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Re: [LUG] X and export DISPLAY

 

Thomas Arrow wrote:
>
> What can I do? I'v tried (out of chroot) echo $DISPLAY and I get
> 
> :0.0

I think it is simply looking for the display ":0.0" in the chroot
environment, and it doesn't find it, because the sockets the X server is
listening on are in the real servers file system not the chroot.
Although I'm not sure precisely where they live these days.

Sockets, whilst they can be on the network, if local will exist
somewhere in the file system, gdm for example opens its socket in /tmp
(for better or worse) by default. Maybe X is in /tmp/.X11-unix, but it
is a long time since I looked at the innards of X, and I didn't
understand much of it then.

If you have networking or some other fancy working in the chroot, then
you may be able to "DISPLAY=hostname:0.0" (You'll need "xhosts" and
check that X is listen on tcp - it doesn't by default for security
reasons on most distros, usually "ps -ef | grep X" will show if it is
listening, otherwise "netstat" is your friend -- alternative "ssh -X"
from the real machine ;-).

Alternatively you may be able to start an X server in the chrooted
system first, "chroot /whatever; startX", and have displays on ctrl-alt
F7 and F8 maybe.

It is possible to do sneaky things with "mount", "ln" and such to make X
work cleverly here, but you'd need to understand more than I do about
what is going on, or Google harder.

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