Events are variable types mainly used for interprocess (thread) synchronization operations. Events can be passed as arguments to task and function calls to specify synchronization and trigger points.

Event variables have 3 valid values, OFF, ON, and null.

Syntax event variable_name [=initial_value];

Must be a valid identifier. initial_value

The only valid initial_value is null. If this specification is omitted, the initial value of the declared variable is OFF. If an event variable used in a trigger() system task has a null value, the trigger becomes always on

  1 program event_t {
  2   event try_event;
  3   event get_event;
  4   // Start the wait_event as parallel thread
  5   fork {
  6     wait_event();
  7   } join none
  8   // Wait till task wait_event has started execution
  9   sync(ALL, get_event);
 10   printf("Triggering event try_event\n");
 11   trigger(try_event);
 12   // Wait till task wait_event has done execution
 13   sync(ALL, get_event);
 14 }
 15 
 16 // Task which triggers/waits for events
 17 task wait_event() {
 18   // Inform that wait_event has started
 19   trigger(get_event);
 20   printf("Waiting for event try_event\n");
 21   sync(ALL, try_event);
 22   printf("Got event try_event\n");
 23   // Inform that wait_event has done with execution
 24   trigger(get_event);
 25 }

 Waiting for event try_event
 Triggering event try_event
 Got event try_event

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