Date: Wed, 2 Feb 2000 18:09:44 +0100 (MET)
From: Gisle Vanem <giva AT bryggen DOT bgnett DOT no>
To: djgpp AT delorie DOT com
Subject: Re: page fault and prob. w/ free()
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On 2 Feb 2000 deisenzi AT d DOT umn DOT edu wrote:

> I am causing a  run-time error in the form of a page fault.  I thought
> a page fault was a miss on the cache so I am not sure how I'm causing
> it but the offending line of code is...
> free(data_buffer);
> 
> where data_buffer has been declared as follows...
> unsigned char *data_buffer;
> 
> and allocated memory using malloc() before free is called.
> 
> any suggestions of why free() wouldn't be working?

It 99% certain that you overwrite some memory in front of 'data_buffer'.
free/malloc uses an small area there for various "house-keeping".

> 
> thanks,
> Darren
> 

Gisle V.