xref: /plan9/sys/doc/release3.ms (revision 426d2b71458df9b491ba6c167f699b3f1f7b0428)
1.HTML "Plan 9 — Third Edition Release Notes
2.TL
3Plan 9 From Bell Labs
4.br
5Third Release Notes
6.br
7June 7, 2000
8.LP
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10.nf
11.ce 1000
12Copyright © 2000 Lucent Technologies Inc.
13All Rights Reserved
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15.fi
16.LP
17The third release of the Plan 9 operating system from Bell Labs
18is something of a snapshot of the current system.
19This differs from the previous, 1995 release,
20which was a more coordinated, well-defined release of an already-out-of-date
21system.
22Also, the previous releases were distributed on fixed media, while this release
23is being done over the web.
24The other major difference is that the third release is licensed under
25an open source agreement, which we hope will encourage people
26to experiment with it.
27.LP
28Beyond that, there are innumerable little changes throughout the code.
29Although superficially it is the same environment, there is hardly an aspect
30of the system that has not been redesigned, rewritten, or replaced.
31The following is an incomplete list of changes.
32.de Xx
33.LP
34\(bu
35..
36.Xx
37The list of architectures has changed; more compilers are included
38and the list of kernels has changed.
39There is solid support for Intel x86 multiprocessors.
40Also, although the sources are available for
41other architectures, the binaries and libraries are built only for the
42Intel x86 architectures.
43Kernel source is available for x86, Mips, DEC Alpha, and Power PC architectures.
44Compilers also exist for AMD 29000, Motorola MC68000 and MC68020,
45Intel i960, and SPARC.
46(Unlike the the last release, no SPARC kernel exists for the current system.)
47The compilers and related tools
48have been made easier to port to Unix and Windows.
49.Xx
50The kernel now has a file cache to improve I/O performance.
51Other kernel changes include the replacement of the streams interface
52with a simpler, faster, but less flexible I/O queue structure.
53The x86 kernels support PCI and PCMCIA devices.
54.Xx
55Network management has been simplified and generalized.
56DNS supports a resolver mode and the DNS server is now solid.
57DHCP is supported both at the client and server ends.
58The system can handle multiple IP stacks, which are also
59no longer Ethernet-specific.
60.Xx
61The organization of disks in the kernel has been unified, providing
62a consistent interface to all disks and controllers: SCSI or ATAPI,
63magnetic or CD-ROM.
64.Xx
65File offsets, such as in the
66.CW seek
67system call, are now 64-bit values.
68The 1995 release defined the type
69.CW Length
70for the x86 as
71.P1
72typedef union
73{
74	char	clength[8];
75	vlong	vlength;
76	struct
77	{
78		long	hlength;
79		long	length;
80	};
81} Length;
82.P2
83which is the wrong byte order.
84Now, for all architectures,
85.CW Length
86is well handled by a
87.CW vlong
88.CW long "" (
89.CW long )
90type, although for compatibility it's still held in a union:
91.P1
92typedef union
93{
94	vlong	length;
95} Length;
96.P2
97.Xx
98The kernel now maintains a file name associated with each open file or
99directory, which can be cheaply recovered by the
100.CW fd2path
101system call.
102Plan 9 now does a much better job with
103.CW ..
104(dot-dot).
105On a related note, a description of a process's name space may be
106read with the
107.CW ns
108file in
109.CW /proc ,
110or by the
111.CW ns
112command.
113.Xx
114The security model is the same, although
115the key format has changed.
116If you have an old key file, use
117.CW auth/convkeys2
118(see
119.I auth (8))
120to update it.
121There are new libraries for mulitprecision arithmetic and security.
122.Xx
123The graphics model is very different.
124It is based on the Porter-Duff compositing algebra rather than
125.CW bitblt ,
126and the system supports everything from bitmaps to true-color displays.
127Some of the graphics drivers exploit hardware acceleration.
128.Xx
129Coupled to the graphics changes, the image and font file formats have
130changed.
131They can represent a wider range of pixel formats and compress the data.
132Also the white/black sense of value is reversed (zero is now black; pixels
133represent light, not ink).
134Most of the tools can handle the old format, but they all write the new format only.
135.Xx
136The user interface now incorporates plumbing, a language-driven
137way for applications to communicate.  See
138.I plumb (6)
139for information.
140.Xx
141Building on plumbing and a program that presents the mail box as a file
142system, Plan 9 now has convenient support for MIME mail messages.
143.Xx
144.CW 8½
145has been replaced by
146.CW rio ,
147which has a similar appearance but a different architecture.
148Although still a file server, it is much more efficient: the kernel driver
149multiplexes graphics output so
150.CW rio
151is not in the display path.
152.CW Rio
153handles input and window control only.
154.Xx
155PC booting is more sophisticated.  PCs can now boot Plan 9 directly from
156the disk without running DOS.
157.Xx
158Alef is gone.
159It was deemed too difficult to maintain two sets of compilers and libraries
160for all architectures.
161Alef programs were translated into C, with the help of a new thread library
162that preserves much of Alef's functionality, but none of its syntax.
163.Xx
164Mothra is gone.  There is no web browser included in this release,
165but something may well appear before long.
166.Xx
167The
168.CW fb
169(frame buffer) suite is gone. Most of its tools are
170supplanted by new ones, such as
171.CW page ,
172.CW jpg ,
173and
174.CW togif .
175.Xx
176Also gone from this release are the games and support for
177international input
178.CW ktrans "" (
179etc.).
180Both may return.
181.Xx
182New things include an implementation of
183.CW ssh ,
184an IMAP4 server,
185and some spam-filtering software (see
186.I scanmail (8)).
187.LP
188There's lots more.
189If you have problems, mail
190.CW 9trouble@plan9.bell-labs.com .
191Please don't mail us individually.
192.LP
193Good Luck!
194