Event System Overview The event system consists of several components. Table 14 Event System Components Component Description Event Object Represents program interest in a set of events, and the occurrence of a matching event. See Events. Event Driver The event driver recognizes the occurrence of events, and places them in the appropriate event queues for dispatch. Rendezvous software starts the event driver as part of its process initialization sequence (the open call). See Event Driver. Event Queue A program creates event queues to hold event objects in order until the program can process them. See Event Queues. Event Queue Group Programs can organize event queues into groups for fine-grained control of dispatch priority. See Queue Groups and Priority. Event Dispatch Call A Rendezvous function call that removes an event from an event queue or queue group, and runs the appropriate callback function to process the event. See Dispatch. Callback Function A program defines callback functions to process events asynchronously. See Callback Functions. Dispatcher Thread Programs usually dedicate one or more threads to the task of dispatching events. Callback functions run in these threads.
