From owner-freebsd-arch@FreeBSD.ORG  Sun Apr 13 07:05:54 2008
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To: Jeff Roberson <jroberson@jroberson.net>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sat, 12 Apr 2008 13:51:15 -1000."
	<20080412132457.W43186@desktop> 
Date: Sun, 13 Apr 2008 07:05:51 +0000
Message-ID: <18354.1208070351@critter.freebsd.dk>
Sender: phk@critter.freebsd.dk
Cc: arch@freebsd.org
Subject: Re: f_offset 
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In message <20080412132457.W43186@desktop>, Jeff Roberson writes:

>It's worth discussing what posix actually guarantees for f_offset as well 
>as what other operating systems do.

I think DWIM is quite easily defined here:  concurrent access only
makes sense with pwrite[v](2)/pread[v](2).

The non p-prefix versions should always be serialized, because there
is know way of knowing where they read/write if you don't.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.