KSEVENT_ITEM structure (ks.h)

The KSEVENT_ITEM structure describe a minidriver's support for a specific event within an event set.

Syntax

typedef struct {
  ULONG            EventId;
  ULONG            DataInput;
  ULONG            ExtraEntryData;
  PFNKSADDEVENT    AddHandler;
  PFNKSREMOVEEVENT RemoveHandler;
  PFNKSHANDLER     SupportHandler;
} KSEVENT_ITEM, *PKSEVENT_ITEM;

Members

EventId

Specifies the unique ID of the event within the event set.

DataInput

Specifies the size in bytes of event data. The event data begins with a KSEVENTDATA structure that describes how the client should be notified when the event occurs, optionally followed by any additional parameters that specify when the event occurs. Must be at least sizeof(KSEVENTDATA).

ExtraEntryData

Specifies the size in bytes of any additional memory that the system should allocate for each enable request for this event. The driver uses this memory to store any data it needs to keep track of the event request. The memory is allocated directly after the event enable request's KSEVENT_ENTRY structure.

AddHandler

Pointer to a minidriver-supplied AVStrMiniAddEvent callback routine. Not used by the stream class driver. For AVStream minidrivers only.

RemoveHandler

Pointer to a minidriver-supplied AVStrMiniRemoveEvent callback routine. Not used by the stream class driver. For AVStream minidrivers only.

SupportHandler

Not used by the stream class driver.

Remarks

A minidriver that specifies the AddHandler and RemoveHandler members and does not properly clean the events up can cause a resource (memory/handle) leak.

Requirements

See also

IOCTL_KS_DISABLE_EVENT

KSEVENTDATA

KSEVENT_ENTRY

KsDefaultAddEventHandler