From: Hans-Bernhard Broeker <broeker AT acp3bf DOT physik DOT rwth-aachen DOT de>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: page fault and prob. w/ free()
Date: 2 Feb 2000 19:07:02 GMT
Organization: Aachen University of Technology (RWTH)
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References: <879l3i$m61$1 AT news DOT d DOT umn DOT edu>
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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 

Nah, it's a lot more serious than that. You missed not the cache, but
the addressable range of memory for that process. You fell into a hole
in the middle of address space (an 'unmapped page').

> free(data_buffer);

free() calls killing the application with a page fault almost always
mean that you've overwritten memory outside the bounds of some block
you allocated (array index over-run, or under-run), corrupting
malloc()'s internal book-keeping data.


-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.