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The KeInitializeEvent routine initializes an event object as a synchronization (single waiter) or notification type event and sets it to a signaled or not signaled state.
VOID
KeInitializeEvent(
IN PRKEVENT Event,
IN EVENT_TYPE Type,
IN BOOLEAN State
);
None
Declared in wdm.h and ntddk.h. Include wdm.h or ntddk.h.
A caller cannot wait at raised IRQL for a nonzero interval on an event object or in a nonarbitrary thread context.
Storage for an event object must be resident: in the device extension of a driver-created device object, in the controller extension of a driver-created controller object, or in nonpaged pool allocated by the caller. If you allocate the event on the stack, you must specify a KernelMode wait when calling KeWaitForSingleObject, KeWaitForMutexObject, or KeWaitForMultipleObjects. During a KernelMode wait, the stack containing the event will not be paged out
Drivers typically use a NotificationEvent to wait for an I/O operation to complete. When a notification event is set to the signaled state, all threads that were waiting on the event become eligible for execution. The event remains in the signaled state until a thread calls KeResetEvent or KeClearEvent to set the event in the not-signaled state.
A SynchronizationEvent is also called an autoreset or autoclearing event. When such an event is set, a single waiting thread becomes eligible for execution. The Kernel automatically resets the event to the not-signaled state each time a wait is satisfied. A driver might use a synchronization event to protect a shared resource that is used in synchronizing the operations of several threads. Synchronization events are rarely used in a typical driver.
Callers of this routine can be running at any IRQL.
KeClearEvent, KeReadStateEvent, KeResetEvent, KeSetEvent, KeWaitForMultipleObjects, KeWaitForSingleObject