1<html> 2<title> 3preface3 4</title> 5<body BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#330088" ALINK="#FF0044"> 6<H1>Preface to the Third (2000) Edition 7</H1> 8<br> <br> 9A great deal has happened to Plan 9 in the five years since its last release. 10Although much of the system will seem familiar, hardly any aspect 11of it is unchanged. 12The kernel has been heavily reworked; 13the graphical environment completely rewritten; 14many commands added, deleted, or replaced; 15and the libraries greatly expanded. 16Underneath, though, the same approach to computing remains: 17a distributed system that uses file-like naming to access and 18control resources both local and remote. 19<br> <br> 20Some of the changes are sweeping: 21<DL> 22<DT><DT> <DD> 23Alef is gone, a casualty of the cost of maintaining multiple languages, compilers, 24and libraries in a diverse world, 25but its model for processes, tasks, and communication lives on 26in a new thread library for C. 27<DT><DT> <DD> 28Support for color displays is much more general, building on a new 29alpha-blending graphical operator called 30<TT>draw</TT> 31that replaces the old 32<TT>bitblt</TT>. 33Plan 9 screens are now, discreetly, colorful. 34<DT><DT> <DD> 35A new mechanism called plumbing connects applications together 36in a variety of ways, most obviously in the support of multimedia. 37<DT><DT> <DD> 38The interfaces to the panoply of rotating storage devices have been 39unified and extended, 40while providing better support for having Plan 9 coexist with other 41operating systems on a single disk. 42<DT><DT> <DD> 43Perhaps most important, this release of the system is being done under 44an open source agreement, providing cost-free source-level access to the 45software. 46</dl> 47<br> <br> 48Plan 9 continues to be the work of many people. 49Besides those mentioned in the old preface, 50these people deserve particular note: 51Russ Cox did much of the work updating the graphics 52and creating the new disk and bootstrap model 53as well as providing a number of new commands; 54David Hogan ported Plan 9 to the Dec Alpha; 55and 56Sape Mullender wrote the new thread library. 57<br> <br> 58Other new contributors include 59Bruce Ellis, 60Charles Forsyth, 61Eric Van Hensbergen, 62and 63Tad Hunt. 64<br> <br> 65<DL><DT><DD> 66<DL><DT><DD> 67<DL><DT><DD> 68<DL><DT><DD> 69<DL><DT><DD> 70<DL><DT><DD> 71<DL><DT><DD> 72<DL><DT><DD> 73Bell Labs 74<br> 75Computing Science Research Center 76<br> 77Murray Hill NJ 78<br> 79June, 2000 80 81<br> <br> 82<A href=http://www.lucent.com/copyright.html> 83Copyright</A> © 2000 Lucent Technologies Inc. All rights reserved. 84</body></html> 85