20 Jan
2020
20 Jan
'20
8:28 p.m.
I reposted the original Unix quiz, which disappeared when public Google
Plus was turned off. Answers will reappear in a few days.
https://commandcenter.blogspot.com/2020/01/unix-quiz.html
-rob
20 Jan
20 Jan
9:06 p.m.
On Jan 20, 2020, at 1:28 PM, Rob Pike <robpike(a)gmail.com> wrote:
I reposted the original Unix quiz, which disappeared
when public Google Plus was turned off. Answers will reappear in a few days.
https://commandcenter.blogspot.com/2020/01/unix-quiz.html
<https://commandcenter.blogspot.com/2020/01/unix-quiz.html>
I am slightly terrified that I can answer a non-trivial fraction (though by no means a
majority!) of these without looking up answers.
The TSO one in particular I knew instantly and it’s still quite true.
I don’t know the story behind #23 but I certainly want to.
Adam
22 Jan
22 Jan
9:31 a.m.
The answers are up:
https://commandcenter.blogspot.com/2020/01/unix-quiz-answers.html
-rob
2:57 p.m.
The quiz and answers were also printed in the Australian Unix User's Group
Newsletter, volume 5, numbers 5 and 6, respectively. It looks like that
might also have been copied from ';login:'? It's unclear to me.
I appreciate the additional commentary, though. Obviously some of these are
very site-specific (Chesson's phone extension, for example).
The "Who wrote the Bourne shell?" question kind of reminds me of the old
Bugs Bunny bit where he'd be on some radio gameshow and the host would ask,
"Who's buried in Grant's Tomb?" and no one would get it right.
(Except
totally different because, of course, no one is buried in Grant's Tomb:
Grant and his wife are entombed in sarcophagi above ground, not buried
below.)
Btw, the answer for #16 is `cagbef`: but `g` is not an option. I would
think the answer would be `cafbde`. Apparently in the original, option
'(d)' is missing; one imagines that was to trick the unwary who failed to
adequately read the question.
- Dan C.
On Wed, Jan 22, 2020 at 4:32 AM Rob Pike <robpike(a)gmail.com> wrote:
The answers are up:
https://commandcenter.blogspot.com/2020/01/unix-quiz-answers.html
-rob
5:54 p.m.
On Wed, Jan 22, 2020 at 7:59 AM Dan Cross <crossd(a)gmail.com> wrote:
Btw, the answer for #16 is `cagbef`: but `g` is not an
option. I would
think the answer would be `cafbde`. Apparently in the original, option
'(d)' is missing; one imagines that was to trick the unwary who failed to
adequately read the question.
I think this is wrong:
16. Q: Sort the following into chronological order: a) PWB 1.2, b) V7, c)
Whirlwind, d) System V, e) 4.2BSD, f) MERT.
A: cagbef
Whirlwind is a ringer.
So the MERT ACM paper is 1975. The BSTJ is July/Aug 1978 (received Feb
1978). Somewhere I read (don't have a handy reference for it) that MERT
ported V4 as a supervisor process which puts it in 1974 or so. In any
event, this predates everything except Whirlwind which I can't find a paper
for.
PWB 1.2 is based on V6 + stuff. PWB 1.0 was released 1977, but we don't
have an extant 1.2 tape to verify dates with, but 1978 wouldn't be
unreasonable.
We know 7th Edition was released Jan 1979 (PWB 2.0 was released, 1980
sometime)
System V was released January 1983
4.2BSD was released September 1983 (4.1c was released in 1982 though :)
So that would make the right answer c f a b d e
Even DMERT for the 3B20 was released in January 1983 (or the IEEE paper for
it was released then), so it can't be last.
I also have questions about this:
81. Q: What was the first Unix network?
A: spider
You thought it was Datakit, didn't you? But Sandy Fraser had an earlier
project.
When did Alexander G Fraser's spider cell network happen? For that matter,
when did Datakit happen? I can't find references to either start date on
line (nor anything on spider except for references to it in Dr Fraser's
bio). I can find references to Datakit in 1978 or so.
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).
Warner
- Dan C.
On Wed, Jan 22, 2020 at 4:32 AM Rob Pike <robpike(a)gmail.com> wrote:
> The answers are up:
>
> https://commandcenter.blogspot.com/2020/01/unix-quiz-answers.html
>
> -rob
>
>
6:01 p.m.
On Wed, Jan 22, 2020 at 10:54:08AM -0700, Warner Losh wrote:
On Wed, Jan 22, 2020 at 7:59 AM Dan Cross
<crossd(a)gmail.com> wrote:
If not anything else, at least because there is no option g... :)
But I might have missed a joke here?
HND
Btw, the answer for #16 is `cagbef`: but `g` is
not an option. I would
think the answer would be `cafbde`. Apparently in the original, option
'(d)' is missing; one imagines that was to trick the unwary who failed to
adequately read the question.
I think this is wrong:
16. Q: Sort the following into chronological order: a) PWB 1.2, b) V7, c)
Whirlwind, d) System V, e) 4.2BSD, f) MERT.
A: cagbef
Whirlwind is a ringer.
6:21 p.m.
On Wed, Jan 22, 2020 at 12:55 PM Warner Losh <imp(a)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
7:42 p.m.
On Wed, Jan 22, 2020 at 11:21 AM Clem Cole <clemc(a)ccc.com> wrote:
On Wed, Jan 22, 2020 at 12:55 PM Warner Losh <imp(a)bsdimp.com> wrote:
The publication date for the ACM paper is November 1975. I think I misspoke
and you are right. The 4th edition was Nov 73, and 5th Edition was June 74
(6th was June 75). In order to meet deadlines for ACM publication, it most
likely was 5th Edition, but there's also earlier references to it.
That said, I don't think UofI had anything earlier than 5th edition (I
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.
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.'
Berkeley's license was executed in January 74, so it might be on the list,
unless there was a big delay.
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.
The code we have is from the 6th edition (judging by diffs, though there's
some weird quirks between it and Dennis_v6, as well as a number of local
patches).
In addition to the Nov 1975 CACM paper, there's CAC 155, published by the
University of Illinois on 3/15/75 which pre-dates the 6th edition by a few
months. You can read it here
https://www.ideals.illinois.edu/bitstream/handle/2142/32547/networkunixsyst…
if
you'd like. There's also CAC 177, which covers the period of Jan 1, 1974 to
Dec 31, 1974 which references that Unix had been enhanced to add this after
the contract periopd. This this report may have been issued after CAC 155
and may not be proof of an earlier date (though the issue date in its
metadata in https://www.ideals.illinois.edu/handle/2142/34150 is 31 DEC
1974, it also reports activity through the end of the year so likely was
written later). There's also CAC 162 dated May 15, 1975 (
https://www.ideals.illinois.edu/handle/2142/32293) that references UNIX
talking to the mulix machine via the ARPANET protocols.
RFC 681, dated March 18th, 1975, is another instance of an edited CAC 155
report (it seems, I've not looked at them exactly, just a quick glance)
that talks about this work. It's the earliest mention of Unix in an RFC
(the next one isn't until 2 years later for an email address for Dave
Crocker DCrocker@Rand-Unix in RFC 724 in May 1977 after which it explodes
in references).
Warner
8:42 p.m.
On Wed, Jan 22, 2020 at 2:42 PM Warner Losh <imp(a)bsdimp.com> wrote:
Berkeley's license was executed in January 74, so it might be on the list,
unless there was a big delay.
That makes sense.
In addition to the Nov 1975 CACM paper, there's
CAC 155, published by the
University of Illinois on 3/15/75 which pre-dates the 6th edition by a few
months. You can read it here
https://www.ideals.illinois.edu/bitstream/handle/2142/32547/networkunixsyst…
if
you'd like.
Thanks, that tells us it was 5th (BTW the PDF is missing page 1 in the scan
- although I suspect the missing info can be gleaned from RFC 681)
BTW: There is another hint in CAC 155/RFC 681. The line on page 2 that
reads: "since the user is allowed only sixteen open files." My memory is
V6 allowed more than 16, over 20 is my memory; but we would have to look at
the structure to see what it is defined as.
RFC 681, dated March 18th, 1975, is another instance of an edited CAC 155
report (it seems, I've not looked at them exactly, just a quick glance)
that talks about this work. It's the earliest mention of Unix in an RFC
(the next one isn't until 2 years later for an email address for Dave
Crocker DCrocker@Rand-Unix in RFC 724 in May 1977 after which it explodes
in references).
And that pretty much syncs with my memory of the time.
11:10 p.m.
I think the 'd' slipped in during some editing. I've removed it. cagbef it
is.
Don't confuse quiz answers with absolute truth. All history is fiction to
some extent.
-rob
On Thu, Jan 23, 2020 at 7:43 AM Clem Cole <clemc(a)ccc.com> wrote:
On Wed, Jan 22, 2020 at 2:42 PM Warner Losh <imp(a)bsdimp.com> wrote:
Berkeley's license was executed in January 74, so it might be on the
list, unless there was a big delay.
That makes sense.
In addition to the Nov 1975 CACM paper,
there's CAC 155, published by the
University of Illinois on 3/15/75 which pre-dates the 6th edition by a few
months. You can read it here
https://www.ideals.illinois.edu/bitstream/handle/2142/32547/networkunixsyst…
if
you'd like.
Thanks, that tells us it was 5th (BTW the PDF is missing page 1 in the
scan - although I suspect the missing info can be gleaned from RFC 681)
BTW: There is another hint in CAC 155/RFC 681. The line on page 2 that
reads: "since the user is allowed only sixteen open files." My memory
is V6 allowed more than 16, over 20 is my memory; but we would have to look
at the structure to see what it is defined as.
RFC 681, dated March 18th, 1975, is another instance of an edited CAC 155
report (it seems, I've not looked at them exactly, just a quick glance)
that talks about this work. It's the earliest mention of Unix in an RFC
(the next one isn't until 2 years later for an email address for Dave
Crocker DCrocker@Rand-Unix in RFC 724 in May 1977 after which it
explodes in references).
And that pretty much syncs with my memory of the time.
11:34 p.m.
On Wed, Jan 22, 2020 at 1:42 PM Clem Cole <clemc(a)ccc.com> wrote:
BTW: There is another hint in CAC 155/RFC 681. The
line on page 2 that
reads: "since the user is allowed only sixteen open files." My memory
is V6 allowed more than 16, over 20 is my memory; but we would have to look
at the structure to see what it is defined as.
Looking at the source in the archives for V5, we see that param.h has "#define
NOFILE 15" and for V6 we see "#define NOFILE 15 /* max open files per
process */". V7 has "#define NOFILE 20 /* max open files per process */"
though, so maybe you are thinking of V7 bumping the limit to 20? Or maybe
it was a local change for MIT, since param.h could be edited... But in any
event, I think this means that the CAC 155 reference to 16 files just means
V6 or earlier.
However, I just noticed there's more direct evidence for it being based on
V5. On page 2 of CAC 155 we see
"For further information concerning the different I/O calls the reader is
directed to The UNIX Programmer's Manual, fifth edition, K. Thompson and D.
M. Ritchie, June 1974."
BTW, CAC 155 is the PDF we have linked from the early network page. I
hadn't noticed before now, but seeing the missing page refreshes my
recollection.
Warner
11:42 p.m.
👍
On Wed, Jan 22, 2020 at 6:35 PM Warner Losh <imp(a)bsdimp.com> wrote:
On Wed, Jan 22, 2020 at 1:42 PM Clem Cole <clemc(a)ccc.com> wrote:
--
Sent from a handheld expect more typos than usual
BTW: There is another hint in CAC 155/RFC 681.
The line on page 2 that
reads: "since the user is allowed only sixteen open files." My memory
is V6 allowed more than 16, over 20 is my memory; but we would have to look
at the structure to see what it is defined as.
Looking at the source in the archives for V5, we see that param.h has "#define
NOFILE 15" and for V6 we see "#define NOFILE 15 /* max open files per
process */". V7 has "#define NOFILE 20 /* max open files per process */"
though, so maybe you are thinking of V7 bumping the limit to 20? Or maybe
it was a local change for MIT, since param.h could be edited... But in any
event, I think this means that the CAC 155 reference to 16 files just means
V6 or earlier.
However, I just noticed there's more direct evidence for it being based on
V5. On page 2 of CAC 155 we see
"For further information concerning the different I/O calls the reader is
directed to The UNIX Programmer's Manual, fifth edition, K. Thompson and D.
M. Ritchie, June 1974."
BTW, CAC 155 is the PDF we have linked from the early network page. I
hadn't noticed before now, but seeing the missing page refreshes my
recollection.
Warner
7 p.m.
On Wed, Jan 22, 2020 at 10:54 AM Warner Losh <imp(a)bsdimp.com> wrote:
On Wed, Jan 22, 2020 at 7:59 AM Dan Cross <crossd(a)gmail.com> wrote:
Oopa, spoke one google search too soon. I found this:
"Sandy (A. G.) Fraser devised the Spider local-area ring (v6) and the
Datakit switch (v7) that have served in the lab for overadecade. Special
services on Spider included a central network file store, nfs, and a
communication package, ufs. Datakit, a ‘‘central office’’ for data
communication, gav e added impetus to research in distributed computing.
Fraser undertook the Unix Circuit Design System (see CDL in section 4.3) to
support his hardware projects"
in "A Research UNIX Reader: Annotated Excerpts from the Programmer’s
Manual, 1971-1986" by Doug Mcillroy.
Btw, the answer for #16 is `cagbef`: but `g` is
not an option. I would
think the answer would be `cafbde`. Apparently in the original, option
'(d)' is missing; one imagines that was to trick the unwary who failed to
adequately read the question.
I think this is wrong:
16. Q: Sort the following into chronological order: a) PWB 1.2, b) V7, c)
Whirlwind, d) System V, e) 4.2BSD, f) MERT.
A: cagbef
Whirlwind is a ringer.
So the MERT ACM paper is 1975. The BSTJ is July/Aug 1978 (received Feb
1978). Somewhere I read (don't have a handy reference for it) that MERT
ported V4 as a supervisor process which puts it in 1974 or so. In any
event, this predates everything except Whirlwind which I can't find a paper
for.
PWB 1.2 is based on V6 + stuff. PWB 1.0 was released 1977, but we don't
have an extant 1.2 tape to verify dates with, but 1978 wouldn't be
unreasonable.
We know 7th Edition was released Jan 1979 (PWB 2.0 was released, 1980
sometime)
System V was released January 1983
4.2BSD was released September 1983 (4.1c was released in 1982 though :)
So that would make the right answer c f a b d e
Even DMERT for the 3B20 was released in January 1983 (or the IEEE paper
for it was released then), so it can't be last.
I also have questions about this:
81. Q: What was the first Unix network?
A: spider
You thought it was Datakit, didn't you? But Sandy Fraser had an earlier
project.
When did Alexander G Fraser's spider cell network happen? For that matter,
when did Datakit happen? I can't find references to either start date on
line (nor anything on spider except for references to it in Dr Fraser's
bio). I can find references to Datakit in 1978 or so.
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).
Warner
> - Dan C.
>
>
> On Wed, Jan 22, 2020 at 4:32 AM Rob Pike <robpike(a)gmail.com> wrote:
>
>> The answers are up:
>>
>> https://commandcenter.blogspot.com/2020/01/unix-quiz-answers.html
>>
>> -rob
>>
>>
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days inactive
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12 comments
6 participants
participants (6)
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Adam Thornton -
Clem Cole -
Dan Cross -
Rob Pike -
Vincenzo Nicosia -
Warner Losh