Select a process entry in the Process Manager scrolling pane.
Choose Kill from the Process menu.
Process Manager kills the process (and its child processes) provided that you have permission to do so; otherwise an error is displayed. Sometimes it takes several seconds for the process to terminate. You can tell that a process has been killed if it is not listed the next time Process Manager updates its display.
The equivalent UNIX command is:
kill -9 PID where PID is the process ID of the selected process.
You can redefine the command performed by the Kill menu item to a different command by redefining the action labelled 'Kill' in the file: