TUHS

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6541 discussions

I've just come across some old Unix Sources

by David Barto

Notably: 32v_usr.tar.gz and sys3.tar.gz. I’ve not unpacked the tar files. If someone would like more detail about the contents I’ll produce a TOC offline for them. David

2 years, 5 months

Earliest UNIX Workstations?

by Paul Ruizendaal

As a result of the recent discussion on this list I’m trying to understand the timeline of graphical computing on Unix, first of all in my preferred time slot ’75 -’85. When it comes to Bell Labs I’m aware of the following: - around 1975 the Labs worked on the Glance-G vector graphics terminal. This was TSS-516 based with no Unix overlap I think. - around the same time the Labs seem to have used the 1973 Dec VT11 vector graphics terminal; at least the surviving LSX Unix source has a driver for it - in 1976 there was the Terak 8510; this ran primarily USCD pascal, but it also ran LSX and/or MX (but maybe only much later) - then it seems to jump 1981 and to the Blit. - in 1984 there was MGR that was done at Bellcore Outside of the labs (but on Unix), I have: - I am not sure what graphics software ran on the SUN-1, but it must have been something - Clem just mentioned the 1981 Tektronix Magnolia system - Wikipedia says that X1 was 1984 and X11 was 1987; I’m not sure when it became Unix centered - Sun’s NeWS arrived only in 1989, I think? Outside of Unix, in the microcomputer world there was a lot of cheap(er) graphics hardware. Lot’s of stuff at 256 x 192 resolution, but up to 512 x 512 at the higher end. John Walker writes that the breakout product for Autodesk was Interact (the precursor to AutoCAD). Initially developed for S-100 bus systems it quickly moved to the PC. There was a lot of demand for CAD at a 5K price point that did not exist at a 50K price point.

2 years, 5 months

Re: Setting up an X Development Environment for Mac OS

by jnc＠mercury.lcs.mit.edu

> From: Lars Brinkhoff > It's my understanding it was started by Bob Scheifler of the CLU group. Yes, that's correct. (Bob's office was right around the corner from me - although I had very little knowledge of what his group was up to; I was too busy with other things.) I have this vague memory that his version was actually written in CLU? Can that be correct? It would make sense, since that group was so focused on CLU - but maybe not, see below. X must have been done after LCS got the 750 farm (on which we ran 4.1c, to start with) - although I don't know what kind of terminals they were using to run X on - we didn't have any bit-mapped displays on them, I'm pretty sure. Although maybe it was later, once Micro-Vaxes appeared? I have this vague memory that it was based (perhaps only in design, not code re-use) on a window system done at Stanford {looks}; yes, W (hence 'X'): https://en.wikipedia.org/wiki/W_Window_System The X paper listed there: https://dl.acm.org/doi/pdf/10.1145/22949.24053 doesn't say anything about the implementation, so maybe that vague memory/assumption that I had that it was originally written in CLU is wrong. Liskov's 'History of CLU' paper, which lists things done in CLU, doesn't mention it, so I must have been confused? Do any of the really early versions of X (and W) still exist? Noel

2 years, 5 months

[off-topic] Anyone still using USENET?

by arnold＠skeeve.com

Hi. I've been using trn for decades to read a very few USENET groups. Until recently I've been using aioe.org as my NNTP server but it seems to have gone dark. Before that I used eternal-september.org, but when I try that I now get: | $ NNTPSERVER=news.eternal-september.org trn | Connecting to news.eternal-september.org...Done. | | Invalid (bogus) newsgroup found: comp.sys.3b1 | | Invalid (bogus) newsgroup found: comp.sources.bugs | | Invalid (bogus) newsgroup found: comp.misc | | Invalid (bogus) newsgroup found: comp.compilers | .... And those all are (or were!) valid groups. If anyone has suggestions for a good free NNTP server, please let me know. Privately is fine. I'm at a bit of a loss otherwise. Thanks, Arnold

2 years, 5 months

reading historic magnetic tapes

by Steve Simon

i worked for some years on video and film archive restoration. baking old, badly stored magnetic tapes prior to reading them is a common practice. my favourite was a story of a rock band (i think the stones) who wanted to play an old 24 track master tape but discovered it seemed to be stuck together. there is a nasty affliction of mag tapes called sticky vinegar syndrome, so they did the right thing and sent a section of tape for analysis. the results came back: the tape had suffered impregnation with “vodka and coke”. some things never change. -Steve

2 years, 5 months

tesseract has gotten so much better

by Will Senn

Hi All, I just wanted to let y'all know that tesseract ocr has significantly improved and is much easier to use that it used to be. I have been using it with my workflow for a bit and it's crazy how much better it is than it was back when I tried it last (admittedly 5-6 years ago). For those of you doing your own scans, or those of you finding sad little pdfs without ocr, the process is fairly simple. Let's say you find "The Master Manual of Fortran.pdf" out there in the wild (or scan it). Here's how to turn it into a glorious ocr'd version: Export your pdf as a multi-image tiff - it'll be ginormous, but you can delete it later (on Mac, this is just export from preview and select tiff, but gs will do it to, if I remember correctly) and then: tesseract The\ Master\ Manual\ of\ Fortran.tiff out -l eng PDF et voila, I nice, if large pdf, called out.pdf or somesuch will appear with ocr text that actually matches your scan (it seems to have caught up to adobe's ocr, or is quite close in my view, ymmv). I speak English, so I installed tesseract and tesseract-eng, but it supports a bunch of other languages if you need them. Apparently google's been supporting and developing it for while now and if my results are any indicator, it's paying off (boy do I remember all the gobbledegook it used to produce). tesseract will import from different image types, multiple images, etc. I just like the simplicity of tiff->pdf. Anyhow, thought y'all might like to know as many of you live off the scans :). Will

2 years, 5 months

C port of Ken Thompson's Space Travel

by Lars Brinkhoff

If you don't want to play Space Travel on PDP-7 Unix, you can now do it more easily running this C port. The controls are--so far--just as quirky as the original. https://github.com/mohd-akram/st

2 years, 5 months

Re: Earliest UNIX Workstations?

by John Foust

At 01:20 AM 1/26/2023, John Cowan wrote: >WP says the Terak 8510/a was the first graphical workstation; it came out in 1976-77 and ran the UCSD p-System.Â I had never heard of it before. I have a dozen or so Teraks (a PDP-11/03 based system) as well as many floppies and other inherited items and notebooks from one of the Terak founders. This may seem like a lot but there's another guy who might still have a larger collection. Mini-Unix is described here: http://www.tavi.co.uk/unixhistory/mini-unix.html Sixth edition, no MMU. The Bell memo there is dated January 1977. There was a Mini-Unix for the Terak described here in May 1979 but I don't think I have a copy. See page 14... https://conservancy.umn.edu/bitstream/handle/11299/159028/UCC_Special%20_Is… Terak floppies are described here: http://www.60bits.net/msu/mycomp/terak/termedia.htm A memo there says they got their copy in April 1980. There's no indication that this Mini-Unix can *use* the Terak's mono bitmapped display, short of writing your own routines. Pinning "first" on computers is always a tricky process. - John

2 years, 5 months

Re: Earliest UNIX Workstations?

by Paul Ruizendaal

>> * What do I really mean by workstation? Ex.gr. If an installation had a >> PDP-11 with a single terminal and operator, is it not a workstation? Is >> it the integration of display into the system that differentiates? > > I remember people calling something a workstation, > if it has the four "M" > > at least 1 MByte memory > at least 1 megapixel display > at least 1 mbit/s network > can't remember the fourth(was there a fourth?) I remember it as: at least 1 MByte memory at least 1 megapixel display at least 1 MIPS cost at most 1 mega penny (10K, maybe 35K in today’s money) That matches with Wikipedia, for whatever that is worth: https://en.wikipedia.org/wiki/3M_computer but note that it talks about 3M not 4M. With hindsight, not adding in networking speed looks strange -- but maybe the world had already settled on LAN speeds above 1Mb/s by 1980 (Ethernet, ARCNet)

2 years, 5 months

Fwd: How did Bell Labs start to work on Project MAC?

by Dan Cross

[Bcc: to TUHS as it's not strictly Unix related, but relevant to the pre-history] This came from USENET, specifically, alt.os.multics. Since it's unlikely anyone in a position to answer is going to see it there, I'm reposting here: From Acceptable Name <metta.crawler(a)gmail.com>: >Did Bell Labs approach MIT or was it the other way around? >Did participating in Project MAC come from researchers requesting >management at Bell Labs/MIT or did management make the >decision due to dealing with other managers in each of the two >organizations? Did it grow out of an informal arrangement into >a format one?" These are interesting questions. Perhaps Doug may be in the know? - Dan C.

2 years, 5 months

Release 5.0 Vs. System V

by segaloco

Good morning all, currently trying to sort out one matter that still bewilders me with this documentation I'm working on scanning. So I've got two copies of the "Release 5.0" User's Manual and one copy of the "System V" User's Manual. I haven't identified the exact differences, lots of pages...but they certainly are not identical, there are at least a few commands in one and not the other. Given this, and past discussion, it's obvious Release 5.0 is the internal UNIX version that became System V, but what I'm curious about is if it was ever released publicly as "Release 5.0" before being branded as System V or if the name was System V from the moment the first commercial license was issued. The reason I wonder this is some inconsistencies in the documentation I see out there. So both of my Release 5.0 User's Manuals have the Bell logo on the front and no mention of the court order to cease using it. Likewise, all but one of the System V related documents I received recently contain a Bell logo on the cover next to Western Electric save for the Opeartor's Guide which curiously doesn't exhibit the front page divestiture message that other documents missing the Bell logo include. Furthermore, the actual cover sheet says "Operator's Guide UNIX System Release 5.0" so technically not System V. In fact, only the User's Manual, Administrator's Manual, Error Message Manual, Transition Aids, and Release Description specifically say System V, all the rest don't have a version listed but some list Release 5.0 on their title page. Furthering that discrepancy is this which I just purchased: https://www.ebay.com/itm/314135813726?_trkparms=amclksrc%3DITM%26aid%3D1110… Link lives as of this sending, but contains a closed auction for an Error Message Manual from the "Release 5.0" documentation line but no Bell logo. Until the Operator's Guide and this auction link, I haven't seen any "Release 5.0" branded stuff without a Bell logo, and before I bought the System V gold set, I hadn't seen System V branded stuff *with* the Bell logo. This shatters an assumption that I had made that at the same time the documentation branding shifted to System V was the same time the removal of the Bell logo happened, given that divestiture was what allowed them to aggressively market System V, but now this presents four distinct sets of System V gold documentation: Release 5.0 w/ Bell logo Release 5.0 w/o Bell logo System V w/ Bell logo System V w/o Bell logo I'm curious if anyone would happen to know what the significance here is. The covers are all printed, I can't see any indication that a bunch of 5.0 manuals were retroactively painted over nor that any System V manuals got stamped with a Bell post-production. What this means is "Release 5.0" documentation was being shipped post-divestiture and "System V" was being shipped pre-divestiture. If Release 5.0 was publicly sold as System V, then what explains the post-divestiture 5.0 manuals floating around in the wild, and vice versa, if USG couldn't effectively market and support UNIX until the divestiture, how is it so many "Release 5.0" documents are floating around in well produced commercial-quality binding, both pre and post-divestiture by the time the name "System V" would've been king. Were they still maintaining an internal 5.x branch past System V that warranted its own distinct documentation set even into the commercial period? This period right around '82-'83 is incredibly fascinating and I feel very under-documented. - Matt G.

2 years, 5 months

Three New Scans (Sys V User and Admin Guides, TS 4.0 Programmer's Package)

by segaloco

Good day everyone, just emailing to notify of three more documents I've uploaded to archive.org since my last slew of them: https://archive.org/details/unix-programming-starter-package - Up first is the UNIX Programming Starter Package. This is one of a pair of manuals that saw publication in the Bell system around the time of UNIX/TS 4.0. The documents here appear to be a subset of those which shipped with Documents for UNIX 4.0. Nothing particularly new here. There is a companion manual, UNIX Text Editing & Phototypesetting Starter Package, which I also have but haven't hit the scan bench with yet. Like this one, that is just a subset of papers from the Documents for UNIX collection. Based on the TOC, this second one also shipped with one of those PWB/MM multi-fold pamphlets, but didn't receive one when I got this. Luckily that was also scanned as part of the 4.0 collection. So nothing really new here, save that these are 1st generation scans vs the scans of photocopies for the 4.0 release. That said, I've seen this set with the same cover motif except with an AT&T death star logo in the upper right. Didn't look into it too much at the time, but I'd be curious if anyone might have those and if they have the programming one, if it still refers to Release 4.0 in the documentation roadmap. https://archive.org/details/unix-system-users-guide-release-5-0 - This is the User's Guide that shipped with Release 5.0/System V. This covers the usual suspects as well as some notes on RJE and SCCS from a user's perspective. https://archive.org/details/unix-system-administrators-guide-5-0 - And this is the Administrator's Guide likewise from SysV era. This one contains setup and maintenance notes for both DEC (PDP & VAX) and 3B20(S) machines, as well as papers on accounting, LP printing, RJE, filesystem checking, and the System Activity Package. Additionally, the guide includes the original Modification Request form. - Matt G.

2 years, 5 months

interesting case of not getting the point: dc on a mac

by ron minnich

dc >>> it prompts with '>>> ' wonder where that came from? First time I've seen it. Seems to have a certain lack of understanding attached to it.

2 years, 5 months

v8 shell

by Rob Pike

Found this tweetstream, here folded together, when looking for something else (now lost) in my twitter archive: ========== Things I miss from the v8 shell. 1) All shell output was valid shell input. 2) Typing dir/cmd would find the command $PATH/dir/cmd. Subdirectories of your bin, in other words. 3) Functions were exportable. For one brief shining POSIX meeting, that was true in POSIX too but then... 4) The implementation was lovely and easy to understand. (No, it wasn't shalgol. Bourne fixed that for us.) 5) That I could learn things from it, like how to write a recursive descent parser.* 6) It ran in cooked mode. As expected, all that work making it a great shell is lost to history. https://t.co/IzApAUSmzN is silent. Well, the code is released now. ========== -rob * elegantly.

2 years, 5 months

AIX moved into maintainance mode

by arnold＠skeeve.com

https://www.theregister.com/2023/01/17/unix_is_dead/ FYI. Arnold

2 years, 5 months

The death of general purpose computers -> COFF

by Warren Toomey

Hi all, can we move "The death of general purpose computers" to COFF now as it's not directly relevant to Unix. Thanks, Warren

2 years, 5 months

Managers/architects (was: AIX moved into maintainance mode)

by jnc＠mercury.lcs.mit.edu

> From: Larry McVoy <lm(a)mcvoy.com> > At least 30 years ago I said "He's good programmer, a good architect, > and a good manager. I've never seen that in one person before". Corby? Although he was just down the hall from me, I never saw him operating in any of those roles; maybe some of the old-time Unix people have some insight. Saltzer is about off-scale in #2; probably good as a manager (although I had a monumental blow-up with him in the hallway on the 5th floor, but I was pretty close to unmanageable when I was young ;-); he took over Athena when it was stumbling, and got it going. Dave Clark is high on all three - he could manage me! :-) Bob Taylor? PARC did some _incredibly_ important stuff in his time. Yes, I know a lot of the credit goes to those under him (Butler Lampson, Alan Kay - not sure if he was in Taylor's group, Boggs, Metcalfe, etc) but he had to manage them all. Not sure what his technical role was, though. Vint Cerf? Again, A1*** as a manager, but had some failings as a architect. I think the biggest share of the blame for the decision to remove the variable size addresses from TCP/IP3, and replace them with 32-bit addresses in TCP/IPv4, goes to him. (Alas, I was down the hall, not in the room, that day; I wasn't allowed in until the _next_ meeting. I like to think that if I'd been there, I could/would have pointed out the 'obvious' superior alternative - 'only length 4 must be supported at this time'.) Noel PS: ISTR that about a month ago someone was asking for management papers from that era (but I was too busy to reply); two good ones are: - F. J. Corbat��, C. T. Clingen, "A Managerial View of the Multics System Development" https://multicians.org/managerial.html - F. J. Corbat��, C. T. Clingen, and J. H. Saltzer, "Multics -- the first seven years" https://multicians.org/f7y.html

2 years, 5 months

Re: Managers/architects (was: AIX moved into maintainance mode)

by Douglas McIlroy

> My guess is that Ivan Sutherland probably qualified back when he still > programmed ... I mean, after all, he invented the linked list in order to > implement his thesis program (Sketchpad) in about 1960. I don't know whether Sutherland invented the linked list, but if he did, it had to be before he worked on sketchpad. I attended a lecture about Lisp in 1959 in which McCarthy credited list-processing to IPL-V, whose roots Newell places in 1954. Sketchpad ran on TX 0, which became operational in 1956. My nomination for a triple-threat computer guy is Vic Vyssotsky. A great programmer, he invented the first stream-processing language (BLODI) and bitwise-parallel dataflow analysis. As an architect, he invented the single underlying address space for multics. As a manager, he oversaw the building of and later ran the lab that became AT&T Research. Finally he founded the DEC Cambridge Lab. He was a subtle diplomat, too, who more than once engineered reversals of policy without ruffling feathers. Relative to linked lists, I remember Vic perceptively touting the then startling usage J=NEXT(J).in Fortran. Doug

2 years, 6 months

Re: AIX moved into maintainance mode (fwd)

by Steve Nickolas

Accidentally sent this only to the person I was replying to. > I am getting some grief on Twitter too for "omitting" FreeBSD. I > didn't, but the BSDs don't fit either definition of "Unix". The > pre-1993 one being "based on AT&T code" -- after all, BSD (4.4 Lite r2 > was it? Before my time!) -- went to a lot of effort to eliminate AT&T > code. From what I've seen it's very much a gradual transition; 4.3-Tahoe starts to have the new code and UCB copyright notices with the predecessor of what we call the "BSD License" appearing in some of the source files. Then with Reno, a majority of the userland is open-sourced, and Net/2 is fairly complete. (Net/2 and 4.4BSD-Lite / Lite/2 were lacking a few things.) But even right up until the end things were in a state of flux. A few things weren't finished until much later by the FreeBSD, OpenBSD and NetBSD people. -uso.

2 years, 6 months

Re: Maintenance mode on AIX

by Joseph J. Mankoski ***PSI***

Hello -- Regarding "appliance-ization" (locking down / dumbing down) of commercially-available computer systems, and returning to the history of Unix (in the context of our current era), I am reminded of Ken Thompson's (excellent and humorous) panel presentation at the ACM Turing 100 conference I attended in 2012, imagining Alan Turing being brought to our time and given a current-generation computer system, etc. The webcast links for the "Systems Architecture" session, etc., on the main conference site, https://turing100.acm.org/, seem to be broken, however the video at this link works for me: https://dl.acm.org/doi/10.1145/2322176.2322182 (Ken's part starts at ~0:09:28.) Cheers, ***PSI*** <<<psi(a)valis.com>>> tuhs-request(a)tuhs.org writes: [...] > ---------------------------------------------------------------------- > > Message: 1 > Date: Wed, 18 Jan 2023 17:08:00 +0000 > From: segaloco <segaloco(a)protonmail.com> > Subject: [TUHS] Re: Maintenance mode on AIX > To: Clem Cole <clemc(a)ccc.com> > Cc: tuhs(a)tuhs.org > Message-ID: <zpdIicuX7AbN-y6hYho0eLOnHgzRs4iHa1UD6bxUyiTZhqZkg3Ha8TKWV > ASxWkDZitFw0JIopRVh7BRC2PzLFrF_Gjsb2yCi-uxJ3Yr3AtE=(a)protonmail.com> > Content-Type: multipart/alternative; > boundary="b1_7WKJsCnT0P2jggZLBLwbL2iRavDFXPykjXdIMPRs" > > Apple's unreasonable hardening has been the latest deterent to my ever wanting to use macOS as a personal driver. I've got a Mac as my daily driver for work, it can happily stay with work until I can decide how the filesystem is laid out and what folders I, as the root user, can and can't interact with from user land. I own my machine, not Apple. > > - Matt G. > ------- Original Message ------- > On Wednesday, January 18th, 2023 at 8:59 AM, Clem Cole <clemc(a)ccc.com> wrote: > >> On Wed, Jan 18, 2023 at 11:39 AM Larry McVoy <lm(a)mcvoy.com> wrote: >> >>> Someone once told me that if they had physical access to a Unix box, they >>> would get root. That has been true forever and it's even more true today, >>> pull the root disk, mount it on Linux, drop your ssh keys in there or add >>> a no password root or setuid a shell, whatever, if you can put your hands >>> on it, you can get in. >> >> A reasonable point, but I think it really depends on the UNIX implementation I suspect. Current mac OS is pretty well hardened from this, with their current enclaves and needing to boot home to Apple to get keys if things are not 100% right. Not saying you or I can not, but basically means the same cracking tricks you need to use for iPhones. It's not as easy as you describe. >> >> The ubiquitous Internet/WiFi changed the rules - as you can start to keep some set of keys somewhere else and then encrypt the local volumes. In fact, one of the things they do if mac OS boot detects that root has been modified (it has a crypto index stored away when it was made read-only), the boot rolls back to the last root snapshot -- since they are all read-only that works. In fact, it is a PITA to update/fix things like traditional scripts (for instance the scripts in the /etc/periodic area). Basically, they make it really unnatural to change the root files system, make a new snapshot and index (I have yet to see it documented although, with much pain, I previously created a procedure that is close -- i.e. it once worked on my pre-Ventura Mac - but currently -- fails, so I need to some more investigation when I can bring this back to the top of the importance/curiosity stack (I have a less than satisfying end around for now so I'm ignoring doing it properly). >> >> Clem >> ᐧ

2 years, 6 months

Burroughs funded $30,000 for a port to E-mode stack machine in 1983!

by ron minnich

I just stumbled across an old letter, from a VP of Burroughs to me and Steve Bartels, authorizing $30,000 for a port of Unix to the E-mode stack machine. I had forgotten getting it. Burroughs was famed for its stack machines. E-mode was a kind of last gasp attempt to save the stack architecture, which failed as far as I know, see this table: http://jack.hoa.org/hoajaa/Burr126b.html I worked as a hardware engineer on the A15. I also had been a Unix user for 7 years at that point and kept pointing out how awful the Burroughs CANDE time-sharing system was, and how much better Unix was. At some point I guess they asked me to put up or shut up. I got that money, and left Burroughs a week later for grad school. Funny note: A15 was Motorola ECL (MECL), and ran at 16 Mhz., considered fast at that time. We used a technique called "stored logic" which was, believe it or not, using MECL RAM to map logic inputs to outputs, i.e. implement combinational logic with SRAM. Kind of nuts, but it worked at the time. We also used a precursor of JTAG to scan it in. Those of you who know JTAG have some idea of how fun this had to be. One side effect of working with MECL is you realized just how well designed the TI 7400 SSI/MSI parts were ... MECL always just felt like an awkward family to design with. Another funny story, pointing to what was about to happen to Burroughs. We had an app that ran for hours on the stack machine. We quick ported it to a VAX, started it up, and headed out to lunch -- "this will take a while, let's go eat." We got to the front door and: "Oh, wait, let me hop back into the office,I forgot my jacket". And, noticed, the program was done in ... about 3 minutes. Not 8 hours. That's when we knew it was game over for Burroughs. If a picture of this letter would be useful in some archive somewhere, let me know, I can send it.

2 years, 6 months

In search of SunOS 4-era security advisory.

by Dan Cross

The security vulnerability in question could be briefly summarized as, "Fortran divide-by-zero gives root." I think that was just a specific manifestation of the underlying problem, though. More specifically it was actually due to failure to sanitize state after handling a SIGFPE (and possibly other signals as well?). I have a distinct memory of this, but can no longer find any evidence for it. Did I just make it up from whole cloth, or was this actually a thing? - Dan C.

2 years, 6 months

A few comments on porting the Bourne shell

by Paul Ruizendaal

London and Reiser report about porting the shell that “it required by far the largest conversion effort of any supposedly portable program, for the simple reason that it is not portable.” By the time of SysIII this is greatly improved, but also in porting the SysIII user land it was the most complex of the set so far. There were three aspects that I found noteworthy: 1. London/Reiser apparently felt strongly about a property of casts. The code argues that casting an l-value should not convert it into a r-value: <quote from "mode.h"> /* the following nonsense is required * because casts turn an Lvalue * into an Rvalue so two cheats * are necessary, one for each context. */ union { int _cheat;}; #define Lcheat(a) ((a)._cheat) #define Rcheat(a) ((int)(a)) <endquote> However, Lcheat is only used in two places (in service.c), to set and to clear a flag in a pointer. Interestingly, the 32V code already replaces one of these instances with a regular r-value cast. So far, I’d never thought about this aspect of casts. I stumbled across it, because the Plan 9 compiler did not accept the Lcheat expansion as valid C. 2. On the history of dup2 The shell code includes the following: <quote from “io.c”> rename(f1,f2) REG INT f1, f2; { #ifdef RES /* research has different sys calls from TS */ IF f1!=f2 THEN dup(f1|DUPFLG, f2); close(f1); IF f2==0 THEN ioset|=1 FI FI #else INT fs; IF f1!=f2 THEN fs = fcntl(f2,1,0); close(f2); fcntl(f1,0,f2); close(f1); IF fs==1 THEN fcntl(f2,2,1) FI IF f2==0 THEN ioset|=1 FI FI #endif } <endquote> I’ve check the 8th edition source, and indeed it supports using DUPFLG to signal to dup() that it really is dup2(). I had earlier wondered why dup2() did not appear in research until 10th edition, but now that is clear. It would seem that the dup of 8th edition is a direct ancestor to dup() in Plan 9. I wonder why this way of doing things never caught on in the other Unices. 3. Halfway to demand paging I stumbled across this one because I had a bug in my signal handling. From early days onwards, Unix supported dynamically growing the stack allocation, which arguably is a first step towards building the mechanisms for demand paging. It appears that the Bourne shell made another step, catching page faults and expanding the data/bss allocation dynamically: <quote from “fault.c”> VOID fault(sig) REG INT sig; { signal(sig, fault); IF sig==MEMF THEN IF setbrk(brkincr) == -1 THEN error(nospace); FI ELIF ... <endquote> This was already present in 7th edition, so it is by no means new in 32V or SysIII -- it had just escaped my attention as a conceptual step in the development of Unix memory handling.

2 years, 6 months

C with Classes reference manual

by Ron Natalie

Here’s a stretch, but does anybody have a copy of the 1982-ish C With Classes Reference Manual kicking around. I can take it in n/troff or a more modern format if you have it.

2 years, 6 months

Re: A few comments on porting the Bourne shell

by Douglas McIlroy

> segaloco via TUHS writes: >> I think that's a good point that scripting problems may be >> a symptom of the nature of the tools being used in them. > I think that you're hinting at something different. > To the best of my recollection, scripting languages were originally > intended and used for the automation of repetitive personal tasks; > making it easier for users who found themselves typing the same > stuff over and over again. Indeed! > Somewhere along the line people forgot > how to use a compiler and began writing large systems in a variety > of roughly equivalent but incompatible interpreted languages. Can > one even boot linux without having several different incompatible > versions of Python installed today? So I don't think that it's the > nature of the tools; I think that it's people choosing the wrong > tools for the problems that they're trying to solve. > Jon The forgotten compilers were typically used to supply glue to paste major tools together. The nature of that glue---often simple data reformatting--inspired tools like sed and awk. Each use of a tool became a process that saved many minutes of work that would in a scriptless world be guided by hand, boringly and unreliably. Yet glue processes typically did only microseconds of "real" work. In the name of efficiency, the operations began to be incorporated directly into the shell. The first inklings of this can be seen in "echo" and various forms of variable-substitution making their way into the v7 shell. The phenomenon proliferated into putting what were typically canned sed one-liners (but not sed itself) into the shell. Lots of specializations crowded out universality. A side effect was an explosion of knowledge required to write or understand code. Such is the tragedy of "forgetting compilers". Doug

2 years, 6 months

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