[TUHS] UNIX/TS 4.x Findings

Jonathan Gray jsg at jsg.id.au
Fri Feb 10 12:54:26 AEST 2023

On Thu, Feb 09, 2023 at 01:32:21AM +0000, segaloco via TUHS wrote:
> Good day everyone, I'm emailing to start a thread on part of my larger
> UNIX/TS 4.x project that is coming to a conclusion.  Lots of info
> here, so pardon the lack of brevity.

according to Pirzada's thesis there was no UNIX/TS 4.x
nov 1978 UNIX/TS 1.0
feb 1979 UNIX/TS 1.1
sep 1979 UNIX/TS 1.2 (VAX)
early 1980 PWB and USG groups combine into
    "Microsystems and UNIX Development Laboratory"
jun 1980 UNIX Release 3.0
sep 1980 UNIX Release 3.1
mar 1981 UNIX Release 4.0
aug 1981 UNIX Release 4.1.1 for 3B-20
dec 1981 UNIX Release 4.1.2
jan 1982 System III, based on Release 3.0.1
feb 1982 UNIX Release 4.2
may 1982 UNIX Release 4.2.1
oct 1982 UNIX Release 5.0
jan 1983 System V, based on Release 5.0

"In August 1981, UNIX (denoted: 4.1.1[14]) was released for the
WECo 3B-20s processor. It was meant only for the 3B machine and was
basically 4.0 with hardware related changes.  This release also marked
the point where WECo became the official UNIX release agent (aking over
from Bell Labs).  An update (4.1.2) was released in December containing
some memory management fixes and added on-line diagnostics.

14. Release 4.1 never making it out of the door as it was not meant for
floating point hardware."

> somewhere along the way the responsibility was shifted from Lab 364 (3.x)
> to Lab 4542 (5.x).

"A Bell Laboratories -wide reorganisation in January 1981 resulted in
the UNIX Lab being renumbered. Release 4.0 was launched from this
organization in March."

> SysV IPC appears to be largely there by 4.1, with only icprm missing
> as far as I could tell.

further changed in 4.2:

"Release 4.2 was launched in February 1982 for both the 3B & the DEC
machines. It contained improvements to the data communications and
networking software and more mature IPC."

> From 4.1 to 5.0 the largest changes I see thus far are the addition of
> CB-UNIX init, generalization of COFF from a 3B-20 object format, and
> otherwise just clerical, marketing, and accuracy improvements to the

"Much improved performance, a new file system, new init and getty (from
CB/UNIX) and networking with other bits from BSD/UNIX were the main
features of Release 5.0"

quotes from:
Shamim Sharifuddin Pirzada
A Statistical Examination of The Evolution of the UNIX System
September 1988

referenced in

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