Xlib is a library which provides functions for applications running under the X Window System (also referred to as X). This includes window management as well as event handling. X is a network orientated system: An application which is running on computer A can send its graphical output to computer B, which is located somewhere else in the network (the network can be a LAN as well as the internet), and can receive events like keyboard or mouse input from computer B. This requires that a program called the “X-Server” is running on both computers. In Linux, the X-server is started with the command startx. You will most probably not have to start the X-server manually, because most Linux Distributions will set up the system to automatically start X after booting.
In the following, a small program framework will be developed, which uses the GLX extension to the X windows system. Only little knowledge of X will be needed; for a comprehensive introduction to X the “Xlib Programming Manual” by Adrian Nye can be recommended.
The program starts with the inclusion of the header files:
Another tutorial about OpenGL Programming in Linux is here