FQA 0 – Introduction To Plan 9

Plan 9 is a analysis working system from the identical group who created UNIX at
Bell Labs Computing Sciences Research Center (CSRC). It emerged within the late Nineteen Eighties, and its early improvement coincided with persevering with improvement of the later variations of
Research UNIX. Plan 9 may be seen as an try to push among the similar concepts that knowledgeable UNIX
even further
into the period of networking and graphics.
Rob Pike has described Plan 9 as “an argument” for simplicity and readability, whereas others have described it as “UNIX, solely moreso.”

From
The Use of Name Spaces in Plan 9:

Plan 9 argues that given a number of rigorously applied abstractions it
is feasible to supply a small working system that gives help
for the biggest programs on a wide range of architectures and networks.

From the
intro(1)
man web page:

Plan 9 is a distributed computing setting assembled from
separate machines appearing as terminals, CPU servers, and file
servers. A consumer works at a terminal, operating a window
system on a raster show. Some home windows are related to
CPU servers; the intent is that heavy computing must be
accomplished in these home windows however it’s also doable to compute on
the terminal. A separate file server gives file storage
for terminals and CPU servers alike.

The 2 most vital concepts in Plan 9 are:

•
private namespaces (every course of constructs a novel view of the hierarchical file system)

•
file interfaces (acquainted from UNIX, however taken to the acute: all assets in Plan 9 seem like file programs)

Most the whole lot else within the system falls out of those two primary concepts.

Plan 9 actually pushes laborious on some concepts that Unix has that haven’t
actually been totally developed, particularly, the notion that almost
the whole lot within the system is accessible by a file. In different
phrases, issues seem like an extraordinary disk file. So all of the gadgets are
managed this manner by way of ASCII strings, not sophisticated information
constructions. For instance, you make community calls by writing an ASCII
string, not the information. This notion is one thing that’s truly
leaking fairly quick.

The second factor is kind of extra delicate and kind of laborious to understand
till you’ve truly performed with it. That’s that the set of information
a person program can see depends upon that program itself. In a
commonplace form of system, both with Unix distant file programs or
Home windows hooked up file programs, all of the packages operating within the machine
see the identical factor. In Plan 9, that’s adjustable per program. You
can arrange specialised title stations which can be distinctive to a selected
program. I imply, it’s not related to this system itself however with
the method, with the execution of the method.

Learn:
intro(1);
Plan 9 from Bell Labs;
Designing Plan 9,
initially delivered on the
UKUUG Conference in London, July 1990; and
FQA 7 – System Management;
for a extra detailed overview of Plan 9’s design.

As we speak, Plan 9 continues in its unique type, in addition to in a number of derivatives and forks.

The US of Plan 9

Plan 9 from Bell Labs — The unique Plan 9. Successfully lifeless, all of the builders have been run out of the Labs and/or are on show at Google.

Plan 9 from User Space — Plan 9 userspace ported/imitated for UNIX (particularly OS X).

9legacy — David du Colombier’s cherry picked assortment of patches from numerous folks/forks to Bell Labs Plan 9. (It’s not a fork.)

9atom — Erik Quanstrom’s fork of Plan 9, maintained to Erik’s wants and infrequently pilfered by 9front.

9front — (that’s us) (we rule (we’re the tunnel snakes))

NIX — Excessive efficiency cloud computing is NIX — imploded in a cloud of political acrimony and retarded bureaucratic infighting.

NxM — A kernel for manycore programs — by no means noticed within the wild.

Clive — A brand new working system from Francisco J. Ballesteros, designed to generate grantwriting apply materials and analysis initiatives for in any other case indolent college students.

Akaros — Akaros is an open supply, GPL-licensed working system for manycore architectures. Has no bearing on something however has attracted grant cash.

Harvey — Harvey is an effort to get the Plan 9 code working with gcc and clang.

Inferno — Inferno is a distributed working system began at Bell Labs, however is now developed and maintained by
Vita Nuova Holdings as free software program. Simply kidding it isn’t developed or maintained.

ANTS — Superior Namespace Instruments for Plan 9. ANTS is a set of modifications and extra software program which provides new namespace manipulation capabilities to Plan 9.

Jehanne — Jehanne:Harvey::William King Harvey:J. Edgar Hoover

Plan 9 Foundation — Now providing downloads of historic Plan 9 releases.

Within the phrases of the
Bell Labs Plan 9 wiki:

Plan 9 is just not Unix. In case you consider it as Unix, you might change into
annoyed when one thing doesn’t exist or when it really works in another way
than you anticipated. In case you consider it as Plan 9, nevertheless, you’ll discover
that the majority of it really works very easily, and that there are some really
neat concepts that make issues a lot cleaner than you’ve got seen earlier than.

Confusion is compounded by the truth that many UNIX instructions exist on Plan 9 and behave in related methods. In truth, a few of Plan 9’s userland (such because the
upas
mail interface, the
sam
textual content editor, and the
rc
shell) are carried over immediately from
Research UNIX 10th Edition. Additional investigation reveals that many concepts present in Plan 9 have been explored in additional primitive type within the later editions of
Research UNIX.

Nevertheless, Plan 9 is a totally new working system that makes no try to evolve to previous prejudices. The purpose of the train (circa the late Nineteen Eighties) was to keep away from previous issues and discover new territory. Plan 9 is just not UNIX
for a motive.

Learn:
UNIX to Plan 9 translation (wiki.9front.org),
UNIX to Plan 9 command translation (9p.io),
UNIX Style, or cat -v Considered Harmful

Plan 9 from User Space (also referred to as plan9port or p9p) is a port of many Plan 9 from Bell Labs libraries and functions to UNIX-like working programs. At present it has been examined on a wide range of working programs together with: Linux, Mac OS X, FreeBSD, NetBSD, OpenBSD, Solaris and SunOS.

Plan9port consists of a mixture of principally unaltered Plan 9 userland utilities packaged alongside numerous makes an attempt to mimic Plan 9’s kernel intefaces utilizing miscellaneous obtainable UNIX packages and instructions. Among the imitations are extra profitable than others. In all, plan9port doesn’t precisely symbolize the expertise of utilizing precise Plan 9, however does present sufficient performance to make some customers content material with operating acme on their Macbooks.

It’s now being
slowly ported to the Go programming language.

Inferno is a distributed working system additionally created at Bell Labs, however which is now developed and maintained by
Vita Nuova Holdings as free software program. It employs many concepts from Plan 9 (Inferno does share some appropriate interfaces with Plan 9, together with the
9P/Styx protocol), however is a totally totally different OS. Many customers new to Plan 9 discover out about Inferno and instantly resolve to desert Plan 9 and its opaque consumer interface for this clearly “extra superior” sibling, however often abandon that, too, upon first contact with Inferno’s Tk GUI. Notable exceptions duly famous.

See:
http://www.xs4all.nl/~mechiel/inferno/

See:
http://harmful.cat-v.org/software/

Then again, the roaring 2020s have seen Plan 9 sprout a considerable presence on social media, so in the event you’re right here for that, YMMV.

You might ask your self, properly, how did I get right here? Within the phrases of Plan 9 contributor
Russ Cox:

Why Plan 9 certainly. Isn’t Plan 9 simply one other Unix clone? Who cares?


Plan 9 presents a constant and simple to make use of interface. When you’ve
settled in, there are only a few surprises right here. After I switched to
Linux from Home windows 3.1, I seen all method of inconsistent habits
in Home windows 3.1 that Linux didn’t have. Switching to Plan 9 from
Linux highlighted simply as a lot in Linux.


One motive Plan 9 can do that is that the Plan 9 group has had the
luxurious of getting a complete system, so issues may be mounted and
options added the place they belong, somewhat than the place they are often. For
instance, there is no such thing as a tty driver within the kernel. The window system
handles the nuances of terminal enter.


If Plan 9 was only a actually clear Unix clone, it is perhaps price utilizing,
or it won’t. The neat issues begin occurring with user-level file
servers and per-process namespace. In Unix, /dev/tty refers back to the
present window’s output gadget, and means various things to
totally different processes. This can be a particular hack enabled by the kernel for
a single file. Plan 9 gives full-blown per-process namespaces. In
Plan 9 /dev/cons additionally refers back to the present window’s output gadget,
and means various things to totally different processes, however the window
system (or telnet daemon, or ssh daemon, or no matter) arranges this,
and does the identical for /dev/mouse, /dev/textual content (the contents of the
present window), and so on.


Since items of file tree may be offered by user-level servers, the
kernel needn’t find out about issues like DOS’s FAT file system or
GNU/Linux’s EXT2 file system or NFS, and so on. As a substitute, user-level servers
present this performance when desired. In Plan 9, even FTP is
offered as a file server: you run ftpfs and the information on the server
seem in /n/ftp.


We’d like not cease at bodily file programs, although. Different file servers
synthesize information that symbolize different assets. For instance, upas/fs
presents your mail field as a file tree at /mail/fs/mbox. This fashions
the recursive construction of MIME messages particularly properly.


As one other instance, cdfs presents an audio or information CD as a file
system, one file per monitor. If it’s a writable CD, copying new information
into the /mnt/cd/wa or /mnt/cd/wd directories does create new audio or
information tracks. Wish to fixate the CD as audio or information? Take away certainly one of
the directories.


Plan 9 matches properly with a networked setting, information and listing
bushes may be imported from different machines, and all assets are information
or listing bushes, it’s straightforward to share assets. Wish to use a
totally different machine’s sound card? Import its /dev/audio. Wish to debug
processes that run on one other machine? Import its /proc. Wish to use
a community interface on one other machine? Import its /internet. And so forth.


Russ Cox

https://9p.io/wiki/plan9/what_do_people_like_about_plan_9/index.html

Learn:
How I Switched To Plan 9

See:
FQA 8 – Using 9front

John Floren gives a humorous(?) overview of
a typical new user’s reactions to Plan 9:

Hello! I’m new to Plan 9. I’m actually excited to work with this
new Linux system.


I hit some questions.


1 How do I run X11?


2 The place is Emacs?


3 The code is bizarre. It doesn’t seem like GNU C in any respect.
Did the individuals who wrote Plan 9 find out about C?


4 I attempted to run mozilla however it didn’t work. How come?

Is that this man you?

Associated:
http://9front.org/buds.html

http://c2.com/cgi/wiki?WhatIsNotInPlanNine

Russ Cox:

I ran Plan 9 from Bell Labs as my day after day work setting till
round 2002. By then two information have been painfully clear. First, the
Web was right here to remain; and second, Plan 9 had no hope of retaining
up with net browsers. Porting Mozilla to Plan 9 was far an excessive amount of
work, so as an alternative I ported virtually all of the Plan 9 consumer stage software program to
FreeBSD, Linux, and OS X.

Russ Cox
(again):

The usual arrange for a Plan 9 aficionado right here appears to
be a Mac or Linux machine operating Plan 9 from Person Area
to get at sam, acme, and the opposite instruments. Rob, Ken, Dave, and I
use Macs as our desktop machines, however we’re a little bit of an exception.
Most Google engineers use Linux machines, and I do know of
fairly a number of ex-Bell Labs people who find themselves completely satisfied to be utilizing
sam or acme on these machines. My very own setup is 2
screens. The primary is a regular Mac desktop with non-Plan 9
apps and a handful of 9terms, and the second is a full-screen
acme for getting work accomplished. On Linux I do the identical however the
first display is a Linux desktop operating rio (previously dhog’s 8½).


Extra broadly, each few months I are inclined to get an e-mail from
somebody who’s completely satisfied to have simply found that sam remains to be
maintained and obtainable for contemporary programs. A number of the time
these are individuals who solely used sam on Unix, by no means on Plan 9.
The plan9port.tgz file was downloaded from 2,522 distinctive
IP addresses in 2009, which I think is many greater than
Plan 9 itself. In that sense, it’s very nice to see the instruments
getting a a lot wider publicity than they used to.


I haven’t logged into an actual Plan 9 system in a few years,
however I take advantage of 9vx sometimes after I wish to remind myself how
an actual Plan 9 software labored. It’s at all times good to be again,
nevertheless briefly.


Russ

Russ Cox
continues:

> Are you able to briefly inform us why you (Russ, Rob, Ken and Dave)


> now not use Plan9 ?


> Due to lacking apps or due to lacking driver to your {hardware} ?


> And do you continue to use venti ?


Working programs and programming languages have
sturdy community results: it helps to make use of the identical system
that everybody round you is utilizing. In my group at MIT,
that meant FreeBSD and C++. I ran Plan 9 for the primary
few years I used to be at MIT however gave up, as a result of the dearth of
a shared system made it too laborious to collaborate.
Once I switched to FreeBSD, I ported all of the Plan 9 libraries
and instruments so I might hold the remainder of the consumer expertise.


I nonetheless use venti, in that I nonetheless keep the venti server that
takes care of backups for my previous group at MIT. It makes use of
the plan9port venti, vbackup, and vnfs, all operating on FreeBSD.
The venti server itself was my final actual Plan 9 set up.
It’s Coraid {hardware}, however I stripped the software program and had put in
my very own Plan 9 kernel to run venti on it immediately. However earlier than
I left MIT, the very last thing I did was reinstall the machine utilizing
FreeBSD in order that others might assist hold it updated.


If I wasn’t interacting with anybody else it’d be good to maintain
utilizing Plan 9. But it surely’s additionally good to have the ability to use off the shelf
software program as an alternative of reinventing wheels (9fans runs on Linux)
and to have good {hardware} help accomplished by different folks
(I can shut my laptop computer and it goes to sleep, and even higher,
after I open it once more, it wakes up!). With the ability to get these
issues and nonetheless hold a lot of the Plan 9 consumer expertise by
operating Plan 9 from Person Area is a compromise, however one
that works properly for me.


Russ

Rob Pike:

What Russ says is true however for me it was less complicated. I used Plan 9 as my
native working system for a yr or so after becoming a member of Google, however it
was simply too inconvenient to stay on a machine and not using a C++ compiler,
with out good NFS and SSH help, and particularly and not using a net
browser. I switched to Linux however discovered it very buggy (the primary
drawback was most certainly a foul graphics board and/or driver, however nonetheless)
and my principal collaborator (Robert Griesemer) had accomplished the bottom work
to get a Mac working as a main machine inside Google, and Russ had
plan9port up, so I pushed plan9port onto the Mac and have been there
ever since, fairly fortunately. These days Apples are formally supported
so it’s change into straightforward, workwise.


I miss a number of what Plan 9 did for me, however the considerations at work override that.


-rob

https://www.muckrock.com/foi/united-states-of-america-10/foia-cia-plan-9-from-bell-labs-82547/

From: Rob Pike <robpike@gmail.com>

Date: Wed, 22 Jun 2022 12:58:15 +1000

Topic: [TUHS] Re: forgotten variations

The Plan 9 CD-ROM wanted about 100MB for the full distribution, if that. We

hatched a plan to fill up the relaxation with encoded music and embrace the

software program to decode it. (We needed to get the encoder out too, however legal professionals

stood in the means. Hold studying.) Utilizing connections I had with of us in the

space, and some very useful pals in the music enterprise, I bought permission

to distribute a number of hours of present recorded stuff from teams like the

Residents and Wire. Lou Reed gave a couple of items too – he was very

See Also



The Thriller of Sudden Genius

 in Ken and Sean’s work (which, it ought to be famous, was constructed on

groundbreaking work accomplished in the acoustics heart at Bell Labs) and visited

us to verify it out. Debby Harry even recorded an unique tune for us in

the studio.

We had permission for all this of course, and releases from everybody

concerned. It was very thrilling.

So naturally, simply earlier than launch, an asshole (I am being variety) lawyer at

AT&T headquarters in Manhattan stopped the undertaking chilly. In a cellphone name

that handled me as shabbily as I have ever been, he stated he didn’t know who

these “assholes” (once more, however this time his time period) have been and due to this fact the

releases have been meaningless as a result of anybody might have written them.

And that, my pals, is why MP-3 took off as an alternative of the far higher

follow-on system we have been on the cusp of getting out the door.

-rob

P.S. No, I don’t have the music any extra. Too unhappy to hold.

0.2.4 – What’s the take care of Plan 9’s bizarre license?

Through the years Plan 9 has been launched beneath numerous licenses, to the consternation of many.

The primary version, launched in 1992, was made obtainable solely to universities. The method for buying the software program was convoluted and liable to clerical error. Many potential customers had bother acquiring it inside an inexpensive timeframe and plenty of complaints have been voiced on the eventual
Plan 9 Internet mailing list.

The second version, launched in 1995 in book-and-CD type beneath a comparatively commonplace industrial license, was obtainable by way of mailorder in addition to by a particular phone quantity for a value of roughly $350 USD. It was definitely simpler to accumulate than the primary version, however many potential customers nonetheless complained that the value was too excessive and that the license was too restrictive.

Within the yr 2000, the third version of Plan 9 was lastly launched beneath a customized “open supply” license, the
Plan 9 License. Richard Stallman was not impressed:

Once I noticed the announcement that the Plan 9 software program had been launched
as “open supply”, I questioned whether or not it is perhaps free software program as properly.
After finding out the license, my conclusion was that it isn’t free; the
license incorporates a number of restrictions which can be completely unacceptable for
the Free Software program Motion. (See
http://www.gnu.org/philosophy/free-sw.html

Learn extra right here:

http://www.linuxtoday.com/developer/2000070200704OPLFSW

Within the yr 2002, the fourth version of Plan 9 was launched beneath the
Lucent Public License. This time, Theo de Raadt was not impressed:

The brand new license is completely unacceptable to be used in a BSD undertaking.


Truly, I’m astounded that the OSI would declare such a license
acceptable.


That isn’t a license which makes it free. It’s a *contract* with
penalties; let me be clear — it’s a contract with penalties
that I’m unwilling to simply accept.

Learn extra right here:

http://9fans.net/archive/2003/06/270

In 2014, parts of the Plan 9 supply code have been once more re-licensed, this time beneath the
GPLv2, for distribution with the
University of California, Berkeley’s Akaros working system. Predictably, numerous events weren’t impressed.

Russ Cox tried to make sense of the scenario by commenting in a
Hacker News thread:

Whenever you ask “why did large firm X make unusual selection Y concerning
licensing or IP”, 99 occasions out of 100 the reply is “legal professionals”. If the Plan
9 group had had its means, Plan 9 would have been launched totally free beneath a
trivial MIT-like license (the one used for different items of code, just like the
one true awk) in 2003 as an alternative of making the Lucent Public License. Or in
2000 as an alternative of making the “Plan 9 License”. Or in 1995 as an alternative of as a
$350 e book+CD that got here with a license to be used by a complete “group”.
Or in 1992 as an alternative of being a restricted tutorial launch.


Fortunately I’m not at Lucent anymore and am not aware about the tortured
negotiations that ended up on the clearly inelegant compromise of “The
College of California, Berkeley, has been authorised by Alcatel-Lucent
to launch all Plan 9 software program beforehand ruled by the Lucent Public
License, Model 1.02 beneath the GNU Normal Public License, Model 2.” However
the chances are overwhelming that the one-word reply is “legal professionals”.

Some have steered that confusion about licensing might have contributed to Plan 9’s failure to supplant UNIX within the wider computing world.

Any additions or modifications (as recorded in git historical past) made by 9front are offered beneath the phrases of the MIT License, reproduced within the file
/lib/legal/mit,
until in any other case indicated.

Learn:
/lib/legal/NOTICE.

In 2021, the
Plan 9 Foundation (aka P9F—no relation) satisfied Nokia to
re-license all historic editions of the Plan9 supply code beneath the MIT Public License.

As a consequence,
all
of 9front is now offered beneath the MIT License until in any other case indicated.

Re-read:
/lib/legal/mit

0.2.4.6 – Plan 9 is a registered trademark of SouthSuite Inc.

-Plan 9 is a trademark of Lucent Applied sciences Inc.

+Plan 9 is a registered trademark of SouthSuite Inc.

https://github.com/plan9foundation/plan9/commit/9db62717612a49f78a83b26ff5a176971c6cdd18.diff

Brantley Coile seen the Plan 9 trademark expired and acquired it on November 25, 2020. It was earlier than the switch of the Plan 9 copyrights to the Plan 9 Basis (March 23, 2021).
— 0intro,
https://news.ycombinator.com/item?id=26946830

Tutorial papers that describe the Plan 9 working system can be found right here:

http://doc.cat-v.org/plan_9/

Section (1) for normal publicly accessible instructions.

Section (2) for library capabilities, together with system calls.

Section (3) for kernel gadgets (accessed by way of bind(1)).

Section (4) for file companies (accessed by way of mount).

Section (5) for the Plan 9 file protocol.

Section (6) for file codecs.

Section (7) for databases and database entry packages.

Section (8) for issues associated to administering Plan 9.

The official web site for the Plan 9 undertaking is positioned at:
https://9p.io/wiki/plan9

The official web site for the Plan 9 Basis is positioned at:
http://p9f.org

The 9front fork of Plan 9 (that’s us):
http://9front.org

A neighborhood wiki setup by 9front customers:
http://wiki.a-b.xyz

A lot different precious info may be discovered at
http://cat-v.org concerning facets of UNIX, Plan 9, and software program on the whole.

Introduction to OS Abstractions Using Plan 9 From Bell Labs,
by
Francisco J Ballesteros (nemo)

Notes on the Plan 9 3rd Edition Kernel,
by
Francisco J Ballesteros (nemo)

The UNIX Programming Environment,
by
Brian W. Kernighan (bwk) and
Rob Pike (rob) (this e book is essentially the most clear, concise and eloquent expression of the Unix and ’software’ philosophies up to now)

9FRONT DASH 1
(the doc you’re studying proper now, however in e book type)

FQA INDEX |
FQA 0 – Introduction To Plan 9 |
FQA 1 – Introduction To 9front