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From:	"Gerrit van Niekerk" <gerritvn AT gpvno DOT co DOT za>
Organization:	GPvNO
To:	tim DOT nicholson AT skyforcekent DOT com
Date:	Fri, 23 Mar 2007 21:32:26 +0200
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Subject:	Re: protecting program memory
CC:	djgpp AT delorie DOT com
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On 23 Mar 2007 at 4:16, tim DOT nicholson AT skyforcekent DOT co wrote:

> Is there an easy way to protect the memory used to store the program
> op codes from a rogue memory write from within the application? I have
> a large (100,000+ line) DJGPP application which sometimes crashes with
> SIGILL - It would seem the program is cannibalizing itself! In order
> to find how this is happening, I would like to protect the entire
> block of memory that contains the application code so that an
> exception occurs at the point the corruption occurs rather than the
> point that the corrupted code is executed.
 
I certainly thought code would be protected, but it is not - I have just tested it. 
What is the reason for that?

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