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28 /*=============================================================================
29 VideoCore OS Abstraction Layer - public header file for events
30 =============================================================================*/
39 #include "interface/vcos/vcos_types.h"
45 * An event is akin to the Win32 auto-reset event.
48 * Signalling an event will wake up one waiting thread only. Once one
49 * thread has been woken the event atomically returns to the unsignalled
52 * If no threads are waiting on the event when it is signalled it remains
55 * This is almost, but not quite, completely unlike the "event flags"
56 * object based on Nucleus event groups and ThreadX event flags.
58 * In particular, it should be similar in speed to a semaphore, unlike
63 * Create an event instance.
65 * @param event Filled in with constructed event.
66 * @param name Name of the event (for debugging)
68 * @return VCOS_SUCCESS on success, or error code.
71 VCOS_STATUS_T vcos_event_create(VCOS_EVENT_T *event, const char *name);
73 #ifndef vcos_event_signal
76 * Signal the event. The event will return to being unsignalled
77 * after exactly one waiting thread has been woken up. If no
78 * threads are waiting it remains signalled.
80 * @param event The event to signal
83 void vcos_event_signal(VCOS_EVENT_T *event);
88 * @param event The event to wait for
89 * @return VCOS_SUCCESS on success, VCOS_EAGAIN if the wait was interrupted.
92 VCOS_STATUS_T vcos_event_wait(VCOS_EVENT_T *event);
95 * Try event, but don't block.
97 * @param event The event to try
98 * @return VCOS_SUCCESS on success, VCOS_EAGAIN if the event is not currently signalled
101 VCOS_STATUS_T vcos_event_try(VCOS_EVENT_T *event);
109 void vcos_event_delete(VCOS_EVENT_T *event);