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Date: Wed, 15 Apr 2009 19:27:43 +0200
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [Qemu-devel] [PATCH 2/9] struct iovec is now universally available
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To: Mark McLoughlin <markmc@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>, Anthony Liguori <aliguori@us.ibm.com>, Christoph Hellwig <hch@lst.de>, qemu-devel@nongnu.org

On Wed, Apr 15, 2009 at 06:25:09PM +0100, Mark McLoughlin wrote:
> 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.

Windows would be my first guess, but if that code isn't built for
windows the point is moot.

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

Agreed.