You can now take advantage of this library to provide full featured DirectX functionality to prototype your Open GL games. GL/OS offers very easy-to-use methods and interfaces to quickly take advantage of DirectInput, DirectSound, DirectMusic, and DirectPlay
Took a look at there API docs, and sample program.
This API wraps DirectInput, DirectSound, DirectMusic, and DirectPlay it what appears to be a simple to use set of objects.
Rendering is done on there callback Frame function, that you provide, and where you do all specific graphic rendering. There sample shows OpenGL code here, and check the state of the keyboard, mouse etc.