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Alerting the Processors

After the timer is set by ProcessReq, the DoBroadcast Triveni process becomes active and, in turn, sets another timer and broadcasts a command to all the processors to start collecting data. When the broadcast completes or this timer expires, the DoBroadcast Triveni process becomes inactive and the DoAllProcs Triveni process becomes active. This timer event is of lower priority than the TOTAL_TIMER_EXPIRED event. This is expressed through appropriate nesting of preemption operators: in particular, the Await construct for this timer event is nested inside the DoWatching construct for the TOTAL_TIMER_EXPIRED event.



1998-03-16