I most certainly have the source to a pong clone [for OpenGL and GLUT] that will compile on OSX, Linux, FreeBSD, and Windows out of the box. Not even an ifdef.
What controls are used for the second paddle in this Pong clone? If a gamepad, then since when does GLUT support gamepads? If another computer, then since when does the same networking code work without modification (not even WSAStartup()) on Windows?