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Date: Thu, 31 Jul 2008 07:58:03 -0700
From: Chris Wedgwood <cw@f00f.org>
Subject: Re: [Qemu-devel] PATCH: Control over drive open modes for backing file
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To: qemu-devel@nongnu.org

On Thu, Jul 31, 2008 at 02:46:55PM +0100, Paul Brook wrote:

> > +#define BDRV_O_RDONLY ? ? ?0x0001 /* Force read-only */
> > +#define BDRV_O_WRONLY ? ? ?0x0002 /* Force writeable, no fallback */
> > +#define BDRV_O_RDWR ? ? ? ?0x0003 /* Try writeable, fallback to read-only
> > */
> 
> This is IMHO really misleading.  Normal O_* are not bitflags. The code uses 
> these as bitflags sometimes, which means your descriptions are contradictory.

Also the names aren't very intuitive, since BDRV_O_WRONLY really is
read-write not write-only.