TUHS

tuhs@tuhs.org

2 participants
6532 discussions

Draft v5: London and Reiser's UNIX VAX port paper, reconstructed

by G. Branden Robinson

Hi folks, A few months ago I reported on my efforts to reconstruct London & Reiser's paper on their port of Unix to the VAX-11/780.[1] I formerly characterized this as "the UNIX/32V port", but since London & Reiser's paper predates the release of Seventh Edition Unix by about six months, UNIX/32V came _after_ Seventh Edition by about the same number of months, and the pace of Unix development was particularly ferocious in this period[2], I felt that my identification of London & Reiser's work with UNIX/32V may have been hasty. I also may have overinterpreted Dennis Ritchie's words on the subject. "Tom London and John Reiser, working from the 7th Edition and the Interdata 8/32 system, generated a VAX 11/780 version of the system, which, in its distribution format, would be called 32V." That phrase "in its distribution format" could cover a variety of changes, some of which perhaps did not match London & Reiser's intentions or views expressed in their paper. More conservative implications seemed prudent. I'd thus like to present what I consider to be my "final" draft, subject of course to feedback from these mailing lists. I'm pleased to report that I've addressed all of the XXX points I identified in the source of my first draft, points where I felt groff mm could be enhanced to aid the rendering of historical documents like this. I consequently expect groff 1.24's mm package to support several new features prompted specifically by this work. Quoting the forthcoming NEWS file... * The m (mm) macro package now supports a user-definable hook macro `AFX`, which if defined is called by `AF` in lieu of the latter's normal operation. Applications include customization of letterhead. * The m (mm) macro package now supports a user-definable hook macro `RPX`, which if defined is called by `RP` to format the reference list caption string `Rp` instead of the default formatting. * The m (mm) macro package now supports an `Aumt` string to suppress the appearance of positional arguments to the `AU` macro in the document heading used by memorandum types 0-3 and 6. By default, all such arguments appear, except the second (author initials). For example, a value of "3 4" more accurately reproduces London & Reiser's 1978 paper describing the porting of Unix to the VAX-11/780. * The m (mm) macro package now supports an `Rpfmt` string specifying the `LB` macro arguments that the package uses to format the items in a reference list. * The m (mm) macro package no longer superscripts _and_ brackets a reference mark (the `Rf` string). Instead, the new `Rfstyle` register controls its formatting. The default, 0, selects bracketing in nroff mode and superscripting in troff mode. Set `Rfstyle` to 3 in a document to obtain groff mm's previous mark formatting behavior. [I might still update or revert the changed default; I want to research the behavior of historical mm implementations.] The "32vscan.pdf" document from which I prepared this reconstruction is available at Dennis Ritchie's memorial home page.[3] I have attached the reconstructed mm source document and two PDFs, rendered with groff 1.23.0 (the current stable release), and groff Git HEAD (exercising the new features listed above).[4] I offer the caveat that these cannot be pixel-perfect recreations because (1) I have no information about the precise paper dimensions or margins London & Reiser used[5]; (2) the fonts employed in rendering the documents are not identical, metrically or otherwise; and (3) AT&T and GNU troffs use different hyphenation systems and therefore sometimes break words differently. These factors all impact the placement of line and page breaks, and these are avowedly and clearly distinguishable. There are furthermore a few discrepancies that I decided weren't worth the trouble at this time to reconcile, like selective encroachment of cover sheet material beyond the page margins. None affect the utility of the document (in my opinion). With that large disclaimer in place, I welcome feedback on the quality of the reproduction. Finally, I reiterate my encouragement that the document be _read_. In my opinion, the final two sections "Commands" and "Software portability" are well worth consideration in hindsight. To the extent that we continue to boast, sometimes glibly, of C as a "portable assembly language", be it in its current ISO C23 incarnation; as ANSI C89, the last revision blessed by Ritchie; or in the form used when London and Reiser wrote, their experiences and recommendations laid out a program of better delivering on that promise. Regards, Branden [1] https://www.tuhs.org/pipermail/tuhs/2024-June/030041.html [2] 1980, for example, saw releases of 3BSD, System III, PWB/UNIX 2.0, and 4BSD. [3] https://www.bell-labs.com/usr/dmr/www/portpapers.html [4] You may notice a difference in the sizes of the two PDFs, surprising in light of their shared source document. This is thanks to a new feature forthcoming in Deri James's gropdf(1) output driver: font subsetting. [5] ...or where, if anywhere, the authors "cheated" the margins temporarily, for instance with `ll` or `pl` requests. Even with mm macro package sources available, such things would be invisible to the reconstructor.

8 months, 2 weeks

Old troff files (1988-2007)

by Jacobson, Doug W [E CPE]

Folks: Long story short, I have a unpublished manuscript that a faculty member in my department wrote late 1980's early 2000's. He did the entire thing in troff, eqn, and pic. The faculty member is still alive. A publisher is interested in the manuscript. I have all of the source files on an old unix machine that still has troff, eqn and pic. It also has groff. This issue is that the pic commands are bracketed by .G1 and .G2 not .PS & .PE. The original machine he would have used would have ran AT&T Sys V on an AT&T 3B20. Below is one of the files. Any thoughts on the .G1 .G2? I can get the files that have only eqn and troff to create postscript, but the .G1/.G2 is not understood by pic. I tried replacing the .G1/.G2 with .PS/PE and it failed. I must be missing another program that uses the .G1/2 Thanks .sp -3.5 .fp 1 Z .fp 2 XI .ps 11 .tl ' ' '1-10' .EQ delim $$ gsize 11 .EN .po 0.9i .vs 15 .G1 frame wid 5.7 ht 6.0 invis coord x 0.2, 100 y -40, +22 log x grid left from -30 to +20 by 10 "" grid left from -40.04 to +19.96 by 10 "" grid left from -39.96 to +20.04 by 10 "" grid left from -39 to +22 by 1 "" grid bot from 0.4 to 40 by *10 "" grid bot from 1 to 100 by *10 "" grid bot from 0.2 to 20 by *10 "" grid bot from 0.3 to 30 by *10 "" grid bot from 0.5 to 50 by *10 "" grid bot from 0.6 to 60 by *10 "" grid bot from 0.7 to 70 by *10 "" grid bot from 0.8 to 80 by *10 "" grid bot from 0.9 to 90 by *10 "" ticks out left from -40 to +20 by 10 ticks out bot from 0.2 to 20 by *10 ticks out bot from 0.4 to 40 by *10 ticks out bot from 1 to 100 by *10 draw solid 0.2 19.93 2 19.93 10 5.97 100 -34.02 new solid 0.2 20.07 2 20.07 10 6.05 100 -33.95 new dotted for i=0.45 to 23 by *1.05 do { w=i*i f=200/sqrt(w*w+104*w+400) next at i,20*log(f) } label left "\u\udB \d\d" label bot "\(*w, rad/s" .G2 .in 2 Fig. 1.4. Graph of the magnitude in dB of $H(s)~=~200 over{s sup 2~+~12^s~+~20}^,$$~s~=~j^omega$. Doug Jacobson University Professor, Dept. Electrical & Computer Engineering Sunil & Sujata Gaitonde Professorship in Cybersecurity Director: ISU Center for Cybersecurity Innovation and Outreach Mail Address: 2520 Osborn Dr, 2215 Coover Hall Iowa State University PH: (515) 294-8307 Fax (515) 294-8432 Office: 371 Durham Hall Center web site: http://www.cyio.iastate.edu/<https://urldefense.com/v3/__http:/www.cyio.iastate.edu/__;!!DZ3fjg!oVZir7OL…> Personal web site: http://www.dougj.net<https://urldefense.com/v3/__http:/www.dougj.net/__;!!DZ3fjg!oVZir7OL4VMZHCY…>

8 months, 2 weeks

Re: lilian schwartz has died

by Douglas McIlroy

> lilian worked at bell labs in the 80s (and maybe 90s) > around tech and films and suchlike. Lillian was a real pioneer. She began collaborating at the Labs in the mid 1960s. Doug

8 months, 2 weeks

lilian schwartz has died

by andrew＠humeweb.com

lilian worked at bell labs in the 80s (and maybe 90s) around tech and films and suchlike.

8 months, 2 weeks

by arnold＠skeeve.com

Hi All. I'm working on revising my book on basic *nix programming, and for the new chapter on sockets, I want to include some code from 4.2 BSD. Is there a copyright file somewhere for that code? I'm sure it's copyright the Regents of the University of California, but I'd like to include the text of the copyright in the book, so that everything's clear. Thanks! Arnold

8 months, 2 weeks

V8 and V9 manual covers

by Aharon Robbins

Hello All, I took a picture of my V8 and V9 manuals the other day. It's available at https://www.skeeve.com/V8-V9-Covers.jpg. @segaloco: This one's for you. :-) Enjoy, Arnold

8 months, 3 weeks

Re: BTL Involvement in Publication Imagery?

by Douglas McIlroy

Unix folk were barely involved in the branding or advertising of the system. I recall that we got to proofread and edit the first Unix ad, but essentially nothing later. Nor did we contribute to the cover designs of the 7th edition trade verson or the 8th-10th in-house versions of the manual. Doug

8 months, 3 weeks

BTL Involvement in Publication Imagery?

by segaloco

So in the course of AT&T's involvement with UNIX, a number of different images and motifs have graced advertisements and covers of literature, among them: - Letter Blocks (V7 HRW manuals, Release 4.0 Starter Packages) - Criss-crossing grid lines on a black background (Release 5.0/SVR1) - Variations on an image of earth with UNIX superimposed (SVR3/SVR4) - Covers mirroring publication motifs of other AT&T products and literature (SVR2/SVR3) Did the folks actually involved in the production of UNIX have any influence on the choice of design motifs for such materials, or would those sorts of decisions have been largely in the hands of marketing folks several layers removed from the Labs? My understanding is that this sort of visual branding started in the early 80s, with the earliest example of a printed piece of UNIX literature outside of generic Bell Laboratories covers I'm aware of being the "Starter Package" documents featuring UNIX spelled out on four letter blocks in primary colors. Everything I've seen branded predating these 1981 publications is either 8.5/11 pages in a Bell Labs or Western Electric report cover or the form factor of the Release 3.0 manual using generic Bell Labs covers. I'm certainly intrigued if anyone has any recollection of any sort of visual motifs in play prior to 1981. - Matt G.

8 months, 3 weeks

Re: groff_man.7.man.in: Some remarks and editorial changes for this man page

by Douglas McIlroy

The titled post reminds me of Ted Dolotta, a guru of PWB Unix, whose eye for editorial detail was unsurpassed. He could spot the difference between italic and roman periods at twenty paces. Bjarni is in good company. Doug

8 months, 3 weeks

Re: Minimum Array Sizes in 16 bit C (was Maximum)

by Douglas McIlroy

> C's refusal to specify dynamic memory allocation in the language runtime > (as opposed to, eventually, the standard library) This complaint overlooks one tenet of C: every operation in what you call "language runtime" takes O(1) time. Dynamic memory allocation is not such an operation. Your hobbyhorse awakened one of mine. malloc was in v7, before the C standard was written. The standard spinelessly buckled to allow malloc(0) to return 0, as some implementations gratuitously did. I can't imagine that any program ever actually wanted the feature. Now it's one more undefined behavior that lurks in thousands of programs. There are two arguments for malloc(0), Most importantly, it caters for a limiting case for aggregates generated at runtime--an instance of Kernighan's Law, "Do nothing gracefully". It also provides a way to create a distinctive pointer to impart some meta-information, e.g. "TBD" or "end of subgroup", distinct from the null pointer, which merely denotes absence. Doug

8 months, 4 weeks

Why groff ms doesn't completely support historical documents

by G. Branden Robinson

Someone on the TUHS list mailed me privately, prompting me to write this lengthy apology (in the classical sense) of why groff doesn't make a certain application easier. I have slightly revised my response. This message also may serve as a summary of the challenges that need to be overcome if someone else wants to tackle the job, and potentially contribute it to groff. [person creates PDFs of historical Unix documents (many of which are written using the ms macros) and wishes groff ms made the task easier] I sympathize. I sometimes render historical documents, so I prescribed in groff ms's documentation the approach that I take myself. I decided against trying to support a "-matt" or "-msatt" option in groff because it's flatly impossible to know which definition of `UX` to use. Even a date declaration in the document sheds little light, as we then have to consider the question of whether we want fidelity to the actual state of the mark at the time of that declared date, or to what would have been rendered in the author's environment--and they may have been using an ms that wasn't "up to date" in the same respect. That information, too, is not recorded in the document.[1] Providing all the macros _except_ `UX` didn't seem likely to satisfy users since that's the most important one! It shows up in body text whereas all the others seldom do--if you can live without the cover page then, often, you're golden. Except for `UX`. Finally there is the name collision problem with Berkeley. 4.2BSD and later ms defined `CT` and `TM` macros (aspects of their "thesis mode") and once again there's no declarator within the document to tell you which dialect of ms is in use. This one can be heuristically figured out with pretty good odds, I suspect, but troff works as a filter--what was I going to do, write a preprocessor just for this? (Hmm, maybe grog(1) could do it, and that would be in its wheelhouse. But there's no point until and unless we reimplement support for Berkeley thesis mode in the first place [so that grog has an option argument to report], and that is an undertaking I have demurred.[2]) It seemed like a moderate amount of work for almost zero upside. It's also hard to validate/verify my work. The only historical troffs to which I have access are Seventh Edition Unix troff (1979, before Kernighan) and DWB 3.3 (early 1990s). It's a right pain in the butt to inspect typesetter output on V7 because I have nothing that emulates a C/A/T or translates it to device-independent troff output for a "ditroff"-style device description that Kernighan troff, DWB/Hierloom Doctools troff, or GNU troff could use. And even if I had either of those, they'd have to be vetted to a _high_ degree of quality before they'd be fit for purpose; else I wouldn't know whether I was chasing bugs in the groff ms macros or the C/A/T emulator/translator. So, to summarize, I confine my compatibility efforts to _nroff_ output, and rule the Bell Labs "site" macros out of scope. I feel there is not much more I can do, and have confidence my results, without resources that I'm lacking. I hope this sheds some light on my reasoning. Regards, Branden [1] Still, if someone wants to start, I'd start here. https://minnie.tuhs.org/cgi-bin/utree.pl?file=V10/vol2/ms/tmac.s [2] One person, ever, has requested it, 20 years ago. And I have no specimens of input or corresponding model output rendered by an "authentic" BSD troff [formatter executable PLUS support files] against which to develop a reconstruction. (On the bright side, the Berkeley modifications to the once-encumbered AT&T "tmac.s" are, of themselves, presumably BSD-licensed.) https://savannah.gnu.org/bugs/?64455

8 months, 4 weeks

30 days of awktober

by Rich Salz

Someone is trying to write something interesting about awk every day of this month. The thread starts here: https://mastodon.mit.edu/@eichin/113240121988228925

8 months, 4 weeks

Re: UNIX NEWS, volumes 1-7 out there?

by sjenkin＠canb.auug.org.au

In Sept 2019 Warner Losh was looking for copies of the first volumes of UNIX NEWS / Login. Clem Cole noted that the Usenix Archives were also looking. Kurt H Maier, noted he had pages from 1976, Volume 1, Number 4. Jeremy C. Reed pointed to multiple items available online. His email appears in a separate email thread on TUHS. <https://tuhs.org/mailman3/hyperkitty/list/tuhs@tuhs.org/thread/C2L346YQTFU2…> <https://tuhs.org/mailman3/hyperkitty/list/tuhs@tuhs.org/message/FMSC3426GK2…> I stumbled on UNIX NEWS Number 1 in the Internet Archive <https://archive.org/details/unix_news_july-30-1975> Which is from a near complete Usenix collection of ‘;login' from 1975 to 2000 <https://archive.org/details/usenix-login?tab=collection&sort=-date>. 1979 (Volume 4) is missing from the series [ as at Oct 2024 ] I wasn’t able to navigate the Usenix website to find the Archives Clem Cole mentioned, to confirm they also had copies. I also stumbled on a pointer to “John Gilmore’s original scans” from 1975 - 1978, presumably the base for the Usenix / Archive.org set. <http://www.toad.com/early-usenix-newsletters/> It’s seems that the call for materials was pretty successful. -- 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

8 months, 4 weeks

Fwd: Trove of CSTR's

by Warren Toomey

All, I got this e-mail and thought many of you would appreciate the link. Cheers, Warren ----- Forwarded message from Poul-Henning Kamp ----- I stumbled over this: https://www.telecomarchive.com/lettermemo.html is the TUHS crew aware of that resource ? ----- End forwarded message -----

9 months

Origins of "Unix Philosophy"

by Phil Budne

I'm wondering if there are places where people who were in the Unix Room wrote about the origins and evolution of what people (at least used to(*)) refer to as "Unix Philosophy", and since some are in THIS (TUHS) room, what they might have to say about it. How much was in reaction to the complexity of Multics, and how much was simply a response to the limited address spaces of available and affordable hardware? Eric S. Raymond wrote in "The Art of Unix Programming" quoting Doug McIlroy and Rob Pike: http://www.catb.org/esr/writings/taoup/html/ch01s06.html And I wonder if they care to comment on it? I have trouble taking ESR as authoritative, as, it seems to me that Research Unix was more a product of the "Cathedral" (or at least a contained community) than the "Bazaar" (at least the modern bazaar, where everyone needs to leave a new feature grafito on the town walls), and ESR A side question for Rob Pike, is the "Not only is UNIX dead, it's starting to smell really bad." quote accurate? Was it in reaction to BSD, GNU, or all of the above? (*) I say "used to", because, for the most part, minimalism seems to have left the building. I can't look at modern GNU utilities, and many, if not most open source packages and think they've gone WAY past classic Unix minimalism, especially since I remember hearing that Bell Research had happily stripped excess features (removal of "cat -s" sticks in my mind) from later day research Unix, and because Stallman is said to have coined the term "New Jersey" style as a synonym for what Richard P. Gabriel called "Worse is Better", which seems, an attack on minimalism (nothing less than "the right thing" is acceptable) Worse is.... readings: https://dreamsongs.com/WorseIsBetter.html https://dreamsongs.com/RiseOfWorseIsBetter.html https://dreamsongs.com/Files/IsWorseReallyBetter.pdf https://dreamsongs.com/Files/worse-is-worse.pdf Anti-flamage disclainmers: Inclusion of links above does not imply any agreement on my part! My apologies in advance for any offense, misquote, or misunderstanding on my part.

9 months

Re: On computerese

by jnc＠mercury.lcs.mit.edu

> From: Rik Farrow <rik(a)rikfarrow.com> > Was the brevity typical of Unix command names a function of the tiny > disk and memory available? Or more a function of having a Teletype 33 > for input? I'm not sure the answer was ever written down (e.g. in a memo); we will probably have to rely on memory - and memories that far back are now fairly thin on the ground by now. Perhaps Mr. McIlroy (or Mr. Thompson, if we're _really_ lucky) will humor us? :-) I have the impression that some of the names are _possibly_ inherited from Multics (which the early Unicians all used before Unix existed) - but maybe not. The command to list a directory, on Multics, is 'ls' (but see below) - but the Multics qcommand to remove a file is 'del' (not 'rm'); and change working directory is 'cwd'. So maybe ls' is just chance? Multics had a 'feature' where a segment (file) could have additional names (to the main name), and this is used to add short aliases to many commands, so the 'base name'' for the directory list command is 'list'; 'ls' is a short alias. A list of Multics commands (with short forms) is available here: https://www.multicians.org/multics-commands.html I'm not sure how early that alias mechanism came in, though; my copy of "Introduction to Multics" (February, 1974) doesn't have short names (or, at least, it doesn't use them). It won't have anything to do with disk and memory. Having used a Teletype, it would take noticeably longer to type in a longer name! It's also more effort and time. I would expect those are the reasons for the short names. Noel

9 months

Re: Fwd: Trove of CSTR's

by Douglas McIlroy

> I wonder what happened to the amazing library at Murray Hill. Last I knew, the Bell Labs archives were intact under supervision of a professional archivist. Formally speaking, the archives and the library were distinct entities. The library, which was open to self service 24 hours a day, declined rapidly after the bean counters decreed that it should henceforth support itself on rental fees. Departments immediately turned to buying books rather than borrowing them. It's very likely that this was bad for the Labs' bottom line, but the cost (both monetary and intellectual) was not visible as a budgetary line item. The 24-hour library contributed to one of Ken's programming feats. Spurred by a lunchtime remark that it would be nice to have a unit-conversion program, Ken announced units(1) the next morning. Right from the start, the program knew more than 200 units, thanks to a book Ken grabbed from the library in the middle of the night. Doug

9 months

Re: Fwd: Trove of CSTR's

by Douglas McIlroy

> That CSTR number 1 is nicely formatted, is that troff? The archive's CSTR 1 is ersatz. It's a 1973 journal article obtained from JSTOR. I imagine the manuscript was largely copied from the CSTR, but the printed paper certainly differs in meta-content and in layout, say nothing of font. Having gone through the usual route of journal submission and revision, the body text is probably not word-for-word identical to the CSTR either. Doug

9 months

Re: Classic FoxTrot cartoon

by norman＠oclsc.org

Clem Cole: Interesting -- 'Jason' had always been a Pascal hacker when the strip was first created. As I recall, Berkeley Breathed had Wendell (his hacker character) comment on that during the time of Pascal/C Wars. ==== But Jason later was revealed to be wearing Unix underpants: https://www.gocomics.com/foxtrot/2002/02/25 Norman Wilson Toronto ON

9 months, 1 week

Classic FoxTrot cartoon

by arnold＠skeeve.com

https://www.gocomics.com/foxtrotclassics/2024/09/27 IIRC correctly the original version left out the \n. I was told he got some many comments that he later published a strip that was just: \n Arnold

9 months, 1 week

Any Surviving BELLMAC-8 Development Tools?

by segaloco

Hello everyone, I've found myself in the exceptionally fortunate circumstance of securing ownership of a MAC-TUTOR BELLMAC-8 SBC unit. It is still in shipment so I can't assess its operation yet, but I was wondering if anyone is aware of any surviving assemblers, linkers, etc. for this architecture? If not, I'm prepared to roll my own based on available documentation, but figured I'd ask to see if there's anything I can start with. From what I can tell, the main development environment was PWB, specifically the Bell System internal varieties, with the BTL edition of Release 5.0 literature describing things like m8as(1), m8cc(1), etc. as Division 452 Computer Center standard commands. There is a bit of information here as well: http://ferretronix.com/march/sbc/mactutor/ Thanks for any tips! Regardless of how much I can manage to do with it, I'll be sure to get some good pictures and take some notes on what I am able to figure out with the thing. I presume the Gunkies wiki would be a good place to document that sort of thing? - Matt G. P.S. Pardon if this belongs on COFF, I figured since UNIX was the canonical development system and it is also a Bell Labs thing, I'd ask here first.

9 months, 1 week

kernel boots kernel in 1977

by ron minnich

I noticed there are kexec talks this year at Linux Plumbers. Kexec, kernel boots kernel, has had a 25 year gestation in Linux, but it looks like it's finally coming together, driven by need. Thereby hangs a tale. in 1977, I was working at udel with Ed Szurkowski, the first sysadmin of the Unix systems we got in 1976 (first machine was an 11/70). Ed was a gifted engineer and did all kinds of neat work on v6. He later went to the Labs once he got his PhD and I lost track of him. Ed got tired of watching the bootstrap slowness, and wrote a system call that did the following: 1. load kernel in memory from system call argument 2. put special signature in low memory telling bootstrap "look in memory" 3. reboot via reset. Now, this works, because back then, ROM boot code did not zero memory. Memory was unchanged across reset. So the bootstrap could find the magic bits and start the kernel. I've lost the code, I carried the listings for decades but finally dumped them. A shame. But I'm wondering: is Ed's work in 1977 the first "kernel boots kernel" or was there something before?

9 months, 2 weeks

Re: Maximum Array Sizes in 16 bit C

by Douglas McIlroy

> The array size} limit that I found through trial and error is (2^15)-1. > Declaring an array that is [larger] results in an error of "Constant required", On its face, it states that anything bigger cannot be an integer constant, which is reasonable because that's the largest (signed) integer value. Does that version of C support unsigned constants? Doug

9 months, 2 weeks

Free computing books in SF area

by John Floren

It's a bit off-topic but Warren OK'd it: I'm trying to tidy the absolute dragon's hoard I call an office, so I'm looking to give away some books I haven't touched in years. These are free for the taking for anybody who wants to drive to SF and get them. I'd really prefer for somebody to take them all at once, of course. - DEC PDP11/70 Processor Handbook - DEC VAX11 Architecture Handbook - DEC PDP11 Peripherals and Interfacing Handbook - DEC Introduction to Programming (PDP-8) - Programming Languages: History and Fundamentals (Sammet) - Computer Networks, 1st ed (Tanenbaum) - Modern Operating Systems, 2nd ed (Tanenbaum) - Operating Systems Design and Implementation, 1st ed (Tanenbaum) - Advanced Programming in the UNIX Environment (Stevens) - Computer Architecture and Organization, 2nd ed (Hayes) - Compilers: Principles, Techniques, and Tools (Aho, Sethi, Ullman) - The Undocumented PC, 2nd ed (van Gilluwe) - Cybernetics (Wiener) If you want these, please email me *off-list* to set it up. John

9 months, 2 weeks

Re: kernel boots kernel in 1977

by jnc＠mercury.lcs.mit.edu

> From: Ron Minnich > Ed got tired of watching the bootstrap slowness This may be a dumb question (in which case, my apologies), but which part of booting a PDP-11 UNIX was slow? And thus, which parts did he bypass in a 'quick reboot'? (I'm having a bit of a hard time working it out.) I can think of the following stages as potentially being 'slow': 1 - reading in the kernel image from disk 2 - sizing/clearing main memory 3 - loading running /etc/init 3A - creating all the 'loqin's 3B - starting all the daemons/etc with /etc/rc (There's obviously a conflict between 2 and 3*; one can't avoid 3* if one does 2.) Which ones did he want to avoid? Avoiding 3* puts some limitations on the system, obviously, because it means one has to keep running processes around; the process table has to have the same format (and be in the same location - or it has to be moved before the new system is started). (Technically, I guess one would have to save the inode and file tables, too; there isn't enough saved data in the kernel to re-open files, plus there are file read/write ocation pointers, etc.) One could sort of do 2 also, if one were prepared to 1) swap all processes out to secondary storage before 'rebooting', and ii) saving the process table. > But I'm wondering: is Ed's work in 1977 the first "kernel boots kernel" > or was there something before? Are you talking about for UNIX, or across all operating systems? I don't have that broad a memory any more, to know - did TWENEX have something like that? Noel

9 months, 2 weeks

← Newer
1
...
5
6
7
8
9
10
11
...
262
Older →

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

1996

1995

1994

1993

1992

1991

1990

TUHS