Re: after 'su -', 'Can't open display'

[Martin Fluch <mfluch@mathphys.fsk.uni-heidelberg.de>]

Hi,

By default the Xserver doesn't listen to the tcp port (for security
reasons) and I'll guess thats the reason for your problem. I've added the
following few lines to the /root/.bashrc file:

   if [ ! "$LOGNAME" = "root" ] ; then
        export XAUTHORITY=/home/$LOGNAME/.Xauthority
   fi

This works for me.

Martin



On Wed, 21 Feb 2001, James Sinnamon wrote:

> Dear Debian user's,
> 
> My apologies for a question that should have been answered over and over
> again on this
> list (I have searced but not been able to find an answer),  or if I am
> on the wrong  list.
> 
> When I start X Windows, using the KDE window manager, I change to root
> (with su - )
> for administrative tasks.  However I seem unable to run X window
> applications.
> 
> Whatever X application  I try to run, I inevitably get a message similar
> to "... unable to open display".
> 
> Previously on other distributions of Linux, I have used, as root :
> 
>     export DISPLAY=localhost:0.0
> 
> and, prior to that,  as the normal user that started the X window
> session:
> 
>     xhost localhost
> 
> This somehow doesn;t work on Debian Linux (unstable distribution).
> 
> Would anybody be able to tell me why, and how to go about diagnosing the
> problem,
> or better still, what to do about it.
> 
> TIA,
> 
> James
> 
> --
> James Sinnamon  sinnamon@usq.edu.au
> 
> ph +61 7 46311490, +61 412 319669
> PO Box 517 Darling Heights QLD 4350
> 
> 
> 
> 
>