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P R E F A C E
it is the difference between a reference manual and a work that is intended
to educate and inform.
My only regret about this book is that I would have liked for there to be
more information about other file systems and much more extensive perfor-
mance analyses of a wider variety of file systems. However, just like software,
a book has to ship, and it can't stay in development forever.
You do not need to be a file system engineer, a kernel architect, or have
a PhD to understand this book. A basic knowledge of the C programming
language is assumed but little else. Wherever possible I try to start from
first principles to explain the topics involved and build on that knowledge
throughout the chapters. You also do not need to be a BeOS developer or
even use the BeOS to understand this book. Although familiarity with the
BeOS may help, it is not a requirement.
It is my hope that if you would like to improve your knowledge of file sys-
tems, learn about how the Be File System works, or implement a file system,
you will find this book useful.
Acknowledgments
I'd like to thank everyone that lent a hand during the development of BFS and
during the writing of this book. Above all, the BeOS QA team (led by Baron
Arnold) is responsible for BFS being where it is today. Thanks, guys! The
rest of the folks who helped me out are almost too numerous to mention: my
fianc ´ee, Maria, for helping me through many long weekends of writing; Mani
Varadarajan, for taking the first crack at making BFS write data to double-
indirect blocks; Cyril Meurillon, for being stoic throughout the whole project,
as well as for keeping the fsil layer remarkably bug-free; Hiroshi Lockheimer,
for keeping me entertained; Mike Mackovitch, for letting me run tests on
SGI's machines; the whole BeOS team, for putting up with all those buggy
versions of the file system before the first release; Mark Stone, for approach-
ing me about writing this book; the people who make the cool music that gets
me through the 24-, 48-, and 72-hour programming sessions; and of course Be,
Inc., for taking the chance on such a risky project. Thanks!
Practical File System Design:The Be File System
, Dominic Giampaolo
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