Re: [Qemu-devel] [PATCH v10 09/16] block: Add QMP support for streaming to an intermediate layer

[Alberto Garcia]

On Tue 11 Oct 2016 06:32:39 PM CEST, Markus Armbruster wrote:

>>> 3) QEMU could advertise that feature to the client. This is probably
>>> simpler than trying to figure it out from the API. I guess that's
>>> the idea of 'qmp_capabilities'?
>>
>> I think that was the idea, though it was never used. If we had used
>> it, I'm not sure how long the capabilities list would be today. :-)
>
> QMP capabilities are for changes in the QMP protocol, not for changes
> in commands, events and types.  The protocol has been good enough so
> far, thus no capabilities.

I see. Wouldn't it make sense in general to have a way to ask QEMU
whether some certain feature is supported?

Berto