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From: James <James.McKenzie@citrix.com>
Subject: Re: [Qemu-devel] [PATCH 01/11] QMP: Introduce specification file
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To: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

> now providing there was a maintained library out there, would you use it ?
> or do you have more concerns that were unanswered ?

I have exactly one concern. If Qemu grows an RPC protocol, it will be used 
by a large number of other programs to control qemu. This is a good thing.
But it is important that such a system 

1) either supports some sort of introspection so that the functions and
   their arguments can be divined by the external program without knowing
   which particular version of qemu it is talking to.

2) and/or supports an IDL so that the interface is properly documented in
   something other than an under-edited text file.

	
To this end I tentitatively suggest d-bus as a possible choice. It fills 1 and 2
nicely and also allows each module to have its own interfaces and objects. 
The IDL will also generate C bindings for both ends.

I should add I'm not a fan of d-bus, but it seems a better fit than JSON-RPC

James.