Howto random background images in GDM3 - debian 6

Configure GDM3 to display random images from directory upon login screen.

A way to random background images in GDM3 - Debian 6. Should be applicable to other distributions, the only difference being configuration file paths. If you know of a simpler approach please let us know. PRECAUTION: I'm just a newbie customizing a family laptop, this may not work, or slow down or expose your system in ways i do not understand. Follow procedure at your own risk. 1- Creating PostLogin bash script. #as root cp /etc/gdm3/PostLogin/Default.sample /etc/gdm3/PostLogin/Default 2- Editing PostLogin bash script, this will take a random image from directory and make it the background image #as root Add the following to /etc/gdm3/PostLogin/Default and adjust the path to point your images directory.     #change background image dir='/your/image/directory' file=`/bin/ls -1 "$dir" | sort --random-sort | head -1` path=`readlink -f "$dir/$file"` # Converts to full path cp $path /wherever/you/want/background.jpg 3- Create the background image and change permissions for all users to change background image when logging out. touch /wherever/you/want/background.jpg chmod 777 /wherever/you/want/background.jpg #do not know if this is necessary 4- Editing GDM3 configuration file #as root edit /etc/gdm3/greeter.gconf-defaults Uncomment the following line and change background image path /desktop/gnome/background/picture_filename      /wherever/you/want/background.jpg Optionally uncomment: /desktop/gnome/background/picture_options       zoom And adjust config file to your likings. 5- Restarting GDM3 invoke-rc.d gdm3 reload /etc/init.d/gdm3 restart