Re: [Qemu-devel] [PATCH 1/3] qmp/hmp: Add QMP getfd command that returns fd

[Luiz Capitulino <lcapitulino@redhat.com>]

On Wed, 06 Jun 2012 10:04:23 -0400
Corey Bryant <coreyb@linux.vnet.ibm.com> wrote:

> > Today, we return a dict on success:
> >
> >   { "return": {} }
> >
> > But this patch changes it to:
> >
> >   { "return": 42 }
> >
> > There are two ways to do this without breaking compatibility:
> >
> >   1. Add a new command (say get-file-descriptor)
> 
> What do you think about using getfd2 for the command name?  I'm thinking 
> getfd2 may be more obvious that it corresponds to closefd. 

We're going for more descriptive names in QMP. I don't have strong objections
against get-fd2 if there's consensus that 'fd' is better than 'file-descriptor',
although 'fd2' is a bit confusing.

> That assumes 
> we'll use the same array internally to store fds and closefd can be used 
> to close the fd opened by get-file-descriptor/getfd2.

You mean using the same array for getfd and get-file-descriptor? Yes, the
descriptor list is global.

> I assume this approach would still return an int:  { "return": 42 }

The new command? Yes.

> >   2. Return a type instead, like:
> >
> >       { "return": { "file-descriptor": 42 } }
> >
> > I think I prefer item 1, as we could also take the opportunity to fix the
> > argument type and improve its name. Besides, we don't have a schema to do 2.
> 
> Is it fdname that you think could be improved?  fdname seems pretty 
> straight forward to me.

What I'm trying to avoid is having too short names when that's not necessary.
I think I'd just use 'name' or 'file-descriptor-name' for the verbose option,
but I don't have strong objections against 'fdname'.