[LightDM] Greeter and other clients cannot connect to X server

[Guido Berhoerster]

* Robert Ancell <robert.ancell at gmail.com> [2013-11-26 04:51]:
> The first place to look should be the X authority file - perhaps it has got
> corrupt for some reason? If you could copy it from inside the scripts
> before and after they run it would be useful to analyse. The authority file
> is deleted once the X server stops.

I've had one of the users extract the xauthority file[*] before
starting the X server (by wrapping the xserver-command) and at
the beginning of the greeter-setup-script, based on a quick
examination with xauth the seem intact, yet tools in the same
greeter-setup-script cannot connect.

* https://bugzilla.novell.com/show_bug.cgi?id=846832#c11

> 
> Unfortunately xlib/xcb is not very good at reporting why it can't connect
> to the X server :(

I'm completely in the dark, any other ideas? Should I open a bug
on launchpad yet?
-- 
Guido Berhoerster