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Subject: Re: [Qemu-devel] [PATCH 2/9] struct iovec is now universally available
From: Mark McLoughlin <markmc@redhat.com>
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Date: Wed, 15 Apr 2009 18:25:09 +0100
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To: Christoph Hellwig <hch@lst.de>
Cc: Jan Kiszka <jan.kiszka@siemens.com>, Anthony Liguori <aliguori@us.ibm.com>, qemu-devel@nongnu.org

On Wed, 2009-04-15 at 18:55 +0200, Christoph Hellwig wrote:
> On Wed, Apr 15, 2009 at 05:29:22PM +0100, Mark McLoughlin wrote:
> > struct iovec is now defined in qemu-common.h if needed, so we don't need
> > the tap code to handle !defined(HAVE_IOVEC).
> 
> But is the writev system call also universally available?

Fair point.

I don't know of anywhere that qemu currently builds where writev() isn't
available ... do you?

>>From looking at the history, I got the impression that HAVE_IOVEC was
only for windows and that doesn't use this code.

Also, if it is something we want to handle, then we should do it by
checking for writev() in configure and using HAVE_WRITEV

Cheers,
Mark.