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Date: Tue, 1 Sep 2009 18:04:09 +0200
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [Qemu-devel] [PATCH 2/4] block: use fdatasync instead of fsync
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To: Blue Swirl <blauwirbel@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>, qemu-devel@nongnu.org

On Tue, Sep 01, 2009 at 06:59:46PM +0300, Blue Swirl wrote:
> On Mon, Aug 31, 2009 at 11:17 PM, Christoph Hellwig<hch@lst.de> wrote:
> >
> > If we are flushing the caches for our image files we only care about the
> > data (including the metadata required for accessing it) but not things
> > like timestamp updates. ??So use fdatasync instead of fsync to implement
> > the flush operations.
> 
> > - ?? ??fsync(s->fd);
> > + ?? ??fdatasync(s->fd);
> 
> There is no fdatasync outside of Linux, not in OpenBSD and mingw32 at
> least. But you could add a probe for it to configure.

Oh, okay.  Kinda sad that people still don't implement useful inteface
that have been in Posix for a long time.