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Date: Wed, 20 Jul 2011 10:26:49 +0200
From: Jes Sorensen <Jes.Sorensen@redhat.com>
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Subject: Re: [Qemu-devel] live snapshot wiki updated
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To: "Daniel P. Berrange" <berrange@redhat.com>
Cc: "libvir-list@redhat.com" <libvir-list@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, Eric Blake <eblake@redhat.com>, QEMU Developers <qemu-devel@nongnu.org>, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

On 07/19/11 18:47, Daniel P. Berrange wrote:
> On Tue, Jul 19, 2011 at 04:30:19PM +0200, Jes Sorensen wrote:
>> On 07/19/11 16:24, Eric Blake wrote:
>>> Besides, I feel that having a well-documented file format, so that
>>> independent applications can both parse the same file with the same
>>> semantics by obeying the file format specification, is a good design goal.
>>
>> We all know that documentation is rarely uptodate, new features may not
>> get added and libvirt will never be able to keep up. The driver for a
>> file format belongs in QEMU and nowhere else.
> 
> This would be possible if QEMU to provide a libblockformat.so library
> which allowed apps to extract metadata from file formats using a stable
> API.

There is no reason for libvirt or any external process to mess about
with the internals of image files. You have the same problem if the
image file is encrypted.

Jes