30 Mar
2020
30 Mar
'20
3:26 p.m.
Paul - see below..
On Mon, Mar 30, 2020 at 3:43 AM Paul Ruizendaal <pnr(a)planet.nl> wrote:
To be honest, late 1981 sounds a bit too early for the
merge. The 4.1 code
was ready in June 1981 and the ’select’ system call was first proposed in
July 1981, so it is possible. However, in the BSD line ’select’ was not
fully implemented until March/April 1982.
Please be careful here. 4.1BSD is different from the pre-'4.2' released
and
4.2BSD itself. 4.1aBSD was the first pseudo release[1] that started to have
the major surgery to support Bill's sockets idea and splice in the UCB
rewrite of the BBN code. 4.1BSD was the first system for the Vax that
really wide distribution. 'Anyone' with an AT&T license could get it and
most people did. Remember this is the system that BBN (Gurwitz) did the
original IP/TCP support (sans sockets - i.e. /dev/ip /dev/tcp ...). Your
date of June '81 for the 4.1BSD release seems late, but I'll accept it.
3BSD was 1979, and I thought 4BSD was a year later, with 4.1BSD a few
months after 4BSD (few people actually got 4BSD)
That said, Bill and Sam did the heavy lifting on select(2) first in 4.1aBSD
and there were some issues (again I have forgotten the details -- I do
remember, I was working on my thesis and I had a do a huge rewrite of the
AP kernel support to handle select(2) properly). I remember talking to Sam
(arguing with him most probably) about it one night before it was fully
created. I want to say, he had worked on something similar at the firm he
was at (the firm name I now forget -- si-mumble -- they were in Mt. View)
before he joined CRSG. I don't remember now the issues I had, but I do
remember it was a bit of mess to support the way the AP hardware assumed it
could do DMA on the UBA[2]
[1] 4.1a/4.1b/4.1cBSD was officially internal to UCB and some ARPA-sites,
although I would have expected someone like Dennis in 1127 to have been
sent it also, as wnj was in the process of leaving for Sun and he took them
with him. For instance, I would take 4.1c to Masscomp. The key is that
these were not as widely distributed as 4.1BSD. 4.2BSD would really
accelerate BSD UNIX uptake, because of the networking support but there was
more than 2-3 years between 4.1BSD and 4.2BSD.
[2] The AP's MMU/DMA interface at the time, was causing me great hair, and
that was likely to have been part of the reason I wanted some help/changes
in the KPI interface - which is actually funny, they eventually came with
the CMU Mach MMU changes of 4.4BSD (which was much more friendly to a
multiprocessor/coprocessor architecture). FWIW: I never got them when I
was at UCB.