History of UNIX Source http://www.english.uga.edu/hc/unixhistoryrev.html

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History of UNIXSource http//www.english.uga.edu/
hc/unixhistoryrev.html

• 1965 Bell Labs/General Electric/MIT announced
  they were jointly developing a new OS, called
  Multics, capable of supporting upwards of 1000
  simultaneous users.
• Favorite pastime of project programmersplaying
  Space War http//lcs.www.media.mit.edu/groups/e
  l/projects/spacewar/
• 1969 Bell Labs withdraws from Multics Ken
  Thompson, Dennis Ritchie, and others (from BTL)
  cant play space war anymore.

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The solution Write a new operating system for a
PDP-7 (4K RAM) which supports the Space War game.
This new OS was to become UNIX
According to ThompsonIt was the summer of '69.
In fact, my wife went on vacation to my family's
place in California.... I allocated a week each
to the operating system, the shell, the editor,
and the assembler, to reproduce itself, and
during the month she was gone, it was totally
rewritten in a form that looked like an operating
system, with tools that were sort of known, you
know, assembler, editor, and shell .... Yeh,
essentially one person for a month
Ken Thompson and Dennis Ritchie
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• The main development tool was BCPL (Basic
  Combined Programming Language), a tool for
  compiler writing and system programming.
• Richie wrote a striped-down version of BCPL,
  and called it B.

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• 1970 BTL purchased a PDP-11 for a text
  preparation project All software was coded on
  paper tape. Unix was rewritten for this machine.
  Used by the BTL patent group.
• 1971 (November 3) first UNIX PROGRAMMERS MANUAL
  over 60 commands b, boot, cat, chdir, chmod,
  chown, cp, ls, mv, roff, wc, who

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• 1972 Ritchie rewrote B called the new language
  C
• 1973 Unix OS rewritten in C. Unix in use at 16
  sites (all within ATT/Western Electric)
• 1974 Bill Joy arrived at UC Berkley (where
  Thomson was teaching for a year). Joy didnt
  like ed (the system editor). Bill Joy rewrote
  it. Many similar events occurred. Generally BTL
  incorporated the improvements into the next
  general release.

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"Something was created at BTL. It was distributed
in source form. A user in the UK created
something from it. Another user in California
improved on both the original and the UK version.
It was distributed to the community at cost. The
improved version was incorporated into the next
BTL release.There was no way that BTL Patent
and Licensing could control this. And the system
got better and more widely used all the time."
Dennis Richie and Bill Joy (late 70s)
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• 1975 Unix leaves home BTL releases Unix
• 1977 Unix in use at 500 sites (125
  Universities)
• 1978-1984 Xenix, System III, System V, 4.2BSD,
  SVR2
• 1984 Unix in use at 100,000 sites
• 1984-1993 4.3BSD, SVR3, SVR4, XPG3, SVR4.2, 4.4BSD

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• 1991 (August 25) Linus Torvalds posts first
  message about linux
• 1991 (September) Linus Torvalds posts first
  Linux kernel

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From torvalds_at_klaava.Helsinki.FI (Linus Benedict
Torvalds)Newsgroups comp.os.minixSubject What
would you like to see most in minix? Summary
small poll for my new operating system
Message-ID lt1991Aug25.205708.9541_at_klaava.Helsink
i.FIgt Date 25 Aug 91 205708 GMT
Organization University of Helsinki Hello
everybody out there using minix - I'm doing a
(free) operating system (just a hobby, won't be
big and professional like gnu) for 386(486) AT
clones. This has been brewing since april, and is
starting to get ready. I'd like any feedback on
things people like/dislike in minix, as my OS
resembles it somewhat (same physical layout of
the file-system (due to practical reasons) among
other things). I've currently ported bash(1.08)
and gcc(1.40), and things seem to work. This
implies that I'll get something practical within
a few months, and I'd like to know what features
most people would want. Any suggestions are
welcome, but I won't promise I'll implement them
-) Linus (torvalds_at_kruuna.helsinki.fi) PS.
Yes - it's free of any minix code, and it has a
multi-threaded fs. It is NOT protable (uses 386
task switching etc), and it probably never will
support anything other than AT-harddisks, as
that's all I have -(.
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• 1995 Unix sells UnixWare to SCO
• 1995 UNIX 95 (Open Group)
• 1997 Version 2 of the Single UNIX Spec
• 1998 UNIX 98 (Open Group)
• 1999 Unix at 30 Linux 2.2 kernel released First
  LinuxWorld conferences
• 2001 Version 3 of the Single UNIX Spec