Re: [Qemu-devel] Multiple QMP socket clients

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Daniel P. Berrange (berrange@redhat.com) wrote:
> On Tue, Oct 11, 2016 at 12:26:37PM +0200, Samuel Ortiz wrote:
> > Hi,
> > 
> > On a qemu instance started with a qmp unix socket:
> > 
> > -qmp unix:/tmp/ctrl.sock,server,nowait
> > 
> > I am trying to have multiple clients working on that socket but
> > although the qmp server seems to accept the connections, only the first
> > connected client gets his request processed. The next client requests
> > will just hang until the first one exits.
> > 
> > Is that an intended behaviour ?
> 
> Yes, the character device code is designed around the idea of a single
> endpoint.
> 
> In the case of the monitor you could work around it by adding multiple
> -qmp arguemnts, each with different socket. Of course you have to make
> sure each client doesn't trample on the other client when doing this.

But why does it accept the connection?
I thought you could say only accept a single connection on a socket.
(The backlog parameter to listen(2) but I can't find out listen.)

Dave

> 
> 
> Regards,
> Daniel
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--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK