075122@akbar.megatek> hollen@megatek (Dion Hollenbeck) writes:

(about tracking down code which writes to DS:0):

>You may want to eliminate the divide and conquer portion I suggest,
>but I would advise against it.  When I tried to to this the first
>time, a program which displayed its sign on screen in less than 2
>seconds took over 2 hours to display it.  The reason is that TD
>stores a copy of the area you wish to watch.  After every machine
>instruction, it stops and compares the stored memory with the actual
>memory.  You really don't want to do this.

If you're lucky enough to have a 386 or 486, you can save a lot of time by
running TD386 and setting a hardware breakpoint which breaks on a write to
that location.  Your program runs full speed until it gets there.
This works in TD 1.5; the details may have changed in TD 2.0.

Duncan Murdoch
dmurdoch@watstat.waterloo.edu