Events in Video Miniport Drivers (Windows 2000 Model)

The video port driver provides support for events, a type of kernel dispatcher object that can be used to synchronize two threads running below DISPATCH_LEVEL. A video miniport driver can use events to synchronize access to the video hardware:

  • By the video miniport driver and the display driver

  • By the display or video miniport driver and another component, such as an OpenGL driver or a program extension (such as the Display program in Control Panel).

The following table lists the event-related functions that the video port driver supplies.

Function Description


Sets a given event object to the nonsignaled state.


Creates an event object.


Deletes the specified event object.


Returns the current state of a given event object: signaled or nonsignaled.


Sets an event object to the signaled state if it was not already in that state, and returns the event object's previous state.


Puts the current thread into a wait state until the given dispatch object is set to the signaled state, or (optionally) until the wait times out.

GDI also provides support for events to display drivers. See Using Events in Display Drivers for more information.

For a broader perspective on events, see Event Objects in the Kernel-Mode Drivers Design Guide.

Send comments about this topic to Microsoft