[Qemu-devel] Re: [PATCH 01/11] QMP: Introduce specification file

[Avi Kivity]

On 06/23/2009 04:06 PM, Luiz Capitulino wrote:
> > I don't see you update that file anywhere.  In any case, my preference
> > would be to have everything in one file.
> >      
>
>   Sorry, I forgot to mention that I wouldn't include this file
> in the patchset.
>    

You mean now, or forever?

>   Ok, as Daniel also said we will need this.
>
>   The only problem is that I was trying to avoid changing commands'
> output too much, because this can turn into a maintenance nightmare.
>
>   Note that we will have to maintain two protocols: the current existing
> (user mode) and this new control mode.
>    

I don't see a way out.  The current protocol is not machine consumable, 
but we can't change it.  We'll just have to live with it.

> > Clients should never make decisions based on the qemu or qmp version.
> > Rather, we should provide a facility to query the availability of features.
> >      
>
>   Right. What about changing 'help' output to only list command names?
>    

Also command subfeatures, when new subfeatures are added.

> > Maybe add a numeric error code (to be defined by individual commands).
> >      
>
>   Well, numeric error codes seem redundant in text protocols. At least,
> POP3 and IMAP don't use them.
>
>   This may seem contradictory, but although this a low-level protocol,
> I feel that text protocols tend to be very descriptive.
>    

Well, the strings are not single words, so the key for the application 
is "all words until the end of the line".  Not too machine friendly.

--
error compiling committee.c: too many arguments to function