If you are trying to open gedit from the terminal in centos you gor probably a  Gtk-WARNING Similar to this : [root@www ~]# sudo gedit No protocol specified (gedit:4368): Gtk-WARNING **: cannot open display: :0.0 To fix this issue : With ROOT [root@www]# export DISPLAY=:0.0 (Normal user) [kbilel@www ~]$ xhost +local:root non-network local connections being added … Lire la suite Gtk-WARNING **: cannot open display: :0.0 ( Solution )