PCPFNEVENT_HANDLER callback function (portcls.h)
An EventHandler routine processes event requests.
Syntax
PCPFNEVENT_HANDLER PcpfneventHandler;
NTSTATUS PcpfneventHandler(
[in] PPCEVENT_REQUEST EventRequest
)
{...}
Parameters
[in] EventRequest
Pointer to an initialized PCEVENT_REQUEST structure
Return value
The event handler returns STATUS_SUCCESS if the call was successful. Otherwise, it returns an appropriate error code.
Remarks
Each event that a miniport driver exposes is associated with an event handler. The purpose of the event handler is to process event requests from the port driver and its clients. EventRequest is an input parameter to the handler that contains the following information about the event:
- The event set GUID and event ID.
- How the event is to be triggered.
- Pointers to the target miniport object and (for a pin) stream object.
The miniport driver exposes its event handlers through its IMiniport::GetDescription method. This method outputs a descriptor structure (see PCFILTER_DESCRIPTOR) that defines the filter that the miniport driver and its associated port driver implement together. This structure contains a pointer to the miniport driver's automation table (see PCAUTOMATION_TABLE), which in turn contains a pointer to an array of the miniport driver's events. Each array element is a PCEVENT_ITEM structure and contains a PCPFNEVENT_HANDLER function pointer to the handler for the event.
The EventHandler routine must reside in nonpaged memory.
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Desktop |
| Header | portcls.h (include Portcls.h) |
See also
IPortEvents::AddEventToEventList