ABSTRACT
Event flags provide a powerful tool for thread synchronization. Event flags can be set or cleared by any thread and can be inspected by any thread. Event flags that satisfy a get request are cleared if the request specifies either of the options TX_OR_CLEAR or TX_AND_CLEAR. An application can create event flags groups either during initialization or during runtime. The characteristics of each event flags group are found in its Control Block. It contains information such as the values of event flags, the reset search flag, the pointer to the suspension list for this event flags group, and the number of threads suspended for this group. There are three services that enable to retrieve vital information about event flags groups. The first such service for event flags groups retrieves a subset of information from the Event Flags Group Control Block. The other two services provide summary information that is based on the gathering of run-time performance data.
