Registering for Device Interface Change Notification

A driver registers for notification of device interface arrival and removal events by calling IoRegisterPlugPlayNotification.

The following information applies to calling this routine for device interface change notification:

• Specify an EventCategory of EventCategoryDeviceInterfaceChange.
• EventCategoryData must point to the GUID for a device interface class.

  The GUID for a interface class is typically defined in a header file with the structures, constants, and so forth, for the interface.

• Specify an EventCategoryFlags of PNPNOTIFY_DEVICE_INTERFACE_INCLUDE_EXISTING_INTERFACES.

  This flag directs the PnP Manager to register the CallbackRoutine for future device interface arrivals and departures of the specified class and to call the CallbackRoutine immediately for any relevant device interfaces that are already active.

  A driver can call IoGetDeviceInterfaces to get a list of existing interfaces of a specific class and then register its callback routine without this flag, but using the flag is easier and avoids a potential timing issue.

• Specify a driver-defined Context, if appropriate, that the PnP Manager will pass to the callback routine.

A driver that opens a handle to a device in response to a device interface arrival notification should register for EventCategoryTargetDeviceChange events on the device. (See Using PnP Target Device Change Notification.)

A driver cancels notification registration by calling IoUnregisterPlugPlayNotification with the NotificationEntry returned by IoRegisterPlugPlayNotification.