TUHS

tuhs@tuhs.org

17 participants
6470 discussions

by jnc＠mercury.lcs.mit.edu

> From: Steve Nickolas > there's no easy way to do preemptive multitasking without extra > hardware. Perhaps you're using some idiosyncratic definition of "preemptive" and "multitasking", but to me that statement's not accurate. Let's take the "multitasking" part first: that just means 'two or more computations can run at the same time, sharing the machine' - and that's not hard to do, without special hardware, provided there's some way (in the organization of the software) to save the state of one when the other is running. Many simple systems do this; e.g. the MOS system that I used on LSI-11's, BITD. "Preemptive" is a bit trickier, because things have to be organized so that one 'task' can be temporarily stopped arbitrarily (i.e. without it explicitly giving up the processor, which is what e.g.MOS did) to let another run. There does need to be some asynchronous way of inciting the second 'task' to run, but interrupts (either clock, or device) do that, and pretty much every machine has those. MINI-UNIX, for example, has premptive multitasking. The thing that takes special hardware is _protecting_ one task from a bug in another - a bug which could trash the first tasks's (or the system's!) memory. One has to have memory management of some kind to do that. > From: Dave Horsfall > I would start with something like Mini-Unix MINI-UNIX would be a good place to start if one wanted to bring up a system on a machine without memory management; there's nothing in the kernel which is PDP-11 dependent that I can think of (unlike V6, which had a fairly heavy dependency on the PDP-11 memory management hardware - although one could of course rip that all out, as MINI-UNIX did). However, one's still looking at a fair amount of work, both to get rid of any traces of PDP-11isms (e.g. stack growth direction), and translate the assembler part (startup, and access to non-C operations). Something like FUZIX might be an easier option. Noel

4 years, 4 months

Why do compress(1) and pack(1) use the .Z / .z extension?

by Hans Wennborg

I'm trying to find out why compress(1) uses .Z as filename extension. My theory is that it was inspired by pack(1), which uses the .z extension. However, I haven't been able to find any info on why pack(1) uses that extension. Does anyone here know? Some searching led me to [1] which is a man page for pack from AUSAM. It's written by Steve Zucker in 1975, so perhaps the extension is z for Zucker? Was Zucker's pack(1) the first, though? This message [2] talks about a Bell version. Does anyone here have any information about this? Cheers, Hans 1. https://minnie.tuhs.org/cgi-bin/utree.pl?file=AUSAM/doc/man/man1/pack.1 2. https://tech-insider.org/unix/research/1984/0319.html

4 years, 4 months

W. Richard Stevens wife's email?

by Larry McVoy

I was making coffee into the cup I've had for decades that talks about his networking books. I realized I might have something that would help his wife a bit. I had her email but long since lost it. Anyone have it? --lm

4 years, 4 months

Re: [TUHS] free dead trees, to the best possible home

by Rich Morin

Back in mid-January, I posted a note saying: > TL; DR. I'm trying to find the best possible home for some dead trees. ... A lot (far too much, IMNSHO!) has happened since then. In any case, I thought folks here might appreciate an update. In brief, Iain Maoileoin offered to pay for shipping a largely unknown amount of technical (mostly computer-related) books to his repurposed missile sile (!) near Inverness, Scotland. Early this Fall, I packed up 16 cardboard boxes (designated 0-F, of course :-) and the shippers hauled them off. Dunno when they'll arrive, let alone in what condition, but trying to save them from recycling seemed worth the effort. FYI, the total weight was a bit over a ton. Meanwhile, my spouse and I gave away and/or packed up the rest of our things and drove ourselves and five cats up to Seattle, WA, USA. Somewhere in a shipping container, there is still a cubic foot or so of historical Unix papers from Jim Joyce; when it surfaces, I'll post again about rehoming it. -r

4 years, 5 months

516-TSS documents

by Jon Steinhart

Well, it's a very rainy day and since COVID is keeping me home I just fed my 516-TSS notebooks into the scanner. It's about 17MB of stuff. Not sure what to do with it since I don't have a place to serve it and since they're scanned images they're too big to post. Here's the list of documents; email me if you're wanting something in a hurry while the archive stuff is figured out. Note that the smell of mildew wasn't preserved in the scanning process. 516-1-516-DOCUMENTATION.pdf 516-3-DDP-516-PRICE-LIST.pdf 516-4-Disk-Layout.pdf 516-5-System-Table-Formats.pdf 516-6-Segment-Format.pdf 516-8-Disk-Hole-Format.pdf 516-7-DMA-Mnemonics.pdf 516-9-Addresses.pdf 516-10-11-12-Ring-Formats.pdf 516-12-Specifications-For-The-Node-Modem-Interface.pdf 516-13-Trac-Character-Strings.pdf 516-14-GMAP-Assembler-for-the-Multi-Programmed-516.pdf 516-15-A-Suggested-Graphic-Display-with-Keyboard-for-Graphic-Terminals.pdf 516-16-516-Assembler-And-Post-Processor-For-Unsegmented-Programs.pdf 516-18-Format-For-Ring-Interrupt.pdf 516-19-Thread-Save-Blocks.pdf 516-20-Card-Reader-Bootstrap-and-Programs.pdf 516-21-Octal-Package.pdf 516-22-A-Repeater-For-The-Node-Modem.pdf 516-23-CLEAR-CORE-CARD.pdf 516-24-SOROBAN-CARD-READER-TEST-PROGRAM.pdf 516-25-IO-Table.pdf 516-26-Disk-DMA-Queue.pdf 516-27-GE-Disc-Files-For-516-Programming.pdf 516-27-Thread-Table.pdf 516-28-IO-Ring_Device-Codes.pdf 516-29-Five-Bit-Character-Codes.pdf 516-30-Text-Editor.pdf 516-31-Relocatable-Segment-Octal-Package.pdf 516-32-ASCII-Character-Mnemonics.pdf 516-34-Display-List-For-Glance.pdf 516-35-Internal-Megacycle-Clock.pdf 516-36-Node-Modem-Interface-For-Computer-Terminals.pdf 516-38-P8SYS.pdf 516-39-Resource-Monitor-Meters.pdf 516-40-SNAP-Time-Sharing-Calculator.pdf 516-41-516-Segment-Assembler.pdf 516-42-Memory-Service-Unit-Format.pdf 516-43-GEBKUP-and-FLOAD.pdf 516-44-FSNAP-Floating-Point-Time-Sharing-Calculator.pdf 516-45-516-316-Assembler-and-Binder.pdf 516-46-CALC-A-Desk-Calculator-Program.pdf 516-47-Remote-Data-Plotting.pdf 516-48-CODING-FOR-GLANCE-G-Graphics.pdf 516-49-516-Segment-Assembler.pdf 516-50-Use-Of-The-516-Segment-Assemblers-Macros-In-Application-Programs.pdf 516-51-FSNAP-Designers-Guide.pdf 516-51-FSNAP-Users-Guide.pdf 516-52-DESK-A-Desk-Calculator.pdf 516-53-FSEOF-Flag-End-Of-File.pdf 516-54-Context-Editing.pdf 516-55-One-Card-Core-Save-Program.pdf 516-56-PRIME-An-Integer-Factoring-Program.pdf 516-57-Format-For-The-516-Node-T-I-U-Spider-Interface.pdf 516-59-Calling-Procedures-For-Math-Routines.pdf 516-59-INITIALIZATION-OF-THE-516-TSS-SYSTEM.pdf 516-60-SORT-SUBR-FOR-SEGMENTED-PROGRAMS.pdf 516-61-516-TSS-SYSTEM-BOLTED-IN-CORE-SUBROUTINES.pdf 516-63-Display-Controller-Glance-G.pdf 516-65-SOME-DIGITAL-FILTER-APPLICATION-PROGRAMS.pdf 516-66-TSS-516-GE-Communication.pdf 516-67-Node-Format-For-PDP-11.pdf 516-68-DFILE-N-A-Program-for-TSS-516.pdf 516-69-GLANCE-G-COMMUNICATION-FORMAT-TSS-516-TO-SCOPE.pdf 516-70-Routines-to-Perform-Character-String-IO-in-a-FSNAP-Program.pdf 516-71-FSNAP-Debugging-Aids.pdf 516-72-Node-Test.pdf 516-73-Node-IO-Software.pdf 516-75-Display-Text-Editor-DTE.pdf 516-76-LOCAL-DATA-PLOTTING.pdf 516-77-GLANCE-PLOTTING-ROUTINES-GPLOT-GLANCE-CHRGEN.pdf 516-77-V2-GLANCE-PLOTTING-ROUTINES-GPLOT-GLANCE-CHRGEN.pdf 516-78-DUMP.pdf 516-79-New-File-Features-in-FSNAP.pdf 516-81-OPTION-CHANGING-IN-GPLOT.pdf 516-86-MODIFICATIONS-TO-201-DATAPHONE-SOFTWARE.pdf DDP-516-PROGRAMMERS-REFERENCE-CARD.pdf DDP-516-Instruction-Set-Summary.pdf Index.pdf README

4 years, 5 months

Re: [TUHS] Seeking wisdom from Unix Greybeards

by jnc＠mercury.lcs.mit.edu

> From: "Theodore Y. Ts'o" > was there anything that had similar functionality which pre-dated Bill > Joy and termcap in late 70's? Is your question purely in Unix, or more general? If the latter, there's the terminal-independent support of video terminals in ITS; that dates to the mid-1970's (i.e. circa V5 or so). User programs output device-independent display control codes (I have this memory that they were called P-Codes, but that could be my memory failing), and the OS translated them to the appropriate screen-control characters. One additional hack was that the number of terminal types supported in the OS was limited; there was however a protocol called SUPDUP which sent (basically) those device-independent codes over a remote login (originally over NCP) frm the server machine to the client. The User SUPDUP client supported a lot more terminal types; so people with odd-ball terminals used to log in, SUPDUP _back_ to their machine, and away they went. Noel

4 years, 5 months

Package Management

by Henry Bent

Hello All, I know I have asked this before, but I am curious about any new replies or insight. How did package management start? Were sites keeping track of packages installed in a flat file that you could grep (as god intended) somewhere, or were upgrades and additions simply done without significant announcement? At what point did someone decide, 'Hey, we need to have a central way to track additional software"? I know of DEC's setld and SGI's inst in the latter half of the '80s. What was the mechanism before that? -Henry

4 years, 5 months

Re: [TUHS] 516-TSS Documents

by jnc＠mercury.lcs.mit.edu

> On Mon, Nov 23, 2020 at 12:28 PM Erik E. Fair <fair-tuhs(a)netbsd.org> wrote: > The Honeywell DDP-516 was the computer (running specialized software > written by Bolt, Bernanek & Newman (BBN)) which was the initial model of > the ARPANET Interface Message Processors (IMP). The IMPs had a lot of custom interface hardware; sui generis serial interlocked host interfaces (so-called 1822), and also the high-speed modem interfaces. I think there was also a watchdog time, IIRC (this is all from memory, but the ARPANET papers from JCC cover it all). Noel

4 years, 5 months

516-TSS Documents

by Jon Steinhart

These are in Warren's hands now and he'll let us know where their permanent home ends up being. Since these are pretty much uncirculated unlike the UNIX documents I wrote a README to go along with them which Heinz reviewed so it's the best that two aging sets of memories can do. Here it is: - - - 516-TSS is a little-known but groundbreaking and influential operating system that was developed at Bell Telephone Laboratories. I came across this system because Carl Christensen and later Heinz Lycklama were major contributors to it, and they were also advisors for the Bell Labs Explorer Scout Post at Murray Hill. I was a member of that post which allowed us to play with computers on Monday evenings, and 516-TSS was what most of us used. Through a series of amazingly lucky events, I ended up working as a summer student for Carl and Heinz and got to contribute to the system. Long before the term "code spelunking" was coined Carl and Heinz taught us both code and spelunking. This is not a complete set of 516-TSS documents, it's a couple of notebooks that I found in a box in the basement. Probably my ancient work-at-home copy. I don't know enough history to know if it was the first, but 516-TSS was an early department-level time-sharing system. It was built around a Honeywell DDP-516. While other time-sharing systems predate 516-TSS, they weren't systems that one's department could afford. CTSS certainly came earlier, but it used a monster IBM 7090 mainframe. In round numbers, a 7090 cost $3,000,000 dollars, a DDP-516 cost $50,000. 516-TSS was also a virtual memory system; again not the first but a rarity in that era. My recollection is that it used the 516's index register as the base address register, and there was some complicated mucking around that a program had to do if it needed to use the index register including disabling interrupts and eventually restoring the register from .PRESB (present base address), one of those weird things stuck in my memory from long ago. I believe that the system's development predated UNIX although I remember our department getting a PDP-11/45 running UNIX Version 3 in the summer of 1973. This machine was acquired so that Doug Bayer and Heinz Lycklama could develop the MERT operating system. The 516 was a testbed for a lot of novel technologies. It had a local area network called the ring which was later made to work on PDP-11s including Ken and Dennis's machine up in the attic of building 2. It was also used to develop the GLANCE graphics terminals. My recollection is that one of the main drivers behind getting the ring to work on PDP-11s and UNIX was so that Ken could get a GLANCE-G terminal for playing chess. Sandy Fraser's Spider network was developed there. It supported a number of novel applications including Dick Hause's DTE graphics editor; way ahead of its time. I remember that one GLANCE terminal was fitted with an array of LEDs and photodiodes to make an early version of a touch screen. While it wasn't exactly work related, a number of the people in the department had purchased property up in Vermont for ski cabins. An important use of the 516-TSS system and GLANCE-G terminals was to figure out survey closures. The property surveys were ancient, of the "from the big rock to the left of the tree that's no longer there" sorts of things, so figuring out the actual property lines was an interesting problem. The 516 also had a wide area network which consisted of picking up the phone and calling the computer center. It had a monster GE-635 or maybe 645 left over from the Multics project. It may have been renamed to be a Honeywell 6070 with Honeywell's acquisition of GE's computer business. The computer center kept department costs down by hoarding all of the really expensive peripherals. For example, we didn't have a card punch; that was effectively done via remote job entry. We didn't have a graphics printer either, so when I was working on GPLOT I'd submit remote jobs to the computer center for printing. Matter of fact, I don't think that we even had a printer in our department; we sent stuff up to the computer center for printing. Although, in those days many terminals used paper. The 516 console was an ASR-33. There was also the ability to send jobs to the computer center and have it call back with results. This early approach to a WAN showed up as the tss command in UNIX. One of the missions of the department was the development of an all-digital telephone exchange which is why some of the documents describe programs that assist with digital filter design. Both Jim Kaiser and Hal Alles were in the department. One of the side-effects of all this was Hal figuring out how to use the filter hardware connected to a LSI-11/03 to make sound, followed by Dave Hagelbarger building a very interesting keyboard for it, culminating in a visit by Stevie Wonder trailed by a large number of screaming secretaries. No sexism intended, it was a different world back then. The LSI-11 was one of the motivations for Heinz to create the LSX operating system. My recollection is that on Dave's keyboard each key was an antenna, and that there was strip of ribbon cable underneath where each wire was driven by a different bit on a binary counter. This allowed the position of each key to be determined which I think was way ahead of its time. I don't think that any commercially available keyboards did this at the time, they were all just on/off. Dave also designed the GLANCE keyboard which spoiled me for life. I don't remember how he did it, but the keys had a really good feel where once they got pushed past a certain point they snapped down. I do recall that there was a small solenoid mounted on the circuit board so that the keys gave a satisfying click that you could feel in your fingers. Another of Dave's gizmos was the chess board that he made for Ken. My recollection is that there was a tuned circuit in the base of each chess piece and an antenna grid in the board so that the PDP-11 could read the position of each piece. Some of the success of the 516 system was that other departments used it. I spent some time working an a 516-based integrated circuit test system where the test equipment stations were on the ring. Seems really dumb now, it's hard to believe that there was a time in which a computer cost more than a wafer stepper. In addition to his work on 516-TSS, Carl Christensen was one of the people who interviewed Ken Thompson for a job at the labs and gave a thumbs up. The 516-TSS documents don't have author names, just initials. Here's who they are to the best of my recollection. ADH Dick Hause CC Carl Christensen DJB Doug Bayer DRW Dave Weller EPR ? HL Heinz Lycklama JCS John Schwartzwelder JES Jon Steinhart JFK Jim Kaiser JHC Joe Condon JVC John Camlet LIS ? MAS ? RFG Rudy Garcia There is one mysterious document in the collection about a "memory service unit". I had this filed under "zapper". To the best of my recollection it was the PROM programmer that we used to burn the microcode PROMs for the GLANCE terminals. Jon Steinhart, 11/20/2020

4 years, 5 months

UNIX NEWS and ; login: archives, particularly from 1975-1978

by John Gilmore

While cleaning up a few shelves of old USENIX proceedings, I found a mysterious manila envelope full of xeroxed copies of all the original UNIX NEWS newsletters from 1975 thru 1977. It was renamed to ;login: in 1977 and has continued publication to this day. The envelope also contained ;login: issues v2n6 thru v3n8 (1977-1978). I scanned those all in today and put them up on my website, here: http://www.toad.com/early-usenix-newsletters/ These have not been OCR'd, and many of the pages were rotated by 90 degrees in the original publication, to fit two pages of typewritten correspondence (or recipient address lists) into one page of newsletter. Still, in a quick web search I was unable to find copies of these anywhere else, so I invested a few hours to scan them in and post them for historical interest. As an example, Sixth Edition (v6) UNIX was announced in issue number 1. These are all free to publish nowadays. USENIX was one of the first technical organizations to establish an Open Access policy for its publications, a step which distinguishes them from ACM and many academic publishers who favor revenue for themselves over the progress of science. (I voted for this policy decades ago when I was a USENIX board member.) This page, for example, says: https://www.usenix.org/conference/usenixsecurity20/presentation/schwarz "USENIX is committed to Open Access to the research presented at our events. Papers and proceedings are freely available to everyone once the event begins. Any video, audio, and/or slides that are posted after the event are also free and open to everyone." The ;login: archives at USENIX.org are complete from October 1997 to today: https://www.usenix.org/publications/login Also, most but not all issues of ;login: from 1983 to 1997 have been scanned by USENIX and uploaded to the Internet Archive here: https://archive.org/details/usenix-login?&sort=date The USENIX Association apparently has paper copies of the stuff I scanned in today, but they are still trying to locate ;login: issues from 1979 and parts of 1980 and 1981. In addition, they are backlogged on scanning in their old materials (including copies of ;login: between 1978/09 and 1983/02). If you have old copies of ;login: that you don't see visible in these places, please scan them, or offer them to USENIX. Also, if you have old proceedings of USENIX conferences, there are still three that the USENIX staff do not have any copy of: XFree86 Technical Conference https://www.usenix.org/legacy/publications/library/proceedings/xfree86/ 2001-11-08 5th Annual Linux Showcase & Conference https://www.usenix.org/legacy/publications/library/proceedings/als01/tech.h… 2001-11-08 WORLDS '04 https://www.usenix.org/legacy/events/worlds04/tech/ 2004-12-05 If you have any of these three, please let <info(a)usenix.org> know. They also lack about twenty more for which they have posted the academic papers, but don't have the covers or front-matter, so if you have other proceedings from between 1989 and 2004 that you'd be willing to part with or scan, also let them know. Thanks! John

4 years, 5 months

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TUHS