oldest Unix machine(s)

[Henry Spencer]

Well, the mail about still-operational ancient Unix machines has petered
out, so here's the summary of results that I promised.  For the purposes
of terminology in this article, I will pretend that Bell-System divestiture
didn't happen, since virtually all the events in question happened before
the breakup.

The oldest still-running Unix machine is unquestionably within the Bell
System.  The Murray Hill research lab long since put its old machines
out to pasture, but there are some very old applications machines still
operational.

In particular, there are machines still running Cosnix, which was a hacked
derivative of the assembly-language Unix (V3).  Obviously these are not
now used much as development machines, but as turnkey applications systems.
Incidentally, some, possibly all, of the applications are written in the
old "fc" semi-interpretive Fortran!  11/45 number 570 (numbers started at
100, Research's 45 was 110) is still running Cosnix at Bell Labs Whippany.
There is a still-older Cosnix machine in the Bell System 8th-Street site
in LA; it was installed in late 72 or early 73.	 Considering the timing,
this might be an 11/20 rather than a 45.  This would appear to be the
Grand Prize winner for oldest Unix still operating.

Outside the Bell System, the picture is less clear.  Unix license number
one went to Columbia, but this may not be too significant; I don't have
dates for the licenses, and in any case license dates don't necessarily
correlate with operational dates.  Of the people I actually got responses
from, it would appear to be a three-way tie, all for V4 in late 1973,
between U of Alberta (11/45 #315, still running), Johns Hopkins U (11/45
#493, given to Chemistry Dept. but believed still running), and the Cooper
Union for the Advancement of Science and Art (a small NYC engineering
school) (11/45, #???, still running, possibly still V4!).

Corrections and addenda would be appreciated.

Thanks to all the people who replied with information, notably Dennis
Ritchie and John Mashey for the info on the Cosnix systems.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry