xlock locks the X server until the user enters their password at the keyboard. While xlock is running, all new server connections are refused. The screen saver is disabled. The mouse cursor is turned off. The screen is blanked and a changing pattern is put on the screen. If a key or a mouse button is pressed then the user is prompted for the password of the user who started xlock. If the correct password is typed, then the screen is unlocked and the X server is restored. When typing the password, Control-U and Control-H are active as kill and erase respectively. To return to the locked screen, click in the small icon version of the changing pattern.