Re: [RFC] keymap support for PVFB

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

On Fri, Jan 12, 2007 at 09:15:21AM +0100, Gerd Hoffmann wrote:
>   Hi,
> 
> >> I've tried to tackle the same issue by hacking the vnc client side to
> >> send us keysyms no matter what the local keyboard mapping is.  So I can
> >> have any keyboard map loaded on the host, qemu-dm/vncfb sees us keysyms
> >> nevertheless and passes the correct scancodes to the guest OS.
> > 
> > You mean scan codes, don't you?  Key symbols are the XK_a and so
> > forth.
> 
> No, keysyms.  This is what the vnc protocol uses, so there is no way
> around that, unfortunaly.  It takes the X11 keycodes and translates
> these to us keymap keysyms using a buildin table, then sends them.  So
> for the server side (from vnc protocol view, i.e. qemu-dm or vnc-fb) it
> looks like a vnc client with us keyboard.
> 
> > Passing scan codes in addition to key symbols makes sense.
> 
> Does the vnc protocol allow that?  I don't think so :-(

No, but there's no reason we couldn't come up with an extension. Anthony
has already done similar to allow passing of relative mouse co-ords instead
of absolute co-ords. Extensions are opt-in, so unless the client has support
they'd carry on with normal keysyms, but a client that understood the new
extension could switch to scan codes. The important thing is talking to
upstream VNC mailing lists about any proposed extension to get buy-in so
some of the popular clients implement it. As far as i'm concerned, I'm more
than happy to extend the virt-manager  VNC client if it could enable better
internationalized keyboard handling.

Dan.
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