From: "David Schwartz" <davids@webmaster.com>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-kernel@vger.kernel.org>
Subject: RE: Dumb question: Why are exceptions such as SIGSEGV not logged
Date: Tue, 19 Aug 2003 13:01:26 -0700
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> Correction...
>
> _exit(2).
>
> There is no exit(2); I was talking about _exit(2) and you're talking
> about exit(3).
>
> _exit(2) *is* guaranteed to terminate a process immediately.
>
> 	-hpa

	If only it was so! I have direct practical experience that under
LinuxThreads, at least, it doesn't. SuSv3 allows _exit to flush open streams
and remove temporary files. Sadly, _exit, on many systems, acquire locks or
accesses process structures that might be corrupt whereas dereferencing a
NULL pointer does not.

	I have portable code that has a 'terminate this process immediately'
function. It started out calling '_exit' until we found platforms where that
resulted in a hang (say the thread calling _exit holds a non-recursive mutex
that the _exit function tries to acquire). So we kept inching our way up to
more and more extreme termination methods.

	DS


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