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Date: Sun, 18 Jan 2009 14:39:41 +0200
From: Uri Lublin <uril@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] qemu-img: adding a "-F base_fmt" option
	to "qemu-img create -b"
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: qemu-devel@nongnu.org

Anthony Liguori wrote:
>> From: Uri Lublin <uril@redhat.com>
>>
>> If the user specifies the backing file format,
>> then when opening the backing file, there is no need
>> to probe the (backing file) image to figure out its format.
>>
>> This follows my previous patch implementing fmt:FMT: prefix for backing
>> filename.
>>   
> 
> But how does this work in the absence of supporting fmt:FMT?  Does this 
> imply that the other patch is needed too?
> 

Yes, This patch only has meaning if the fmt:FMT: patch is accepted.

Its purpose is to give the user a way to specify the backing file format ('-F 
FMT') without using specific implementation details (prefixing the backing-file 
filename with 'fmt:FMT:' )

Suggested by Daniel P. Berrange.

Thanks,
     Uri.