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WdfRequestGetEffectiveIoType method

[Applies to UMDF only]

The WdfRequestGetEffectiveIoType method returns the buffer access method that UMDF is using for the data buffers of the specified I/O request.

Syntax


WDF_DEVICE_IO_TYPE WdfRequestGetEffectiveIoType(
  [in]  WDFREQUEST Request
);

Parameters

Request [in]

A handle to a framework request object.

Return value

WdfRequestGetEffectiveIoType returns a WDF_DEVICE_IO_TYPE-typed value that identifies the buffer access method that UMDF is using for the I/O request's data buffers.

Remarks

For more information, see Managing Buffer Access Methods in UMDF Drivers.

Examples

The following code example shows how an EvtIoWrite callback function can determine the buffer access method for the specified write request.


VOID
MyDrvEvtIoWrite(
  _In_  WDFQUEUE Queue,
  _In_  WDFREQUEST Request,
  _In_  size_t Length
)
{ 

...

    WDF_DEVICE_IO_TYPE iotype = WdfDeviceIoUndefined;
    
    iotype = WdfRequestGetEffectiveIoType(Request);

...

}


Requirements

Minimum support

Windows 8.1

Minimum UMDF version

2.0

Header

Wdfrequest.h (include Wdf.h)

Library

WUDFx02000.dll

IRQL

PASSIVE_LEVEL

See also

WDF_DEVICE_IO_TYPE

 

 

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