From: "Johnny Chan" <jchan AT paclink DOT net>
To: <djgpp AT delorie DOT com>
Subject: RE: Q: Want to know the starting address and size of my program
Date: Thu, 14 Oct 1999 17:58:41 -0700
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good suggestion, Shawn,

>>But there is another option, if you make the memory test be 
>>non-destructive. You can test a location by reading the old
>>value, changing the value, reading it back to make sure that
>>it truly did change, and then writing the original value back
>>when you are done, and in this case, as long as you don't
>>touch the specific few instructions that are making these

That's exactly what I have in mind. However, I still
have a hard time to figure out the location of that "critical"
code/data. I will try Eli's suggestion tonight.

>>checks (which can be just a small asm function that you have
>>direct control over), it doesn't matter if you stomp all over
>>the rest of your program. As long as you disable interrupts

Any DJGPP function to disable the interrupt?

>>and aren't running under any fancy OS, it should be pretty
>>safe to access whatever memory you like in this way.
--jC