WDF_REQUEST_TYPE (UMDF) enumeration

[Applies to UMDF 1.x only]

The WDF_REQUEST_TYPE enumeration identifies the types of I/O requests that a UMDF request object can represent.

Syntax


typedef enum _WDF_REQUEST_TYPE { 
  WdfRequestUndefined          = 0,
  WdfRequestCreate             = 1,
  WdfRequestCleanup            = 2,
  WdfRequestRead               = 3,
  WdfRequestWrite              = 4,
  WdfRequestDeviceIoControl    = 5,
  WdfRequestClose              = 6,
  WdfRequestUsb                = 7,
  WdfRequestOther              = 8,
  WdfRequestInternalIoctl      = 9,
  WdfRequestTypeNoFormat       = 10,
  WdfRequestFlushBuffers       = 11,
  WdfRequestQueryInformation   = 12,
  WdfRequestSetInformation     = 13,
  WdfRequestMaximum
} WDF_REQUEST_TYPE;

Constants

WdfRequestUndefined

The type of the request object is undefined.

WdfRequestCreate

The request object represents a file creation request. The driver receives this type of request object when an application opens a device by calling the Microsoft Win32 CreateFile function. The framework delivers this type of request, along with a newly created file object (IWDFFile), to the driver's IQueueCallbackCreate::OnCreateFile callback function. The new file object represents the HANDLE-typed file handle that the Win32 CreateFile returns.

WdfRequestCleanup

The request object represents a file cleanup request. The driver receives this type of request object after an application's call to the Win32 CloseHandle function closes the last handle to a file object, but possibly before all of the file's outstanding I/O requests have been completed or canceled. The framework delivers this type of request to the driver's IFileCallbackCleanup::OnCleanupFile callback function. (Also see WdfRequestClose.)

WdfRequestRead

The request object represents a read request. This driver receives this type of I/O request when an application calls the Win32 ReadFile or ReadFileEx function. The framework delivers this type of request to the driver's IQueueCallbackRead::OnRead callback function.

WdfRequestWrite

The request object represents a write request. This driver receives this type of I/O request when an application calls the Win32 WriteFile or WriteFileEx function. The framework delivers this type of request to the driver's IQueueCallbackWrite::OnWrite callback function.

WdfRequestDeviceIoControl

The request object represents a device I/O control request. This driver receives this type of I/O request when an application calls the Win32 DeviceIoControl function. The framework delivers this type of request to the driver's IQueueCallbackDeviceIoControl::OnDeviceIoControl callback function.

WdfRequestClose

The request object represents a file close request. The driver receives this type of request object after an application's call to the Win32 CloseHandle function closes the last handle to a file object, and after all of the file's outstanding I/O requests have been completed or canceled. The framework delivers this type of request to the driver's IFileCallbackClose::OnCloseFile callback function. (Also see WdfRequestCleanup.)

WdfRequestUsb

The request object was sent to a USB port. The IWDFRequestCompletionParams::GetCompletedRequestType method can return this value.

WdfRequestOther

This value is reserved for internal use only.

WdfRequestInternalIoctl

This value is reserved for internal use only.

WdfRequestTypeNoFormat

The request object's type has not been specified.

WdfRequestFlushBuffers

The request object represents a request to flush cached buffers. The framework delivers this type of request to the driver's IQueueCallbackDefaultIoHandler::OnDefaultIoHandler callback function.

WdfRequestQueryInformation

The request object represents a request to obtain information about a file. The framework delivers this type of request to the driver's IQueueCallbackDefaultIoHandler::OnDefaultIoHandler callback function.

WdfRequestSetInformation

The request object represents a request to set information about a file. The framework delivers this type of request to the driver's IQueueCallbackDefaultIoHandler::OnDefaultIoHandler callback function.

WdfRequestMaximum

The maximum value for the enumeration is exceeded.

Remarks

The WDF_REQUEST_TYPE enumeration is used as an input parameter of IWDFDevice::ConfigureRequestDispatching and IWDFIoQueue::ConfigureRequestDispatching. It is also used for the return value of IWDFIoRequest::GetType and IWDFRequestCompletionParams::GetCompletedRequestType.

For the KMDF version of this enumeration, see WDF_REQUEST_TYPE.

Requirements

Header

Wudfddi.h (include Wudfddi.h)

See also

IFileCallbackCleanup::OnCleanupFile
IFileCallbackClose::OnCloseFile
IQueueCallbackCreate::OnCreateFile
IQueueCallbackDeviceIoControl::OnDeviceIoControl
IQueueCallbackRead::OnRead
IQueueCallbackWrite::OnWrite
IWDFFile

 

 

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