COFF July 2023

coff@tuhs.org

19 participants
17 discussions

Requesting thoughts on extended regular expressions in grep.

by Grant Taylor

Hi, I'd like some thoughts ~> input on extended regular expressions used with grep, specifically GNU grep -e / egrep. What are the pros / cons to creating extended regular expressions like the following: ^\w{3} vs: ^(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec) Or: [ :[:digit:]]{11} vs: ( 1| 2| 3| 4| 5| 6| 7| 8| 9|10|11|12|13|14|15|16|17|18|19|20|21|22|23|24|25|26|27|28|29|30|31) (0|1|2)[[:digit:]]:(0|1|2|3|4|5)[[:digit:]]:(0|1|2|3|4|5)[[:digit:]] I'm currently eliding the 61st (60) second, the 32nd day, and dealing with February having fewer days for simplicity. For matching patterns like the following in log files? Mar 2 03:23:38 I'm working on organically training logcheck to match known good log entries. So I'm *DEEP* in the bowels of extended regular expressions (GNU egrep) that runs over all logs hourly. As such, I'm interested in making sure that my REs are both efficient and accurate or at least not WILDLY badly structured. The pedantic part of me wants to avoid wildcard type matches (\w), even if they are bounded (\w{3}), unless it truly is for unpredictable text. I'd appreciate any feedback and recommendations from people who have been using and / or optimizing (extended) regular expressions for longer than I have been using them. Thank you for your time and input. -- Grant. . . . unix || die

1 year, 9 months

Butler Lampson's 1973 Xerox PARC memo "Why Alto?"

by steve jenkin

What struck me reading this is the estimated price (~$10K) to build an Alto, elsewhere I’ve seen $12K and 80 built in the first run. [ a note elsewhere says $4,000 on 128KB of RAM. 4k-bit or 16-kbit chips? unsure ] I believe the first "PDP-11” bought by 127 at Bell Labs was ~$65k fully configured (Doug M could confirm or not), although the disk drive took some time to come. Later, that model was called PDP-11/20. Why the price difference? PARC was doing DIY - it’s parts only, not a commercial production run with wages, space, tooling & R+D costs and marketing/sales to be amortised, with a 80%+ Gross Margin required, as per DEC. Why didn’t Bell Labs build their own “Personal Computer” like PARC? They had the need, the vision, the knowledge & expertise. I’d suggest three reasons: - The Consent Decree. AT&T couldn’t get into the Computer Market, only able to build computers for internal use. They didn’t need GUI PC’s to run telephone exchanges. - Bell Labs management: they’d been burned by MULTICS and, rightly, refused the CSRC a PDP-10 in 1969. - Nobody ’needed’ to save money building another DIY low-performance device. A home-grown supercomputer maybe :) It’s an accident of history that PARC could’ve, but didn’t, port Unix to the Alto in 1974. By V7 in 1978, my guess it was too late because both sides had locked in ‘commercial’ positions and for PARC to rewrite code wasn’t justified: “If it ain’t Broke”… Porting Unix before 1974 was possible: PARC are sure to have had close contact with UC Berkeley and the hardware/software groups there. Then 10 years later both Apple and Microsoft re-invent Graphical computing using commodity VLSI cpu’s. Which was exactly the technology innovation path planned by Alan Kay in 1970: build today what’ll be cheap hardware in 10 years and figure out how to use it. Ironic that in 1994 there was the big Apple v Microsoft lawsuit over GUI’s & who owned what I.P. Xerox woke up up midway through and filed their own infringement suit, and lost. [ dismissed because approx they'd waited too long ] <https://en.wikipedia.org/wiki/Apple_Computer,_Inc._v._Microsoft_Corp.> ============== PDF: <http://bwl-website.s3-website.us-east-2.amazonaws.com/38a-WhyAlto/Acrobat.p…> Other formats: <http://bwl-website.s3-website.us-east-2.amazonaws.com/38a-WhyAlto/Abstract.…> ============== -- Steve Jenkin, IT Systems and Design 0412 786 915 (+61 412 786 915) PO Box 38, Kippax ACT 2615, AUSTRALIA mailto:sjenkin@canb.auug.org.au http://members.tip.net.au/~sjenkin

1 year, 9 months

Re: Butler Lampson's 1973 Xerox PARC memo "Why Alto?"

by jnc＠mercury.lcs.mit.edu

> From: steve jenkin > What struck me reading this is the estimated price (~$10K) to build an > .. [ a note elsewhere says $4,000 on 128KB of RAM. 4k-bit or 16-kbit > chips? unsure ] 16K (4116) - at least, in the Alto II I have images of. Maxc used 1103's (1K), but they were a few years before the Alto. > I believe the first "PDP-11" bought by 127 at Bell Labs was ~$65k fully > configured I got out my August 1971 -11/20 price sheet, and that sounds about right. The machine had "24K bytes of core memory .. and a disk with 1K blocks (512K bytes ... a single .5 MB disk .. every few hours' work by the typists meant pushing out more information onto DECtape, because of the very small disk." ("The Evolution of the Unix Time-sharing System"): 11,450 Basic machine CPU + 8KB memory 6,000 16KB memory (maybe 7,000, if MM11-F) 4,000 TC11 DECtape controller 4,700 TU56 DECtape transport 5,000 RF11 controller 9,000 RS11 drive 3,900 PC11 paper tape ------- 44,050 (Although Bell probably got a discount?) The machine later had an RK03: https://minnie.tuhs.org/cgi-bin/utree.pl?file=V1/u0.s but that wasn't there initially (they are 2.4MB, larger than the stated disk); it cost 5,900 (RK11 controller) + 9,000 (RK03 drive). Also, no signs of the KE11-A in the V1 code (1,900 when it eventually appeared). The machine had extra serial lines (on DC11's), but they weren't much; 750 per line. > Why the price difference? Memory was part of it. The -11/20 used core; $9,000 for the memory alone. Also, the machine was a generation older, the first DEC machine built out of IC's - all SSI. (It wasn't micro-coded; rather, a state machine. Cheap PROM and SRAM didn't exist yet.) Noel

1 year, 9 months

Bell System and the Video Game Industry?

by segaloco

So this evening I've been tinkering with a WECo 2500 I've been using for playing with telecom stuff, admiring the quality of the DTMF module, and it got me thinking, gee, this same craftsmanship would make for some very nice arcade buttons, which then further had me pondering on the breadth of the Bell System's capabilities and the unique needs of the video game industry in the early 80s. In many respects, the combination of Western Electric and Bell Laboratories could've been a hotbed of video game console and software development, what with WECo's capability to produce hardware such as coin slots, buttons, wiring harnesses for all sorts of equipment, etc. and then of course the software prowess of the Labs. Was there to anyone here's knowledge any serious consideration of this market by Bell? The famous story of UNIX's origins includes Space Travel, and from the very first manual, games of various kinds have accompanied UNIX wherever it goes. It seems that out of most companies, the Bell System would've been very well poised, what with their own CPU architecture and other fab operations, manufacturing and distribution chains, and so on. There's a looooot of R&D that companies such as Atari and Nintendo had to engage in that the Bell System had years if not decades of expertise in. Would anti-trust stuff have come into play in that regard? Bell couldn't compete in the computer market, and I suppose it would depend on the legal definitions applicable to video game hardware and software at the time. In any case, undercurrent here is the 2500 is a fine telephone, if the same minds behind some of this WECo hardware had gone into video gaming, I wonder how different things would've turned out. - Matt G.

1 year, 9 months

Advice sought: what to eventually do with my 1977 Lions Commentary?

by steve jenkin

I’ve no intention of selling these items and am definitely NOT disposing of them yet. No ‘offers’ please. In 1977, I took John’s “Operating Systems” course, and was one of 60-80 students who bought the first print run of the Commentary. I’m looking for suggestions of what to do with these three items pictured, some ideas of what to put in my will or donate before I go. Warren doesn’t need Yet Another Copy, he has some better copies already :) They aren’t in pristine condition and I made notes in both books, in pencil at least. The cover of the red book has slightly deteriorated. steve j PS: if the image is stripped by the list, a copy at: <http://members.tip.net.au/~sjenkin/SteveJ_Lions-Commentary.jpg> -- Steve Jenkin, IT Systems and Design 0412 786 915 (+61 412 786 915) PO Box 38, Kippax ACT 2615, AUSTRALIA mailto:sjenkin@canb.auug.org.au http://members.tip.net.au/~sjenkin

1 year, 9 months

IBM SLT Module Identity?

by segaloco

Hello, today I have received an IBM binder from 1974 pertaining to IBM Skylab activities as well as a small IBM SLT, single wide, with four modules on it. Two of the modules are labeled: 361456 IBM WF 1 03S 215 And the other two are: 361453 IBM 22 1-009 415 From what I could find online, there is a close SLT card with 4 of the 361453's instead of 2, but that doesn't help much. That board is listed as 00211 in the reference this info is from[1]. Faintly on the connector I can make out: 00008 A 0 204 YM It is very, very faint in places though so that may not be correct. The specific little blocks on the board appear to show up on others, so nothing unheard of, although I wouldn't know where to start on identifying what this does precisely, all I can find are cursory references in a few places to the numbers on the chips re: SLT modules. - Matt G. [1] - https://ibm-slt-reference.fandom.com/wiki/SLT_Board_List (why is this a fandom.com wiki...) P.S. If you or a loved one are in possession of IBM mainframe hardware that would benefit from this SLT board, happy to send it to you, I probably won't do much with it unless I can figure out the pinout and do weird things over GPIO pins from one of my single boards.

1 year, 9 months

A slack clone in 5 lines of bash

by Edouard Klein

Dear Old Farts, I've written a chat system that relies at its core on UNIX's permission system. All the explanations are here: https://the-dam.org/docs/explanations/suc.html I thought it would be of interest to the list as it has one foot in the past (using system primitives from the 70's for access control) and one foot in the future: (optionally) using GNU Guix's declarative configuration to create the necessary users, groups, and files. I know most of you have used (and some maybe still do) talk et al. This system is even simpler, just a forever loop: while /usr/bin/true do read -r line || exit 0 # EOF /usr/bin/echo "$(/usr/bin/date --iso-8601=seconds)"\ "$(printf "%-9s" "$(/usr/bin/id --user --name --real)")" \ "$line" >> /var/lib/suc/"$1" done I'd be happy to hear any comments or to welcome you on the Dam, where we test this stuff. Cheers ! Edouard.

1 year, 9 months

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COFF July 2023