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Date: Fri, 13 Jul 2012 10:12:47 +0100
From: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
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Subject: Re: [Qemu-devel] [RFC] introduce a dynamic library to expose qemu
 block API
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>, Wenchao Xia <xiawenc@linux.vnet.ibm.com>, qemu-devel@nongnu.org

On Tue, Jul 10, 2012 at 09:18:01AM +0200, Paolo Bonzini wrote:
> Il 10/07/2012 07:37, Wenchao Xia ha scritto:
> >>
> >> For getting the other metadata about the disk image you mention, another
> >> possibility to is just make 'qemu-img info' return the data in a machine
> >> parseable format, ie JSON&  make a client API for extracting data from
> >> this JSON document.
> >>
> >   Thank u for the idea. The .so is introduced to let program access the
> > image more directly, parsing string is not so fast and it depends on
> > another program's stdout output, I hope to get a faster way.
> 
> I doubt you actually have profiled it.

I think speed is not the issue, instead it's just providing an API that
external programs can use.  Management tools, backup software, custom
administration tools, etc.  It's convenient to have an API.

Stefan