Is there an environment variable that is set for Unity?

My script needs to be able to detect if the Unity is being used on top of the Gnome DE. The only other way I can think of is basically seeing if the config file is there.

Solution 1:

Ubuntu 11.10

1. Ubuntu session (compiz/unity)

   DESKTOP_SESSION=ubuntu
   GDMSESSION=ubuntu
   XDG_CURRENT_DESKTOP=Unity
   

2. Ubuntu 2D session (metacity):

   DESKTOP_SESSION=ubuntu-2d
   GDMSESSION=ubuntu-2d
   XDG_CURRENT_DESKTOP=Unity
   

3. Gnome session (gnome-shell):

   DESKTOP_SESSION=gnome-shell
   GDMSESSION=gnome-shell
   XDG_CURRENT_DESKTOP=GNOME
   

4. Gnome Classic session (metacity):

   DESKTOP_SESSION=gnome-classic
   GDMSESSION=gnome-classic
   XDG_CURRENT_DESKTOP=GNOME
   

5. Gnome Classic no effects session (metacity):

   DESKTOP_SESSION=gnome-fallback
   GDMSESSION=gnome-fallback
   XDG_CURRENT_DESKTOP=GNOME
   

Ubuntu 11.04

1. Ubuntu session (compiz/unity):

   DESKTOP_SESSION=gnome
   GDMSESSION=gnome
   

2. Ubuntu Classic session (compiz):

   DESKTOP_SESSION=gnome-classic
   GDMSESSION=gnome-classic
   

3. Ubuntu Classic no effects session (metacity):

   DESKTOP_SESSION=gnome-2d
   GDMSESSION=gnome-2d