From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: page fault and prob. w/ free()
Date:	Wed, 02 Feb 2000 21:23:22 +0200
Organization:	NetVision Israel
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To:	djgpp AT delorie DOT com
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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

No, a Page Fault has nothing to do with the cache.  Take a look at section
12.2 of the DJGPP FAQ list (v2/faq230b.zip from the usual DJGPP sites), it
explains what a Page Fault is.

> 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.

Crashes inside `free' are usually a sign of code that overruns (writes beyond
the end of) allocated buffers.  Section 9.2 of the FAQ has more about this
issue; please read it.

> 
> any suggestions of why free() wouldn't be working?
> 
> thanks,
> Darren

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