This is activated whenever the real-time clock is equal to the time specification you gave it. The time specifications should be one of two forms: HH:MM[AM|PM] where 1<=HH<=12 and 0<=MM<=59 HH:MM where 0<=HH<=23 and 0<=MM<=59 which form you use depends on the current setting of CLOCK_24HOUR. Time specification may include wildcards as well. The matching of the real-time clock and the time specification is a pure textual match. Of course, wildcards may be used in the time specification. The parameters for the action are as follows: $0 The time (format depends on CLOCK_24HOUR variable)
See Also: set/clock_24hour