From: Nate Eldredge <neldredge AT hmc DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Prevent crash on free()
Date: 29 Feb 2000 11:23:43 -0800
Organization: InterWorld Communications
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To: djgpp AT delorie DOT com
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"Marcus" <mesthlm AT hem DOT passagen DOT se> writes:

> "Hans-Bernhard Broeker" <broeker AT acp3bf DOT physik DOT rwth-aachen DOT de> wrote:
> > I'm most definitely not kidding you...
> Okey, I understand...
> 
> > Essentially, yes, it is. Anyway, it is none of your function's...
> Hehe.... maybe it is... maybe it is...
> I know exactly what I'm doing. Can't you just tell me how? Please!

If you want to deal with deep innards of the system, then you get to
read the source.  Get djlsr203b.zip and start looking.
src/libc/ansi/stdlib/malloc.c should be a good start.

From that you should be able to find a mechanism to tell if a block
seems to be malloc'ed.  But for heaven's sake don't use it in released
software, because whatever you write WILL break with future versions.

-- 

Nate Eldredge
neldredge AT hmc DOT edu