This is the calendar reminder utility from the NetBSD distribution. It can be used in two different ways. When a non-root user runs calendar without any arguments, it examines the user`s calendar file, (the location is specified by the CALENDAR_DIR environment variable), and displays the user`s appointments for that particular day. When run by root with the -a option, calendar examines the calendar file in the login directory of each user on the system, and sends a reminder of any appointments to the user by mail. This will done for you every night by cron, (see /etc/cron.daily/calendar.cron). This binary may be redistributed, provided the Copyright notice is included in the distribution, (provided in the associated /usr/doc directory).