Acknowledgments

We are very grateful to Mike Speciner and Bob Lynch for reading the entire manuscript and making many useful suggestions. We are especially grateful to Mary Lou Nohr for her careful and intelligent copy-editing. We would also like to express our appreciation to Neal Wagner and Radia Perlman for their encouragement and suggestions.

We have taught undergraduate and graduate operating systems courses from 1988 to date (2003), and much of the material in the book has been developed as part of teaching these courses. The students in these courses have suffered through drafts in various stages of development and have field- tested emerging projects. Their program bugs , comments, complaints, and suggestions made the book a lot better and gave us insight into how these topics interrelate. Some of the students who found errors in an early draft include Joseph Bell, Carlos Cadenas, Igor Grinshpan, Jason Jendrusch and James Manion. We would like to acknowledge the National Science Foundation for providing support through the NSFILI grant USE-0950497 to build a laboratory so that we had the opportunity to develop the original curriculum upon which this book is based. NSF (DUE-975093, DUE-9752165 and DUE-0088769) also supported development of tools for exploration and analysis of OS concepts.

We would like to thank Greg Doench, our editor at Prentice Hall, for guiding us through the process and William Mara our production editor, for bringing the book to publication. We typeset the book using LATEX2 , and we would like to express our appreciation to its producers for making this software freely available.

Special thanks go to our families for their unfailing love and support and especially to our children, Nicole and Thomas, who have dealt with this arduous project with enthusiasm and understanding.