WDF_REQUEST_TYPE enumeration (wudfddi_types.h)
[Warning: UMDF 2 is the latest version of UMDF and supersedes UMDF 1. All new UMDF drivers should be written using UMDF 2. No new features are being added to UMDF 1 and there is limited support for UMDF 1 on newer versions of Windows 10. Universal Windows drivers must use UMDF 2. For more info, see Getting Started with UMDF.]
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,
WdfRequestCreate,
WdfRequestCleanup,
WdfRequestRead,
WdfRequestWrite,
WdfRequestDeviceIoControl,
WdfRequestClose,
WdfRequestUsb,
WdfRequestOther,
WdfRequestInternalIoctl,
WdfRequestTypeNoFormat,
WdfRequestFlushBuffers,
WdfRequestQueryInformation,
WdfRequestSetInformation,
WdfRequestMaximum
} WDF_REQUEST_TYPE, *PWDF_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
Requirement | Value |
---|---|
Header | wudfddi_types.h (include Wudfddi.h) |
See also
IFileCallbackCleanup::OnCleanupFile
IFileCallbackClose::OnCloseFile
IQueueCallbackCreate::OnCreateFile