WdfRequestAllocateTimer function (wdfrequest.h)

[Applies to KMDF and UMDF]

The WdfRequestAllocateTimer method allocates a timer for a specified I/O request.

Syntax

NTSTATUS WdfRequestAllocateTimer(
 [in] WDFREQUEST Request
);

Parameters

[in] Request

A handle to a framework request object.

Return value

WdfRequestAllocateTimer returns STATUS_SUCCESS if the operation succeeds. Otherwise, this method might return one of the following values:

This method also might return other NTSTATUS values.

A bug check occurs if the driver supplies an invalid object handle.

Remarks

If your driver specifies a time-out value when calling WdfRequestSend, it should call WdfRequestAllocateTimer before calling WdfRequestSend. This ensures that the call to WdfRequestSend will not fail if there are insufficient system resources to allocate a timer.

If a timer is already allocated for the specified request, WdfRequestAllocateTimer returns STATUS_SUCCESS.

Examples

The following code example initializes a WDF_REQUEST_SEND_OPTIONS structure, allocates a timer object for the I/O request, and then calls WdfRequestSend.

NTSTATUS status;
WDF_REQUEST_SEND_OPTIONS options;
BOOLEAN requestSend;

WDF_REQUEST_SEND_OPTIONS_INIT(
 &options,
 WDF_REQUEST_SEND_OPTION_TIMEOUT
 );

WDF_REQUEST_SEND_OPTIONS_SET_TIMEOUT(
 &options,
 WDF_ABS_TIMEOUT_IN_SEC(TIME_OUT_VALUE)
 );
status = WdfRequestAllocateTimer(
 request
 );
if (!NT_SUCCESS(status)){
 return status;
...
 requestSend = WdfRequestSend(
 request,
 ioTarget,
 &options
 );
}

Requirements

See also

WDF_ABS_TIMEOUT_IN_SEC

WDF_REQUEST_SEND_OPTIONS_INIT

WdfRequestSend