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Date: Tue, 22 Nov 2011 12:36:59 +0100
From: Christoph Hellwig <hch@lst.de>
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Subject: Re: [Qemu-devel] [v9 Patch 6/6]Qemu: raw posix implementation
	of	reopen functions
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Supriya Kannery <supriyak@linux.vnet.ibm.com>, qemu-devel@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>, supriya kannery <supriyak@in.ibm.com>, Christoph Hellwig <hch@lst.de>

On Tue, Nov 22, 2011 at 11:32:42AM +0000, Stefan Hajnoczi wrote:
> Are you sure POSIX guarantees that O_DIRECT can be changed with
> F_SETFL?  I didn't find any statement in the specification.  It is
> possible that this code compiles but does not actually work on
> non-Linux OSes.  Did you run tests?

O_DIRECT is a non-posix extention, and semantics of it will differ
greatly between the operating systems implementing it.