To set the alarm, choose Properties -> Clock menu.
Use the Alarm Hr and Min settings to specify the time for an alarm. Use the Alarm command text field to type in the command that you'd like to take place at the alarm time. If you don't specify a command, the Clock application will beep. For example, if your workstation has audio capabilities you can set the Clock to create a cuckoo sound with the following Alarm command:
sh -c "cat /usr/demo/SOUND/sounds/cuckoo.au > /dev/audio''
Use the Repeat settings to specify whether the alarm should happen just one time, or every day at the given time. The alarm will not occur if the Repeat setting is none.
If you want a command to take place hourly, type that command in the Hourly command text field. Clock processes this command as hourly and alarm commands, for example, $HOME/clock.hourly.