WdfDeviceGetFileObject function (wdfdevice.h)

[Applies to KMDF only]

The WdfDeviceGetFileObject method returns a handle to the framework file object that is associated with a specified WDM file object.

Syntax

WDFFILEOBJECT WdfDeviceGetFileObject(
 [in] WDFDEVICE Device,
 [in] PFILE_OBJECT FileObject
);

Parameters

[in] Device

A handle to a framework device object.

[in] FileObject

A pointer to a WDM FILE_OBJECT structure.

Return value

WdfDeviceGetFileObject returns a handle to the framework file object that is associated with the specified WDM file object. If a framework file object was not created for the file, or if the FileObject pointer is invalid, the method returns NULL.

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

Remarks

For more information about framework file objects, see Framework File Objects.

Examples

The following code example obtains a pointer to a named WDM device object and its corresponding WDM file object, if the requested access to the objects can be granted. Then, the example obtains a handle to the framework file object that is associated with the WDM file object.

PFILE_OBJECT pWdmFileObject = NULL;
PDEVICE_OBJECT pWdmDeviceObject = NULL;
WDFFILEOBJECT fileObject = NULL;
NTSTATUS status = STATUS_SUCCESS;
BOOLEAN success = TRUE;

status = IoGetDeviceObjectPointer(
 &inputFileName, // File name 
 FILE_ALL_ACCESS, // Access mask
 &pWdmFileObject, // Output pointer of WDM file object
 &pWdmDeviceObject // Output pointer of WDM device object
 );

if(!NT_SUCCESS(status)){
 success = FALSE;
 break;
}

fileObject = WdfDeviceGetFileObject(
 gDeviceObject, // Handle to device object
 pWdmFileObject // Handle to WDM file object
 );
if(fileObject == NULL){
 success = FALSE;
}

Requirements

See also

IoGetDeviceObjectPointer