Re: How to reconnect to a new X Server

[Dr. H. Nikolaus Schaller]

Am 22.05.2013 um 11:34 schrieb Sebastian Reitenbach:

> Hi,
> 
> working with Riccardo on GAPs loginpanel, made some progress, but ran into 
> trouble now.
> 
> What I do is starting the X Server, before I then start the loginpanel 
> application.
> Then the loginpanel actually has an X server running, where it can connect to.
> 
> So far, that works well. I can login. When I logout, then I am killing the X 
> server, and
> want to restart it, and spawn the loginpanel again.
> 
> First I tried in loginpanels main function:
> 
>   while (1)
>     {
>       [XManager startXServer];
>       putenv("DISPLAY=:0.0");
> 
>       NSApplicationMain(argc, argv);
> 
>     }
> 
> 
> That probably was too naive from me thinking it might work ;) Reading up 
> NSApplication
> documentation, I see that everything after NSApplicationMain(argc, argv); 
> will not be 
> exectuted, so the while loop will only runs once :(
> 
> Anyways, then I tried to start the XServer again, after I teared it down.
> That works so far, but when the loginpanel wants to reset its window on the X 
> server, 
> I see it crying on the console, that the connection to the XServer broke:
> 
> X connection to :0.0 broken (explicit kill or server shutdown)
> 
> Even if there is a new server spawned already on the same display.
> 
> Is there a way to tell the application that the X Server disappeared, and it
> should reconnect to the new one? Or tell it to kind of respawn itself?

I think what you are looking for should be done in the startx or xinit scripts 
of
your system. They are usually responsible for restarting X servers. Also
initd and its run-levels play some role.

So the loginpanel should also be restarted by the same mechanism.
I.e. you could try to make it sort of a display and/or window manager.

Nikolaus