Hangs up your phone. This disconnects all current links - the
    current conversation, anyone you have on hold, and anyone who has
    you on hold. The HANGUP command does not cause an exit from the
    Phone utility. (Compare this command with the EXIT command.)

    Pressing Ctrl/Z during a conversation is equivalent to
    entering the HANGUP command. (Pressing Ctrl/Z when there is no
    conversation is equivalent to entering the EXIT command.)

    Format

      HANGUP