Command:   leave - warn when it is time to go home
Syntax:    leave [ [+] hh[:]mm]
Flags:     (none)
Examples:  leave 1500               # Issue a warning at 2:55 p.m.
           leave 10:00              # Issue a warning at 9:55 a.m.
           leave + 30               # Issue a warning in 25 minutes

     Leave sets an alarm clock to a specified time and issues a  warning
5  minutes  before,  1 minute before, and at the time to leave.  It then
keeps issuing warnings every minute for 10 minutes, then quits.   If  no
time is provided, the program prompts for one.