Terminate Unresponsive Programs

Xkill is part of the X11 utilities pre-installed in Ubuntu and a tool for terminating misbehaving X clients or unresponsive programs. You can easily add a shortcut key to launch xkill with the steps below.

1. Go to System > Preferences > Keyboard Shortcuts.
2. Click the Add button to create a custom shortcut.
3. Enter xkill to both the Name and Command boxes and click the Apply button.
4. Click on Disabled at the xkill row in the Keyboard Shortcuts window (Disabledis then changed to New shortcut...).
5. Press a new key combination, e.g. Ctrl+Alt+X (New shortcut... is then changed to Ctrl+Alt+X).
6. Click the Close button.

Xkill is ready for use. Press the above key combination to turn the cursor to an X-sign, move the X-sign and drop it into a program interface to terminate the unresponsive program, or cancel the X-sign with a right-click.