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KSEVENTDATA structure (ks.h)

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Kernel streaming clients send the KSEVENTDATA structure to the class driver to specify a notification method.

Syntax

typedef struct {
  ULONG NotificationType;
  union {
    struct {
      HANDLE    Event;
      ULONG_PTR Reserved[2];
    } EventHandle;
    struct {
      HANDLE Semaphore;
      ULONG  Reserved;
      LONG   Adjustment;
    } SemaphoreHandle;
    struct {
      PVOID     Event;
      KPRIORITY Increment;
      ULONG_PTR Reserved;
    } EventObject;
    struct {
      PVOID     Semaphore;
      KPRIORITY Increment;
      LONG      Adjustment;
    } SemaphoreObject;
    struct {
      PKDPC     Dpc;
      ULONG     ReferenceCount;
      ULONG_PTR Reserved;
    } Dpc;
    struct {
      PWORK_QUEUE_ITEM WorkQueueItem;
      WORK_QUEUE_TYPE  WorkQueueType;
      ULONG_PTR        Reserved;
    } WorkItem;
    struct {
      PWORK_QUEUE_ITEM WorkQueueItem;
      PKSWORKER        KsWorkerObject;
      ULONG_PTR        Reserved;
    } KsWorkItem;
    struct {
      PVOID    Unused;
      LONG_PTR Alignment[2];
    } Alignment;
  };
} KSEVENTDATA, *PKSEVENTDATA;

Members

NotificationType

Contains flags indicating what type of notification should be performed. The following table lists all the possible values for the NotificationType member.

NotificationType Flag Description
KSEVENTF_EVENT_HANDLE Indicates that a Win32 synchronization or notification object handle is being passed. The KSEVENTDATA.EventHandle.Event element contains the handle.
KSEVENTF_SEMAPHORE_HANDLE Indicates that a Win32 semaphore handle is being passed. The KSEVENTDATA.SemaphoreHandle.Semaphore element contains the handle.
KSEVENTF_EVENT_OBJECT Indicates that a pointer to a kernel synchronization or notification object is being passed. The KSEVENTDATA.EventObject.Event element contains a pointer to this object. This is available only to kernel-mode clients.
KSEVENTF_SEMAPHORE_OBJECT Indicates that a pointer to a kernel semaphore object is being passed. The KSEVENTDATA.SemaphoreObject.Semaphore element contains a pointer to this object. This is available only to kernel-mode clients.
KSEVENTF_DPC Indicates that a pointer to a kernel DPC structure is being passed. The KSEVENTDATA.Dpc.Dpc element contains a pointer to the DPC. This is available only to kernel-mode clients.
KSEVENTF_WORKITEM Indicates that a pointer to a kernel work item structure is being passed. The KSEVENTDATA.WorkItem.WorkQueueItem contains a pointer to the work item. This is available only to kernel-mode clients.
KSEVENTF_KSWORKITEM Indicates that a pointer to a kernel streaming work item structure is being passed. The KSEVENTDATA.KsWorkItem.WorkQueueItem contains a pointer to the work item, and is queued to a previously registered kernel streaming work item. This is available only to kernel-mode clients.

EventHandle

Defines the EventHandle structure.

EventHandle.Event

Contains a handle to a synchronization event when the KSEVENT_EVENT_HANDLE flag is set.

EventHandle.Reserved[2]

Reserved and set to zero.

SemaphoreHandle

Defines the SemaphoreHandle structure.

SemaphoreHandle.Semaphore

Contains a handle to a semaphore when the KSEVENT_SEMAPHORE_HANDLE flag is set.

SemaphoreHandle.Reserved

Reserved and set to zero.

SemaphoreHandle.Adjustment

Contains the adjustment to the semaphore when it is released.

EventObject

Defines the EventObject structure.

EventObject.Event

Defines the PVOID member Event.

EventObject.Increment

Defines the KPRIORITY member Increment.

EventObject.Reserved

Reserved and set to zero.

SemaphoreObject

Defines the SemaphoreObject structure.

SemaphoreObject.Semaphore

Defines the PVOID member Semaphore.

SemaphoreObject.Increment

Defines the KPRIORITY member Increment.

SemaphoreObject.Adjustment

Defines the LONG member Adjustment.

Dpc

Defines the Dpc structure.

Dpc.Dpc

Defines the PKDPC member Dpc.

Dpc.ReferenceCount

Defines the ULONG member ReferenceCount.

Dpc.Reserved

Reserved and set to zero.

WorkItem

Defines the WorkItem structure.

WorkItem.WorkQueueItem

Defines the PWORK_QUEUE_ITEM member WorkQueueItem.

WorkItem.WorkQueueType

Defines the WORK_QUEUE_TYPE member WorkQueueType.

WorkItem.Reserved

Reserved and set to zero.

KsWorkItem

Defines the KsWorkItem structure.

KsWorkItem.WorkQueueItem

Defines the PWORK_QUEUE_ITEM member WorkQueueItem.

KsWorkItem.KsWorkerObject

Defines the PKSWORKER member KsWorkerObject.

KsWorkItem.Reserved

Reserved for future use.

Alignment

Defines the Alignment structure.

Alignment.Unused

Not used.

Alignment.Alignment[2]

Reserved for internal use by AVStream. Minidrivers should not manipulate this member.

Remarks

For more information, see KS Events.

Requirements

Requirement Value
Header ks.h (include Ks.h)

See also

KDPC

KSEVENT

KsIncrementCountedWorker

KsRegisterWorker

WORK_QUEUE_ITEM

WORK_QUEUE_TYPE