Welcome to the Companion Website for Understanding Unix/Linux Programming. This clear, readable text explains how Unix/Linux works and shows how to write programs that make full use of operating system services. The text explains all the major ideas of Unix programming:

• file I/O
• file systems
• device I/O
• the terminal driver
• timers
• signals
• processes
• pipes
• stream and datagram sockets
• network programming
• POSIX threads
• semaphores