Re: [PATCH v2] char-pty: add support for the terminal size

["Daniel P. Berrangé" <berrange@redhat.com>]

On Wed, Sep 17, 2025 at 04:08:01PM +0200, Filip Hejsek wrote:
> 
> 
> On September 17, 2025 3:31:57 PM GMT+02:00, "Daniel P. Berrangé" <berrange@redhat.com> wrote:
> > [...]
> > > > 2. create a timer polling every eg 100ms to check if the winsize has
> > > > changed
> > [...]
> > 
> > I don't think we want a timer polling for an situation that will very
> > rarely arise.  We already add the 'chardev_resize' QMP command, which is
> > a good enough way to kick QEMU to re-read the size.
> 
> So the size provided in the command would be ignored, and QEMU would
> instead query the pty fd?

Actually I was just thinking we ignore the pty and only support the QMP
command. There is little point in trying for access size via the pty
if clients need the QMP command regardless to notify QEMU.

> Note that this would mean there is no size info if the command is
> not used, because the size will be 0x0 when the pty is created by
> QEMU (though we could add device parameters for the initial size).

We shouldn't send any size info to the guest if the hsot backend
does not have it available.

With regards,
Daniel
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