Expand Minimize

WdfRequestGetInformation method

[Applies to KMDF and UMDF]

The WdfRequestGetInformation method returns completion status information for a specified I/O request.

Syntax


ULONG_PTR WdfRequestGetInformation(
  [in]  WDFREQUEST Request
);

Parameters

Request [in]

A handle to a framework request object.

Return value

WdfRequestGetInformation returns the information that a lower-level driver set by calling WdfRequestSetInformation or WdfRequestCompleteWithInformation.

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

Remarks

A driver can call WdfRequestSetInformation or WdfRequestCompleteWithInformation to set completion status information for an I/O request. Your driver can call WdfRequestGetInformation after a lower-level driver completes a request, to obtain completion status information that the lower-level driver set.

If your driver calls WdfRequestGetInformation after it calls WdfRequestComplete to complete the request, WdfRequestGetInformation returns NULL.

For more information about WdfRequestGetInformation, see Completing I/O Requests.

Examples

The following code example sends an I/O request to an I/O target and then obtains status information that the I/O target provided.


ULONG_PTR  informationRetrieved = NULL;

status = WdfIoTargetSendWriteSynchronously(
                                           ioTarget,
                                           request,
                                           &outputMemoryDescriptor,
                                           NULL,
                                           NULL,
                                           &bytesWritten
                                           );
if (NT_SUCCESS(status)) {
    informationRetrieved = WdfRequestGetInformation(request);
}

Requirements

Minimum KMDF version

1.0

Minimum UMDF version

2.0

Header

Wdfrequest.h (include Wdf.h)

Library

Wdf01000.sys (KMDF);
WUDFx02000.dll (UMDF)

IRQL

<=DISPATCH_LEVEL

DDI compliance rules

DriverCreate, InvalidReqAccess, InvalidReqAccessLocal, KmdfIrql, KmdfIrql2

See also

WdfRequestCompleteWithInformation
WdfRequestSetInformation

 

 

Send comments about this topic to Microsoft

Show:
© 2014 Microsoft