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From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.bugs.4bsd,comp.unix.wizards
Subject: Re: Shared file descriptors
Message-ID: <10341@smoke.BRL.MIL>
Date: 30 May 89 16:09:10 GMT
References: <1770@taux01.UUCP>
Reply-To: gwyn@brl.arpa (Doug Gwyn)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 13

In article <1770@taux01.UUCP> gil%taux01@nsc.COM (Gil Shwed) writes:
>		fork();
>		while((n = read(0, buf, 8192)) > 0)
>			write(1, buf, n);

This program has a race condition between the two processes,
even in the absence of kernel bugs.

>	The problem should be fixed by locking the inode before
>	taking the offset (This is the way SystemV does it).

Yeah, it's a problem, isn't it.  We begin to see why genuine
concurrent programming constructs are useful..