Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!natinst!sequoia!rpp386!jfh
From: jfh@rpp386.Dallas.TX.US (John F. Haugh II)
Newsgroups: comp.unix.wizards
Subject: Re: What kinds of things would you want in the GNU OS?
Summary: Please don't trash my stack!
Message-ID: <16603@rpp386.Dallas.TX.US>
Date: 31 May 89 04:08:07 GMT
References: <106326@sun.Eng.Sun.COM> <31756@bu-cs.BU.EDU> <8565@chinet.chi.il.us> <31965@bu-cs.BU.EDU> <4347@ficc.uu.net>
Reply-To: jfh@rpp386.cactus.org (John F. Haugh II)
Organization: River Parishes Programming, Plano TX
Lines: 16

In article <4347@ficc.uu.net> peter@ficc.uu.net (Peter da Silva) writes:
>An efficient version of threads would not even duplicate the stack area...
>instead the child would have a virgin stack, wit its starting address
>passed from the parent. It's highlt desirable to make thread creation
>a cheap process.

You have to duplicate the stack - even if you only duplicate it via
a copy-on-write mechanism.

As you unwind stack frames in either thread, you would reach a point
where you start trashing the stack frames of the either thread.
-- 
John F. Haugh II                        +-Button of the Week Club:-------------
VoiceNet: (512) 832-8832   Data: -8835  | "AIX is a three letter word,
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