From owner-freebsd-current  Wed Jul  4 16:31:57 2001
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Date: Thu, 5 Jul 2001 00:31:35 +0100 (BST)
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From: Richard Tobin <richard@cogsci.ed.ac.uk>
Subject: Re: system and (v)fork
To: Peter Jeremy <peter.jeremy@alcatel.com.au>,
	David Hill <djhill@novagate.net>
In-Reply-To: Peter Jeremy's message of Thu, 05 Jul 2001 08:17:03 +1000
Organization: just say no
Cc: freebsd-current@FreeBSD.ORG
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> vfork(2) [...] The child code
> between the fork() and subsequent exec() must be carefully written
> because any changes to memory (including stack) or open files will
> also be reflected in the parent.

Not open files: indeed, the main thing you typically want to do before
the exec() is opening, closing and duping files.  Stdio FILE
structures on the other hand are just like any other memory, so you
probably don't want to touch them (hence the warning in the man page
to use _exit() rather than exit()).

-- Richard


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