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From: Zefram <zefram@tao.co.uk>
Message-Id: <199807161614.RAA32121@taos.demon.co.uk>
Subject: Re: rolling over high-traffic logfiles?
To: schaefer@brasslantern.com (Bart Schaefer)
Date: Thu, 16 Jul 1998 17:14:28 +0100 (BST)
Cc: zsh-users@math.gatech.edu, sweth@astaroth.nit.gwu.edu
In-Reply-To: <980716082633.ZM15563@candle.brasslantern.com> from "Bart Schaefer" at Jul 16, 98 08:26:32 am
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Bart Schaefer wrote:
>} mv should use rename() to atomically replace the log file, in which case
>} there is no race condition.
>
>Fair enough.  There are two or more filesystem operations necessary even
>if only only system call, but I suppose that's only a possible problem
>on a multiprocessor system.

POSIX.1 defines rename() to be atomic, as is historical practice.
On multiprocessor systems the kernel just has to take a little extra care.
POSIX.2 defines mv to behave as if it were calling rename().

-zefram