From: Olaf van der Spek <olafvdspek@gmail.com>
Subject: Re: Atomic file data replace API
Date: Mon, 27 Dec 2010 16:53:49 +0100
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Cc: linux-fsdevel <linux-fsdevel@vger.kernel.org>,
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To: Amir Goldstein <amir73il@gmail.com>
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On Mon, Dec 27, 2010 at 2:20 PM, Amir Goldstein <amir73il@gmail.com> wrote:
> So as I wrote you on the previous thread, in Ext4 you can probably

FS-specific code should of course be avoided in normal apps.

> It is a more granular version of the exchangedata() BSD API mentioned
> in the previous thread:
> http://www.manpagez.com/man/2/exchangedata/
>
> So the atomic update is: write(tempfd); fdatasync(tempfd);
> exchangedata(tempfd, fd)

Except exchangedata is not (widely) implemented?
Don't you agree it's undesirable to lose meta-data?

Olaf