[TUHS] 2018: eighteen months to the Unix 50th anniversary

Warren Toomey wkt at tuhs.org
Wed Jan 10 20:57:58 AEST 2018

On Wed, Jan 10, 2018 at 05:53:51PM +1100, Greg 'groggy' Lehey wrote:
>> Is it fair to say 1/1/1970 is the spiritual christening and the day to
>> celebrate?
>Clearly wkt has something else in mind if he wrote "18 months".  I
>don't think 1 January 1970 had any meaning until it became the
>(currently last) epoch.

HI all, and apologies for the delay in responding. Here's a quote
from an interview that Mike Mahoney did with Ken Thompson:


    MSM: At what point did you feel you had something here?
    Thompson: Um, well, the first one was not at all multiprogrammed,
    and was almost like subroutines on the file system. The read call, the
    system read call, was in fact the call "read" of the file system and it
    was very synchronous, just subroutine call to the file systems for these
    applications. And um there was a very quick rewrite that admitted it was
    an operating system, and it had a kernel user interface that you trapped
    across. I really can’t remember what the realization was, I mean,
    the whole time span, from initially starting with...walking downstairs,
    down there with the idea that we were going to build a file system.
    MSM: When was this, do you remember the time?
    Thompson: Yeah, it was the summer of ‘69.
    MSM: Summer of ‘69 ok
    Thompson: In fact um my wife went on vacation to my family’s place
    in California to visit my parents -- we’d just had a new son in August
    ‘68 -- and uh they hadn’t seen the kid so (unclear) took the kid to
    visit my family and she was gone a month to California and I allocated a
    week each to the shell, to the operating system, the shell, the editor,
    and the assembler, to reproduce itself. During the month she was gone,
    which was in the summer of ‘69, it was totally rewritten in a form that
    looked like an operating system, with tools that were sort of known, you
    know, an assembler, an editor and a shell. If not maintaining itself,
    right on the verge of maintaining itself, to totally sever the GECOS
So, while we don't have an exact date, it's reasonable to assume that,
sometime around July 1969, Unix was at a point where it was self-hosting.

Ken is a subscriber to this list, so maybe he might be able to help 
narrow down the date.

Cheers all,

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