Transfer display of active windows remotely

[Jim Gettys]

This transfer of display is already implemented in the GTK tookit,
though there are serious loose ends.  There is a teleport application to
signal a window to migrate.

The loose ends are:
	o last I looked, while the window got moved, the toolkit retained an
open connection to the original server.  This was due to Xlib
shortcomings, where to hack in support to handle errors properly would
have been a pain.  With Xcb now is the time to finish this up.
	o authentication is an issue.  You want to ensure that windows can't
easily be grabbed; but more importantly, you want casual use of displays
to be possible, so prior use of ssh is pretty heavyweight.  Ideally,
some work with a library like cyrus sasl might be useful to make
migration really practical.
                               - Jim


On Sat, 2008-10-11 at 03:27 -0700, Prasad H.L. wrote:
> This is what I have in mind.
> 
> - Consider display :0 on machine 1 (m1) and display :0 on machine 2 (m2).
> - Let us say, a process 'p1' running under privileges of user 'u' opens a window on :0 of m1.
> - I do an 'ssh -X u at m1' in xterm on :0 of m2 and login to m1.
> - Now, from that xterm window, is there any way by which I can make that window of process 'p1' appear on :0 of m2.
> 
> This kind of situation regularly occurs to me and some of my friends. We have multiple terminals at our disposal. On one terminal, I start some xterm which is, let us say, showing output of some process. I go to some other department in the institute and do an ssh to that terminal. Now, I have no way of seeing what is going on in that xterm. Well, this is a simple example, of course. 
> 
> Another example (though childish). Consider a case where I have a browser window with many tabs open in it, the window being displayed on :0 of m1. I would like to export it to :0 of m2 when I go and sit in front of m2. Before closing ssh on m2, I re-export the window back to :0 of m1 and then quit the ssh. Such a feature would be really great to have. Since, any way, currently the only dependency on the remote machine is that it should have an X server running, I believe this feature should be implementable if not already present.
> 
> With Regards,
> Prasad H. L.
> 
> --- On Sat, 10/11/08, Pat Kane <pekane52 at gmail.com> wrote:
> > Prasad,
> > 
> > Your question is very interesting, could you draw a picture
> > for me  of what you want to do?
> > 
> > Pat
> > ---
> > 
> > 
> > On Fri, Oct 10, 2008 at 11:50 PM, Prasad H.L.
> > <hlprasu at yahoo.com> wrote:
> > > I am active user of X.org and I admire the power and
> > features that X.org
> > > provides to the users. I regularly use exported
> > display over an ssh session and operate. I commend the
> > developers for such a wonder piece of software. However, I
> > would like to know one thing as described below.
> > >
> > > Consider a case where a window has been opened on the
> > local terminal with some user id. After performing a remote
> > login to and exporting the display to that machine using the
> > same user id, is there any way by which the display of that
> > opened window can be transferred to the remote exported
> > display and vice versa? If not possible, then please
> > consider this as a feature request.
> > >
> > > With Regards,
> > > Prasad H. L.
> > >
> > > ---
> > > Prasad H. L.
> > > PhD Student (with Dr. Shalabh Bhatnagar),
> > > Department of Computer Science and Automation,
> > > Indian Institute of Science,
> > > Bangalore - 560012
> > >
> > >
> > >
> > > _______________________________________________
> > > xorg mailing list
> > > xorg at lists.freedesktop.org
> > > http://lists.freedesktop.org/mailman/listinfo/xorg
> > >
> 
> 
>       
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-- 
Jim Gettys <jg at laptop.org>
One Laptop Per Child