About a year ago the Research telephone switch came up on this list.
Rob Pike wrote:
"But the PBX story is correct. To demonstrate how message passing was a good
model for a switching system, in particular to make a point to the
switching systems division of Bell Labs/AT&T, Ken and Joe bought a
commercial PBX and swapped out its processor for a PDP-11/23 (I think), and
programmed it up. It was just before I arrived there but I was given the
impression it had the desired strategic influence on Indian Hill.
The feature we all loved it for was that instead of ringing the phone in
the Unix room when you got a call, it would announce your name through the
voice synthesizer: "Phone call for Ken." "Phone call for Joe". One rapidly
stopped even hearing the announcement if it didn't end with your name.”
I’ve been having an off list discussion with Bill Marshall and this PBX was influential in another way as well.
First of all, Bill can confirm that it indeed was a 11/23, the same racks were used for Datakit switches. He also remembered that the software for this PDP-11 went by the nickname of “TPC” - for Tiny Phone Company. Lee McMahon was on the team writing TPC.
The first software for the Datakit switch was written by Greg Chesson and was called “CMC” (for ‘Common Control’). There are still some references to CMC in the 8th Edition source code.
This first software was later replaced by new code designed by Lee McMahon that was modelled after TPC. This new code was named “TDK”. This, too, can be seen in the 8th Edition source. The TDK protocols for building and releasing a Datakit virtual circuit appear to have been in use into the 1990’s.
https://fingolfin.org/blog/20200327/stdio-abi.html
An interesting look at the history of stdio and subsequent ABI choices.
Cheers, Warren
--
Sent from my Android phone with K-9 Mail. Please excuse my brevity.
Thanks, everyone, for pointing out the "accident of history".
This is a little morality tale about clever programming.
Joe Ossanna would never have tokenized \s constructs that
way if the CAT typesetter had been capable of a wider
range of type sizes. Brian seems to have kept it for
backward compatibility. But groff was perfectly willing
to break backward compatibility in tokenizing command
names. Why not in \s?
I encourage Branden to go whole hog and let
\s123DEWEY WINS produce a banner headline.
Doug
> From: Warren Toomey
> Quite good
Yes.
The second part of:
"Sixth Edition sources are much more widely available than earlier versions,
thanks largely to the Lions book"
is I believe incorrect, though; I reckon it's because V6 was so widely
distributed, both inside and outside Bell. Many more copies -> higher
probability of retention.
Also, from 'Source code listing for the Lions' Commentary in PDF and PostScript':
"in 1988 I discovered an old 9-track tape being discarded of a PDP11
backup. It was hard to determine what it was running, but it did have an
intact /usr/src/ tree of which most of the files were timesamped 1979, even
at that time it seemed ancient. So it was either 7th edition or a derivative
like PWB, which I believe it was.
Do you still have the tape, or its contents?
Noel
> From: Paul Ruizendaal
> The paper is from late 1981. ... When did FIFO's become a
> standard Unix feature?
Err, V4? :-) At least, that's when pipes arrived (I think - we don't have V4
sources, but there are indications that's when they appeared), and a pipe is a
FIFO. RAND ports just allowed (effectively) a pipe to have a name in the file
system.
The implementation of both is pretty straight-forward. A pipe is just a file
which has a maximum length, after which the writer is blocked. A port is
just a pipe (it uses the pipe code) whose inode appears in the file system.
> From: Clem Cole
> I think the code is on one of the 'USENIX' tapes in Warren's archives.
Doc is here:
https://minnie.tuhs.org//cgi-bin/utree.pl?file=BBN-V6/doc/ipc
and sources for all that are here:
https://minnie.tuhs.org//cgi-bin/utree.pl?file=BBN-V6/dmrhttps://minnie.tuhs.org//cgi-bin/utree.pl?file=BBN-V6/ken
(port.c is in 'dmr', not 'ken'where it should be).
Noel
Greetings,
I was reviewing a manual page update and came across an ambiguous answer to
a question that came up, so I thought I'd ask here.
execl and execv first appear in our extant unix man pages in V4. The v3 and
v2 man pages don't have this listed at all. Case closed, right? It appeared
in V4.
However, the Dennis_v1/unix72 tree has execl.s and execv.s in them. Diving
back into the history on Warren's github account,
https://github.com/DoctorWkt/unix-jun72/tree/master/src says they come from:
"The files in lib/ come from the libc.sa file which is on the
last1120c.tar.gz
tap(I) tape image, also at the same URL, and form the C library for the
above compiler."
and
"from a working C compiler for 2nd Edition UNIX."
which suggests that it may have been in V2 or maybe even V1. It's
first use in Unix appears to be V5, but the extant pre-v5 code is so
fragmentary it's hard to know for sure. It's not mentioned in section
II or section III of v1, v2 or v3.
Does anybody know for sure, or can provide more insight into the
last1120c.tar.gz file to help disambiguate?
Warner
When I left BTL in 1983, I made a tar tape. A number of years later I
translated the tape into a file. Only recently have I wandered through it.
I don't know how many people remember Ron Hardin in the Columbus BTL
location. He was one of the smartest guys I ever met. There are lot of Ron
Hardin stories. One of his creations (as far as I know he authored it) was
a program to create Memorandums For File -- technical memorandums. My tar
tape scooped up festoon. To this day it compiles and runs happily on
Windows 10. It was written in 1978 or thereabouts. Here is an example
output:
bin$ festoon.exe
.TL
No Worthynesses
.AU "C. C. Festoon" CCF Headquarters 1584734291
.AS
A restriction had been being amicated by a convenience at the inclusion.
.AE
.MT "MEMORANDUM FOR COAT LOCKER"
.hy 1
On this occasion,
no team responsibilities could have polyesced a renewed emphasis.
A friction had penated an activation.
At the present moment in time,
an undue number of good progresses being collected together with the
populations were being proportionately fideated by
the fact that there was a data stream which was transenniesced by an
issuance being joined together with these team re
sponsibilities,
because natural basises have been veriating a partitioning.
The supplementary work should be conclusively quinquepolyated by a well
defined interfacing.
A sophisticatedness by a schedule is operated by a nature in conflict with
a correspondence under some serious discussi
ons.
It is within the realm of possibility that the effectiveness had
vicfacesced a schedule,
but there was not a necessary background information which is being
testesced by a strong interest,
and a statistical accuracy was tempoesced by the preparation.
It should be noted that a joint partnership very repeatedly aidioated this
publication of a centralized organization.
Due to the fact that there is a simplification which simply enniesced a
process,
a new technology is fluxesced from monorogatities.
It is of the utmost importance that an insurance could be putated by an
assumption.
A major advance centered about a deficiency octocessates an important
outcome.
.P
An effectation would extramicroate to the situation.
A complete revision gravated a direction.
Inasmuch as there was not a potential usefulness that cedeates by the
timely delivery,
a consideration centered around a technique was monofortated by an
integration:
.BL
.LI
There is a not unclear meterdom which had risiesced an occasion.
.LE
.P
A clamstress of this enclosedness is cludescing the hemidormity.
.P
To arrive at an approximation,
a large quantity had been chromated by a strong feeling.
Moreover,
that idea sharing was lusated by a current proposal.
Anytime that the final outcomes had been very firmly unpathesced by not
unphilaible reasonable compromises,
no serious concerns might be being sacrated by internal establishments for
the basic objectives in back of a full utili
zation.
.P
As a consequence of the fact that a total effect might vacate an easily
situational beneficial assistance,
the apparent provisioning being effectuated by a continuing difference can
have protenesced a realization of an underly
ing purpose.
A different doubtful important outcome is cludated by a capkin.
A rationale had fortated attachments.
Moreover,
this assumption had nilcoresced the continuing study.
.P
.H 1 "An Easily Added Basic Assumption Being Joined Together With A Concept
Stage"
There is not an impediment which neoated a restriction,
therefore.
A couple utilizations could morsate a great similarity at considerable
difficulties,
but an input is primescing the concept activities,
and a growing importance was hemicisesced by that beneficial assistance.
In the same connection,
these extremenesses are rather usefully ultralucesced by directions.
.SG
.NS 0
C. R. Glitch
S. A. Hobble
R. S. Limn
M. Shayegan
.NE
Ed Bradford, Ph.D. Physics, retired from IBM
BTL 1976-1983
--
Advice is judged by results, not by intentions.
Cicero
> From: Dagobert Michelsen
> the excellent book "G=C3=B6del, Escher, Bach: An Eternal Golden Braid"
> from Douglas R. Hofstadter which also gives a nice introduction into
> logic and philosopy.
IIRC, the focus of the book is how systems made out of simple components can
exhibit complex behaviours; in particular, how information-processing systems
can come to develop self-awareness.
> From: Chet Ramey
> One of the best books I read in high school.
A book on a very similar topic to GEB, which was _extremely_ important in
developing my understanding of how the universe came to be, is "Recursive
Universe", by William Poundstone, which I recommend very highly to everyone
here. It's still in print, which is really good, because it's not as well
known as it should (IMO) be. It uses an analogy with Conway's Life to explain
how the large-scale structure of the universe can develop from a random
initial state. Buy it now!
Noel
Sorry to flog this topic, but the two examples below are an
unfair comparison. What happened to the multiplications in the
second? And two of the [enter]s in the first are unnecessary.
Ironically three of the four operations in the second are
actually reverse Polish! If you had to utter sqrt first,
as we do on paper and in speech, things wouldn't look so great.
[a] [enter]
[a] [enter]
[multiply]
[b] [enter]
[b] [enter]
[multiply]
[add]
[square root]
[a]
[square]
[plus]
[b]
[square]
[square root]
Doug
