cannot open X apps from a root console window

flieslikeabeagl · 10-13-2004, 05:42 PM

Hi, I have Slackware 10.0 running on my AMD Duron 1300 box. While logged in as a normal user, I often open up a terminal window and use "su" to become root to run some administrative task. My problem is that I cannot open any GUI application while in this mode. As an example, when I try to run the Guarddog firewall app, I get errors like this:

Code:

Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified
guarddog: cannot connect to  X server :0.0

If I log directly into KDE as root, I have no such issues; but I know that running KDE as root is a Very Bad Thing (TM) to do.

Presumably this is due to the configuration of the X server in Slackware. Anyone know how to fix this issue?

TIA,
-Flieslikeabeagle

AltF4 · 10-13-2004, 06:16 PM

probably the $DISPLAY veriable is lost while "su"-ing

either set it manually ( "export DISPLAY=unix:0.0" ) or
use a version of su that supports the DISPLAY variable
(in SUSE i use the "/usr/X11R6/bin/sux" script)

-X- · 10-13-2004, 07:03 PM

You own the display and root isn't allowed to use it. Try;
$ xhost +
$ su
# <some X app>

"Much Better" way to to setup yourself to use sudo. Then;
$ sudo gvim /some/file

For sudo capabilities, as root do;
Add yourself to the wheel group. Then;
# visudo
uncomment this line.
%wheel ALL=(ALL) NOPASSWD: ALL

press <esc>
then <shift :>
then <wq>

Log out and back in.

Now you can sudo.

See... everyone should know vi/vim.

flieslikeabeagl · 10-13-2004, 08:47 PM

Thanks for the replies, folks. I'm at home now, but will try out your suggestions tomorrow when I'm back in front of the offending PC.

-X-, I downloaded and compiled from source the tarball for the Gnu Nano editor. Nano and FreeBSD's "ee" (easy editor) are the only two command line *nix editors I've run across that are compatible with my brain...my chances of remembering to "esc, shift, colon, w, q" every time I want to save a file are about as good as a snowballs in a lava flow. I actually had no choice other than to use vi for several years back in the early 90's, on Sun Sparkstations running Unix. When X and Solaris came along, a GUI text editor came with it. I have never been happier to stop using any piece of software than I was when I abandoned vi!

Don't get me wrong, I'm glad you enjoy vi. But its not for me - its for people who can mentally map extremely arbitrary key sequences to the simplest tasks a text editor might be asked to perform!

-Flieslikeabeagle

gbonvehi · 10-13-2004, 08:49 PM

You should try mcedit (the Midnight Commander editor) it's VERY easy to use. Just type: mcedit filename once you're in just edit as you like and hit ESC

If you need to do something like search or replaze look at the bottom that you've a list of commands that are executed with the F* keys ie: F2 = Save, F4 = Replace.
Oh and it comes installed with a default Slackware install

-X- · 10-14-2004, 04:42 AM

I understand, but there are times when you need to know vi/vim like visudo. Sure you can use nano else, but visudo is there for a purpose.

tobyl · 10-14-2004, 11:28 AM

I like pico, but then is that similar to nano?

Anyway my post is to draw flieslikeabeagl's attention to kdesu. It is X session aware, and helps me out sometimes. (It will start gtk apps as root too).

-X- · 10-14-2004, 02:05 PM

kdesu is a great GUI tool, but when you're at the command line sudo is really useful.

flieslikeabeagl · 10-15-2004, 02:13 PM

Thanks, guys! Both the "xhost+" trick and "kdesu" are working for me. Much appreciate the help. I just slapt-got (!) mc, and took a look at mcedit, it certainly seems as user friendly as you can get on the command line (does it use ncurses?).

tobyl, I believe nano is designed to be very close to pico .... something to do with pico not being GPL licensed, I believe.

-Flieslikeabeagle