trouble running program in terminal after using 'su -l username'

[David Jackson]

> (gnome-terminal:31609): Gtk-WARNING **: cannot open display:
>
> By default in Fedora X server is set to "-nolisten tcp". You can change
> that in /etc/X11/gdm/gdm.conf by setting DisallowTCP=true -> false.
> After X restart and trying what you want to achieve you have to also set
> "xhost +localhost". You can set that line for automatically be executed
> in /etc/X11/xinit/xinitrc.

Is that like doing a export DISPLAY=localhost:0.0
Could John use VNC?

> Alexander
>
> I hope you are running X as normal user and switch to root only by
> opening a terminal and calling "su -" in it. Easiest way to get an
> additional user console would be to open a new terminal. Never ever run
> X as root!
I so parnoid, I setup sudo for my user account :)

David