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Date: Tue, 29 Jan 2002 01:56:27 -0500
From: Christopher Faylor <cgf AT redhat DOT com>
To: cygwin-developers AT cygwin DOT com
Subject: Re: fork() idea
Message-ID: <20020129065627.GA30010@redhat.com>
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References: <04ce01c1a72e$2c597940$0200a8c0 AT lifelesswks> <NCBBIHCHBLCMLBLOBONKOEMNCJAA DOT g DOT r DOT vansickle AT worldnet DOT att DOT net>
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On Tue, Jan 29, 2002 at 12:53:10AM -0600, Gary R. Van Sickle wrote:
>What about avoiding fork() entirely?  I'm of course not talking about a general
>solution, but take sh for example; would it be possible to write a shell that
>simply never forks (or has it already been done)?  That alone would be a massive
>win.  Seems that one could simply (he sez) maintain a state stack where each
>time you see a "var=$(echo something | somethingelse)", instead of forking you'd
>just push a new shell state on the stack, spawn the commands, do the piping and
>other shell-things in the same process, pop the stack and Bob's yer uncle, no
>fork overhead.
>
>Or am I missing something fundamental?

This is pretty much what ash + cygwni + vfork do now, more or less.

cgf