[TUHS] Sockets and the true UNIX

Clem Cole clemc at ccc.com
Sat Sep 23 00:32:50 AEST 2017

Paul - you made a couple of comments and asked a few questions which I'll
take a shot at best I can having been there.   Sam spent a few hours in my
apartment drinking beer and watching football, and sometimes doing laundry
much less and arguing networking stuff. (I had a washer and dryer in those
days and he had a vacuum cleaner which I borrowed from him).  Before CSRG,
Sam had been working for a networking start up in the lower bay who's name
escapes me at the moment.   IIRC they had been doing a terminal
concentrator of some type.  Previous to UCB, I had been at Tek.  Presotto
at DEC, Baden and George at Pr1me on the their 750.

Sundays were often a football and beer session, usually at Mike Carey and
my place.

On Fri, Sep 22, 2017 at 6:36 AM, Paul Ruizendaal <pnr at planet.nl> wrote:

> Could you elaborate on how Accent networking influenced Joy's sockets?
> ​ ...​

​The Accent system was definitely heavy on people's mind.   The 1979 CMU
SPICE machine proposal had made quite a splash (I should scan it, I still
have an original copy).  Bert Halstead and Gettys later told me the story
at MIT how they had a meeting when it came out and the whole tone was 'what
are we going to do what the CMU thing'​ (the result was Athena).

By the time I got Berkeley, most of the community was watching what was
going on.   The issue in the end with Accent was that they did wrote it in
Pascal and it was not done with a UNIX API base (hence Mach would be C and
build into BSD).   But Accent was the new cool system and UNIX was not
(yet) centered as the 'the' system in the DARPA community.

DARPA was still reeling from the move from the PDP-10, and a lot people
were not 100% happy with that  (we have been discussing rms's hating Unix
and still pushing ITS as an example - he was hardly the only one).   While
the VAX has the HW was officially the DARPA system, Stanford was pushing
for VMS if you remember.   Some folks want different HW from the VAX too.
CMU & MIT were pushing DARPA for the idea of person workstations (Stanford
would join that too soon after an CMU EE would do his grad work at Stanford
- Andy B and build the "SUN" -- taking the ideas from the old CMU
distributed front-end project to a level no one ever imagined).

The point is that DARPA is kinda mixed up and the politics are not as clear
as it might seem 30 years later.

Rashid had presented the ports idea and whole Accent network model at a
DARPA PI meeting at Berkeley, I want to say in the Fall 1981-ish (date may
be off by a year or two).   IIRC he gave the Berkeley systems seminar that
week too. All the UCB System people like me, had the paper and we were
abuzz about it.  Mike Powell of Cray DemOS fame, was teaching the Grad OS
course and he was mixed up in the argument; as was Bart Miller (now at U
Wisc) who was one of his students then.

Mike has us all writing different papers and proposing different ideas.   Who
specifically contributed what is hard to say at this point, although Joy
was the master craftsman and final author/implementor of what went into the
CRSG system.  At lot of test stuff was done in private code or in other UCB
OS's work.

But Joy was absolutely trying to come up with something for UNIX that would
give a lot of the functionality of the Accent in more UNIX centric manner
because he felt he needed to keep the DARPA focused on UNIX as the system
of choice.   Hence overlaying the file descriptor in the socket call while
Rashid in Mach, would leave ports as separate concept.

> ​I ​
> think this idea came from Sam Leffler, but perhaps he was inspired
> by something else (Accent?, Chaos?)
​Sam is a good friend and I give him credit for many things.  Primarily as
making sure the BSD system worked.   As I have always said about Joy, "he
types open curly brace, close curly brace and he patches faster than anyone
I have even known.​"

So, besides mopping up after Bill, the three things I know you can credit
to Sam are routed, rcp/rsh, and trailers in the headers.   Besides that, he
was in on everything, but what was his, what was Bills, what was someone's
else's is hard.

As one of my friends who did his undergrad @ MIT who was also a UCB grad
student when I there put it (describing MIT's job control that Joy swiped
and added to BSD), "Bill recognized a lot of great ideas and then peed on
them to make them smell like UCB."

> ​...​
> Last and least, when feeling argumentative I would claim that connection
> strings like "/dev/tcp/host:port" are simply parameter data blocks encoded
> in a string :^)

​Exactly... Although the way that worked, was actually a side effect/bug in

> ​...
>  Back in 1980 there seems
> ​ ​
> to have been a lot of confusion over message boundaries

​It really was before 1980.   Those of us that lived networking in the 70s,
we were still trying to figure out what was the right way to do a lot of
things.  By the early 80s we agreed we had to have it, but best known
methods were still off.    We were still fighting the wars of SNA vs.
DECnet vs Wangnet vs MAP vs YourNet vs TelCo vs ....   People had not yet
recognized Metcalfe's Law.​

Which really is an example of where engineers forget the technology is
actually driven by economics.    The 'winner' may not be the technology
that is the 'best' from 'theory.'

We forget that fact often on this list too I fear.   I know it hurts, a
number of things I have been part in my career I 'know' were 'better' than
what 'won' but it does not matter.  They were not economical.

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