From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: gdb problem or just silly me - please help
Date:	Thu, 27 Apr 2000 18:18:55 +0200
Organization:	NetVision Israel
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To:	djgpp AT delorie DOT com
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"nimrod a. abing" wrote:
> 
> for those who are curious, here's how to do it (crash
> the program using printf ;-)
[snip] 
> Exiting due to signal SIGSEGV
> General Protection Fault at eip=00001629
> eax=20776f4e ebx=00008318 ecx=00000000 edx=20776f4e esi=00000054 edi=0000f148
> ebp=00683fe0 esp=00683fc8 program=D:\PROJECTS\DJGPP\QUICKIES\TEST.EXE
> cs: sel=012f  base=8318a000  limit=00683fff
> ds: sel=0137  base=8318a000  limit=00683fff
> es: sel=0137  base=8318a000  limit=00683fff
> fs: sel=010f  base=000121d0  limit=0000ffff
> gs: sel=0147  base=00000000  limit=0010ffff
> ss: sel=0137  base=8318a000  limit=00683fff
> App stack: [00684000..00604000]  Exceptn stack: [0000f0a8..0000d168]
> 
> Call frame traceback EIPs:
>   0x00001629 _main+37
>   0x00002a02 ___crt1_startup+178

This crash obviously comes from Windows (observe the selectors values and the
large base address).  Windows doesn't support the NULL dereference
protection, and so crashes much later, inside `main' (see the EAX register
that holds ASCII text instead of a pointer?).  It doesn't even mention
printf.

In contrast, on DOS with CWSDPMI, you will get a Page Fault instead of a GPF,
and the traceback will point exactly to the place where the offending code
lives.

> How to free up at least 300 MB of hard disk
> space (as seen from the MS-DOS prompt):
> 
> C:\>deltree c:\windows
> Delete directory "Windows" and all its subdirectories? [yn] y
> Deleting Windows...

The above seems to suggest that you yourself do use Windows ;-)

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