[Qemu-devel] Re: [PATCH 28/50] error: Let converted handlers print in human monitor

[Luiz Capitulino <lcapitulino@redhat.com>]

On Thu, 04 Mar 2010 22:06:42 +0100
Markus Armbruster <armbru@redhat.com> wrote:

> Luiz Capitulino <lcapitulino@redhat.com> writes:
> 
> > On Thu,  4 Mar 2010 16:56:49 +0100
> > Markus Armbruster <armbru@redhat.com> wrote:
> >
> >> While fully converted handlers are not supposed to print anything when
> >> running in a QMP monitor, they are free to print in a human monitor.
> >
> >  I disagree.
> >
> >  One of the key decisions behind the new Monitor design is that handlers
> > are part of common code. User printing is output-specific and should not
> > be done by handlers.
> >
> >  One of the problems with this layer violation is that the consumer of this
> > data might not be what you have assumed. For example, it has been suggested
> > that we could move the qemu shell out of qemu in the future. In this case,
> > this kind of information _could_ be useful.
> 
> How do you intend to solve the problem of printing help then?

 Doesn't a shallow conversion takes care of it for now?

> The perfect is the enemy of the good.
> 
> >  Another important problem is that free printing like this is error-prone
> > as it's not at all clear what could be printed and there's no way to catch
> > mistakes mechanically. Not to mention that this is for sure going to used
> > by those who want to ignore QMP completely.
> 
> This paragraph I don't get.

 If something that should be available under qmp is printed by using
monitor_printf(), we loose big time.