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Date: Tue, 5 Aug 1997 04:49:53 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199708041849.EAA10329@godzilla.zeta.org.au>
To: bde@zeta.org.au, sef@Kithrup.COM, tqbf@enteract.com
Subject: Re: Proposed alternate patch for the rfork vulnerability
Cc: security@FreeBSD.ORG
Sender: owner-freebsd-security@FreeBSD.ORG
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>Note that exit closes file descriptors.  So I guess exit should close
>all file descriptors for all processes, huh?

Only completely shared ones :-).

My test program had its stderr closed when the (non-execed) child
process exited.  All descriptors get closed.  Cooperating processes with
completely shared descriptors need to handle this somehow if one of them
exits and others want to keep running.  Exec doesn't really affect the
problem - processes can still cooperate after exec.

Bruce