From:	"John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Help on memory!!!!!
Date:	Mon, 25 May 1998 16:08:56 -0400
Organization:	Two pounds of chaos and a pinch of salt.
Lines:	35
Message-ID:	<3569CFD8.6180@cs.com>
References:	<6kc3c7$cj6$1 AT news DOT IT DOT net>
NNTP-Posting-Host:	ppp107.cs.net
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Mauro Da Ros wrote:
> 
>   Ciao
> I'm desperate, I need help !!!
> I build a program that use degui and allegro;
> djgpp 2.01; gpp & libs 2.81
> It works under Windows 95 (well!), but...
> if I start in DOS mode, run cwsdpmi and run...
> it crash on the beginning with a
> 
> SEGSEGV
> Page fault at xxxxx error 0004
> etc...

This kind of error usually indicates some form of illegal memory access,
such as a rogue pointer, or occasionally a stack overflow or overwrite. 
There are some forms of these program bugs that Windows 95's DPMI host
does not trap, but cwsdpmi does.  It's also possible that it's caused by
an unlocked interrupt handler, although that would be _more_ likely to
occur under Windows 95, not less.

Look in the DJGPP Frequently Asked Questions list for the chapter on
debugging.  There, you can see how to decode that crash traceback into
something that will tell you where in your program the error occurred so
you can go back and debug it.  If you can't figure out the problem on
your own, post sample code from the vicinity of the crash location along
with a complete symified traceback here on the newsgroup.

-- 
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|      John M. Aldrich       |"A competent and self-confident person|
|       aka Fighteer I       | is incapable of jealousy in anything.|
|   mailto:fighteer AT cs DOT com   | Jealousy is invariably a symptom of  |
| http://www.cs.com/fighteer | neurotic insecurity."  - Lazarus Long|
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