IWDFIoRequest3 interface (wudfddi.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.]

To obtain the IWDFIoRequest3 interface, drivers call IWDFIoRequest::QueryInterface.


The IWDFIoRequest3 interface inherits from IWDFIoRequest2. IWDFIoRequest3 also has these types of members:

  • Methods


The IWDFIoRequest3 interface has these methods.


The GetUserModeDriverInitiatedIo method determines whether an I/O request is marked as initiated by a UMDF driver.

The RetrieveActivityId method retrieves the current activity identifier associated with an I/O request.

The SetActivityId method associates an activity identifier with an I/O request.

The SetUserModeDriverInitiatedIo method indicates to kernel-mode drivers that sit below the UMDF driver in the same device stack that a particular request should be treated as though it came from a UMDF driver.


End of support Unavailable in UMDF 2.0 and later.
Target Platform Desktop
Minimum UMDF version 1.11
Header wudfddi.h

See also