This book offers a unique and carefully integrated combination of principles and practice. While the usual principles are covered in detail, the book also describes a small, but real UNIX-like operating system: MINIX. It shows how it works and illustrates the principles behind it. By using MINIX, students learn principles and then can apply them in hands-on system design projects.* NEW - The principles material has been updated to reflect new developments in the field. * NEW - The MINIX system has been updated to run on 386, 486, and standard Pentium-based machines, and is based on the international POSIX standard. * NEW - Simulators for running MINIX on other systems are now available. * NEW - A CD-ROM included in each book contains all the MINIX source codes and a full-listing, as well as the simulators. * NEW - MINIX has been extended to include networking based in TCP/IP. The full source code of the MINIX TCP/IP implementation is included on the CD-ROM. * Still the only operating systems textbook that first explains the relevant principles, then shows how they apply to real systems by using a Unix-like operating system as a detailed example. * Relevant sections of MINIX code ar