From owner-freebsd-hackers  Sat Sep 28 09:06:51 1996
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To: guido@gvr.win.tue.nl (Guido van Rooij)
cc: dyson@FreeBSD.org, FreeBSD-hackers@FreeBSD.org
Subject: Re: stack 
In-reply-to: Your message of "Sat, 28 Sep 1996 18:03:38 +0200."
             <199609281603.SAA05989@gvr.win.tue.nl> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Sat, 28 Sep 1996 09:07:58 -0700
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>David Greenman wrote:
>> >I used exactly this program:
>> >main() {
>> >	char buf[1000];
>> >
>> >	write(1, buf, 1000);
>> >}
>> >
>> >The resulting file did not conatin only zero's. I think this is weird.
>> 
>>    You might think it's weird, but it is not a bug or even unexpected. Stack
>> space is not guaranteed to be initialized to any particular value.
>
>I thought this was guarantueed because when the `feature' was dropped
>to many programs discontinued working..

   Huh? Not that I'm aware of. I think you might be confusing .bss allocated
space which is created as zero-filled. If you move your variable declaration
above to outside of main(), the space will be allocated from .bss and thus
will be zero-filled.

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project