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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 22:24:22 -1000."
	<20080412221654.S959@desktop> 
Date: Sun, 13 Apr 2008 15:22:58 +0000
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Sender: phk@critter.freebsd.dk
Cc: arch@freebsd.org
Subject: Re: f_offset 
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In message <20080412221654.S959@desktop>, Jeff Roberson writes:

>> The non p-prefix versions should always be serialized, because there
>> is know way of knowing where they read/write if you don't.
>
>Well that's at odds with what the standard says and what others implement. 
>I think there is a clear case for serializing writes.  I don't see what 
>advantage we get from serializing reads.  The heavy cost of 
>synchronization should be justified by actual need.

If you don't serialize read(2) and readv(2), how do you know where
they read from ?

-- 
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.