In my humble-but-correct opinion*, Linux and its
origins fit into the general topic of UNIX history
just as well as those of Research UNIX or BSD or
SVr4.2.2.2.2.2.2.2 or SunOS or IRIX or Ultrix or
Tru64-compaqted-HPSauce or whatever. It all stems
from the same roots, despite the protestations of
purists from all sides.
Warren gets final say, of course, but to encourage
him I will say: Ploooogie!
Norman Wilson
Toronto ON
* One of Peter Weinberger's sayings that I still
enjoy overusing.
> Did the non-Unix people also pull pranks like the watertower?
One of my favorites was by John Kelly, a Texas original,
who refused the department-head perk of a rug so he
could stamp his cigarettes out on the vinyl floor.
John came from Visual and Acoustics Research, where
digital signal processing pressed the frontiers of
computing. Among his publications was the completely
synthetic recording of "Daisy, Daisy" released
circa 1963.
Kelly electrified the computer center with a
blockbuster prank a year or two before that. As
was typical of many machine rooms, a loudspeaker
hooked to the low-order bit of the accumulator
played gentle white noise in the background. The
noise would turn into a shriek when the computer
got into a tight loop, calling the operators to
put the program out of its misery.
Out of the blue one day, the loudspeaker called
for help more articulately: "Help, I'm caught in
a loop. Help, I'm caught in a loop. ..." it
intoned in a slow Texas drawl. News of the talking
computer spread instantly and folks croweded into
the machine room to marvel before the operators
freed the poor prisoner.
Doug
Looking at the 6th edition man page tty(2), I see
Carriage-return delay type 1 lasts about .08 seconds and is
suitable for the Terminet 300. Delay type 2 lasts about .16
seconds and is suitable for the VT05 and the TI 700. Delay
type 3 is unimplemented and is 0.
New-line delay type 1 is dependent on the current column and
is tuned for Teletype model 37's. Type 2 is useful for the
VT05 and is about .10 seconds. Type 3 is unimplemented and
is 0.
Why would the VT05 (a VDU) need a delay for carriage return?
I can just about imagine that it might need one for linefeed
if it shifted the characters in memory.
-- Richard
--
The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.
On 2020-07-29 15:17, Paul Koning wrote:
>
>
>> On Jul 29, 2020, at 5:50 AM, Johnny Billquist <bqt(a)softjar.se> wrote:
>>
>> Just a small comment. Whoever it was that thought DECtape was a tape was making a serious mistake. DECtapes are very different from magtapes.
>>
>> Johnny
>
> Depends on what you're focusing on. Most tapes are not random-write. DECtape and EL-X1 tape are exceptional in that respect. But tapes, DECtape include, have access time proportional to delta block number (and that time is large) unlike disks.
>
> From the point of view of I/O semantics, the first point is significant and the second one not so much.
True. But seek times are in the end only relevant as an aspect of the
speed of the thing, nothing else.
However, seek times on DECtape aren't really comparable to magtape
either. Because DECtape deals with absolute block numbers. So you can
always, no matter where you are, find out where you are, and how far you
will need to move to get to the correct block.
With magtapes, this is pretty much impossible. You'll have to rewind,
and then start seeking.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt(a)softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
OK, I was able to locate 2bsd.tar.gz and spencer_2bsd.tar.gz in the
archive. Neither is an installation tape. It appears that they are just
tarballs of their respective systems (there are very minor differences
between the two).
In the TAPE file in the tarball, it talks about reading the tar program
off of the tape using:
dd if=/dev/mt0 bs=1b skip=1 of=tar
Well, tar is definitely not located at that address, which implies that
the tarball isn't a distro tape. This note in the archive used to read:
...
The remaining gzipped tar files are other 2BSD distributions supplied by
Keith Bostic, except for spencer_2bsd.tar.gz which came from Henry Spencer.
They do not contain installation tape images. The 2.9BSD-Patch directory
contains patches to 2.9BSD dated August 85, and again supplied by Keith Bostic.
...
now it reads:
...
2.11BSD 2.11BSD-pl195.tar is a copy of 2.11BSD at patch level 195, supplied
by Tom Ivar Helbekkmo. spencer_2bsd.tar.gz is a version of 2BSD which came
from Henry Spencer.
...
I recall having to do something with cont.a files, which are not present
on these images. So, my questions is, does anyone know of or have an
actual 2bsd tape/tape image?
Thanks,
Will
Here's where I found the tarballs:
https://www.tuhs.org/Archive/Distributions/UCB/
--
GPG Fingerprint: 68F4 B3BD 1730 555A 4462 7D45 3EAA 5B6D A982 BAAF
I've always been intrigued with regexes. When I was first exposed to
them, I was mystified and lost in the greediness of matches. Now, I use
them regularly, but still have trouble using them. I think it is because
I don't really understand how they work.
My question for y'all has to do with early unix. I have a copy of
Thompson, K. (1968). Regular expression search algorithm. Communications
of the ACM, 11(6), 419-422. It is interesting as an example of
Thompson's thinking about regexes. In this paper, he presents a
non-backtracking, efficient, algorithm for converting a regex into an
IBM 7094 (whatever that is) program that can be run against text input
that generates matches. It's cool. It got me to thinking maybe the way
to understand the unix regex lies in a careful investigation into how it
is implemented (original thought, right?). So, here I am again to ask
your indulgence as the latecomer wannabe unix apprentice. My thought is
that ed is where it begins and might be a good starting point, but I'm
not sure - what say y'all?
I also have a copy of the O'Reilly Mastering Regular Expressions book,
but that's not really the kind of thing I'm talking about. My question
is more basic than how to use regexes practically. I would like to
understand them at a parsing level/state change level (not sure that's
the correct way to say it, but I'm really new to this kind of lingo).
When I'm done with my stepping through the source, I want to be able to
reason that this is why that search matched that text and not this text
and why the search was greedy, or not greedy because of this logic here...
If my question above isn't focused or on topic enough, here's an
alternative set to ruminate on and hopefully discuss:
1. What's the provenance of regex in unix (when did it appear, in what
form, etc)?
2. What are the 'best' implementations throughout unix (keep it pre 1980s)?
3. What are some of the milestones along the way (major changes, forks,
disagreements)?
4. Where, in the source, or in a paper, would you point someone to
wanting to better understand the mechanics of regex?
Thanks!
Will
--
GPG Fingerprint: 68F4 B3BD 1730 555A 4462 7D45 3EAA 5B6D A982 BAAF
The Computer History Museum has an interesting blog post about
Dennis Ritchie's lost dissertation:
https://computerhistory.org/blog/discovering-dennis-ritchies-lost-dissertat…
Interesting fact is that Dennis never received his PhD because he failed
to provide a bound copy of his dissertation to the Harvard library.
Kirk McKusick
On another front. I know I've asked this before in v6, and possibly
related to v7, but I can't find the notes anywhere. vi doesn't come with
v7. So, has anybody put it on v7 in simh? I saw a thread sometime back
where vi on v7 wasn't the main topic, where Warren? I think it was, said
he'd done it and it was "easy." I don't suppose there are any notes
laying around telling how this might be accomplished?
I do see vi in 2bsd.tar, I don't suppose there is a 'how to install
2bsd on v7" note around either?
Thanks,
Will
--
GPG Fingerprint: 68F4 B3BD 1730 555A 4462 7D45 3EAA 5B6D A982 BAAF
Is there full bsdi git repo anywhere?
I've vague recollections parts were merged into FreeBSD in the early
2000s so I assume it was open sourced?
There is a tarball of bsdi 2 on venus wetware but that's the best I
can do with searching.
--
Steve Mynott <steve.mynott(a)gmail.com>
cv25519/ECF8B611205B447E091246AF959E3D6197190DD5
> "My graduate school experience convinced me that I was not smart enough to
> be an expert in the theory of algorithms and also that I liked procedural
> languages better than functional ones."
>
> Amen to that. Me too, I tried functional languages and my head hurt. C
> seems so natural to me.
Dennis made quite a generalization from a sample of one--Lisp,
the only functional language that existed when he was in grad
school. I'm sure he'd agree today that functional languages
shine for spplications rooted in algebraic domains. I
immodestly point to www.cs.dartmouth.edu/~doug/powser.html,
which has nothing to do with Unix, but certainly would have
appealed to Dennis.
Doug
