How to start restricted graphical applications

If you want to open some restricted graphical application with your username, you can get the following error:

vbox@core:~$ su - root -c gparted
Password: 
(gpartedbin:27091): Gtk-WARNING **: cannot open display:

Well, there is a better and efficient way, via

gksudo

or

gksu

. They are doing practically the same thing, only the authentication is different. For

gksudo

you need to be in sudoers list and you input your user's password and for

gksu

you need the root password. Below you have an example with

gksu

:

vbox@core:~$ gksu gparted
======================
libparted : 1.8.8
======================

At this point, you will be prompted to input the root password:

That's pretty much it!