On Wed, Jan 22, 2020 at 12:55 PM Warner Losh <imp@bsdimp.com> wrote:

> I  thought the answer was "ARPANET" since we had a NCP on 4th edition Unix
> in late 1974 or early 1975 from the University of Illinois dating from that
> time (the code in TUHS appears to be based on V6 + a number of patches).
>
Because we can't ask Greg sadly, I think the Holmgren is the last around
that would know definitively and I've personally lost track of him.

That said, I don't think UofI had anything earlier than 5th edition (I
fairly sure that there were very few copies of 4th edition distributed
outside of the Bell: i.e. Columbia, NYU and I thought Harvard; but I don't
think too many more than that).  Lou Katz would be a better source than I,
but I was always under the impression that the number 5th editions, the
count was also a smaller 2 digit integer.  6th was where Unix began to
'spread' and by 7th, 'go viral.'

And to be honest, I personally thought that Steve and Greg did the ArpaNet
NCP work on V6, but it might have been v5th I suppose.  I did not know
about it until the 6th edition work.  But, they were fairly early.  BTW: I
thought the Rand PIPE code was also developed on 6th, but those also might
have been 5th.

Clem