- TUHS - www.tuhs.org

by jnc＠mercury.lcs.mit.edu

> From: Clem Cole > I'm thrilled to see the 11 kept alive. Ditto. The most elegant archtecture ever, IMO. > I was under the impression ??Ken?? had created them for B > independently (which, of course, was first on the PDP-7). "The Development of the C Language", by Dennis M. Ritchie: https://www.bell-labs.com/usr/dmr/www/chist.html says: The PDP-7, however, did have a few `auto-increment' memory cells, with the property that an indirect memory reference through them incremented the cell. This feature probably suggested such operators to Thompson; the generalization to make them both prefix and postfix was his own. Indeed, the auto-increment cells were not used directly in implementation of the operators, and a stronger motivation for the innovation was probably his observation that the translation of ++x was smaller than that of x=x+1. Note the "probably"; unless Ken remembers, and says something, that's probably the best we are going to get. > I did not think the PDP-7 ISA includes addressing modes in the same > manner as the 11. .. I thought PDP-7 is a very simple instruction (and > small) with an AC, Link/Indirection and a PC - it reminded me of the > PDP-8 more than anything else The PDP-4, -7 and -9 are all the same architecture (very similar to the PDP-1, but simplified a bit), differing only in implementation. (Most PDP-7 code will run on a -9, un-modified.) Basic instructions look like: Instructions had a 4-bit opcode ('000'-'054'), 1 bit of indirect, and 13 bits of address. It was a load-store architecture, with a single accumulator. So, yes, similar to an -8. There are other opcodes for non-memory operations ('074' opcode), and I/O ('070'), using bits in the 'address' field. ('060' opcodes were for the optional EAE.) All of the -4/-7/-9 had the 'auto-increment on locations 010-017' when indirecting through them' feature. Bitsavers has fairly complete docs on them all: http://www.bitsavers.org/pdf/dec/pdp4/ http://www.bitsavers.org/pdf/dec/pdp7/ http://www.bitsavers.org/pdf/dec/pdp9/ Noel

3 years, 3 months

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Re: [TUHS] [tuhs] PDP-11 and early Unix

by jnc＠mercury.lcs.mit.edu

> From: "Nelson H. F. Beebe" > there is a nice compact history of the PDP-11 and early Unix at this > new article: Not a bad artcle, but it had a number of minor errors, which I found irritating. They should have gotten an expert to proof it. Here are some: registers could access any other register - as well as memory or direct data - using one of the six different addressing modes I think 'instruction' may have been meant for the first "register"; as written it makes on sense. (Unlike the PDP-10, in the PDP-11, a register can't address another register.) Oh, and there are eight addressing modes. use of labels instead of hard-coded addresses makes it easier to program and makes the code relocatable in memory I'm not sure whether the writer knows the difference between 'PC-relative addressing' (a PDP-11 feature; code that will run at any address, without _any_ changes to the binary) and 'relocatable binary (which uses labels, as he describes). - but is not PDP-11 specific. The program counter can be accessed like any of the other registers ... The program counter is intended to support jump, branching, and other control flow instructions. Uh, no. It's not clear _exactly_ what was meant here, but... having the PC as a general register is for PC-relative addressing of operands, immediate data, and absolute addressing of operands. Jumps, branches, etc don't use the fact that the PC is a general register. These are the key advantages of assembly programming over high-level languages - assembler code always runs faster and uses less memory. Not really, with modern compilers. The number above represents -2. A commenter caught this one. Just use a $ to represent a decimal number In UNIX assembler, "$" means 'immediate data'; a trailing "." means decimal. And a tip of the hatly hat for getting this: Although the ++ and - operators in C are equivalents of DEC and INC instructions, they were inspired by an addressing mode in the PDP-7. right. Noel

3 years, 3 months

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[tuhs] PDP-11 and early Unix

by Nelson H. F. Beebe

Although the story is well known to members of this list, there is a nice compact history of the PDP-11 and early Unix at this new article: A brief tour of the PDP-11, the most influential minicomputer of all time https://arstechnica.com/gadgets/2022/03/a-brief-tour-of-the-pdp-11-the-most… It describes PDP-11 assembly language, and shows the booting of a Unix system on a simh instance. It also includes the famous picture of Dennis and Ken at a PDP-11 console, and concludes with a link to an online text of a book about PDP-11 assembly language programming. ------------------------------------------------------------------------------- - Nelson H. F. Beebe Tel: +1 801 581 5254 - - University of Utah FAX: +1 801 581 4148 - - Department of Mathematics, 110 LCB Internet e-mail: beebe(a)math.utah.edu - - 155 S 1400 E RM 233 beebe(a)acm.org beebe(a)computer.org - - Salt Lake City, UT 84112-0090, USA URL: http://www.math.utah.edu/~beebe/ - -------------------------------------------------------------------------------

3 years, 3 months

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Documenter's Workbench versions

by Kevin Bowling

I am reading some UNIX text processing books and am interested in the lineage of Documenter's Workbench. I see documentation of 1.0 (i.e https://archive.org/details/sysv-dwb/page/n5/mode/2up) I see a copy of 2.0 for 3B2 (i.e. https://archives.loomcom.com/3b2/software/Documenters_Workbench/) >From there things get a little less clear, it seems like we jump to 3.2 with SysVR3.2? Then there is a 3.3 version https://github.com/n-t-roff/DWB3.3 One of my books from the late 80s references 3.4 available as a source code purchase independent of UNIX. Then it appears SGI might have had a 4.x strain? (i.e. https://archive.org/details/sgi_Documenters_Workbench_4.1.3) Heirloom is derived from OpenSolaris which is derived from? Can anyone firm this lineage up a bit; and is 4.x an SGI thing or what (I extracted the image, the relnotes inside might as well not exist). Regards, Kevin

3 years, 3 months

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Re: [TUHS] [PiDP-11] Fun with Fortran on the PiDP-11

by Adam Thornton

> On Mar 12, 2022, at 2:02 PM, Rob Pike <r(a)golang.org> wrote: > > Indeed. Be careful about the code Numerical Recipes if you are doing > important numerical work. > For simple stuff it's fine, of course, but floating point is a > minefield that requires expert navigation. > > -rob That's the seductive trap of floating-point numbers, isn't it? They invite us to think about them as if they were the real numbers, but they are very, very much *not* the real numbers. And yet, most of the time, for most applications, if you treat them as if they were, you get plausible results. Adam

3 years, 3 months

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pcc struct return quirk

by Alexander Monakov

Hello, I'm trying to understand a quirk in 32-bit x86 code generation conventions: on Linux, when returning a structure from a function by value: struct S { int i, j; }; struct S f(int x) { return (struct S){x, sizeof(void*)}; } the caller reserves space for the returned structure and passes a pointer to that space as an 'invisible' extra argument, which is prepended to the argument list; the callee returns this pointer (although the caller knows it anyway); it's as if the function is transformed to struct S *f(struct S *ret, int x) { ret->i = x; ret->j = sizeof(void*); return ret; } with one essential difference: the function 'f' itself is responsible for popping the extra argument off the stack (the 'x' argument is popped by its caller). This necessitates using the return-with-immediate ('ret 4') instruction instead of the normal 'ret'; this is the only instance where this variant of the 'ret' instruction is used in code generation for C programs on Linux normally. I wonder how this exception came to be. Early versions of GCC (e.g. gcc-1.27) did not implement this convention, i.e. the caller was responsible for popping the invisible pointer similar to the normal arguments. The "callee-pops" variant was implemented later for "compatibility with other compilers", and the option that controls this is called -fpcc-struct-return, which also disables returning small structures in registers (in the example above GCC would return the value in EDX:EAX register pair). Operating systems differ on following this convention. For example, FreeBSD and OpenBSD do not, and neither does Windows. Looking at 386BSD tree in unix-history-repo, I see that it used GCC, not PCC. Where can I look at the history of x86 code generation development in PCC? Do I understand correctly that i386 code generation in PCC evolved in parallel with GCC, and at some point GCC was convinced to adopt the (less efficient) PCC calling convention by default? Did PCC prefer to do this stack adjustment for the invisible pointer on the callee side for some other platform, and the behavior was merely carried over to the i386 port? Thank you. Alexander

3 years, 3 months

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Re: [TUHS] Documenter's Workbench versions

by Douglas McIlroy

> The Documenter's Workbench is sort of the unsung hero > of Unix. It is why Unix exists, Unix was done to write patents and > troff and the Documenter's Workbench was all about that. My response along the following lines seems to have gone astray. The prime reason for Unix was the desire of Ken, Dennis, and Joe Ossanna to have a pleasant environment for software development. The fig leaf that got the nod from Multics-burned management was that an early use would be to develop a "stand-alone" word-processing system for use in typing pools and secretarial offices. Perhaps they had in mind "dedicated", as distinct from "stand-alone"; that's what eventuated in various cases, most notably in the legal/patent department and in the AT&T CEO's office. Both those systems were targets of opportunity, not foreseen from the start. When Unix was up and running on the PDP-11, Joe got wind of the legal department having installed a commercial word processor. He went to pitch Unix as an alternative and clinched a trial by promising to make roff able to number lines by tomorrow in order to fulfill a patent-office requirement that the commercial system did not support. Modems were installed so legal-department secretaries could try the Research machine. They liked it and Joe's superb customer service. Soon the legal department got a system of their own. Joe went on to create nroff and troff. Document preparation became a widespread use of Unix, but no stand-alone word-processing system was ever undertaken. Doug

3 years, 4 months

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"Applications for UnixWare" available online

by Greg 'groggy' Lehey

Decades ago (mid 1993) I produced a CD-ROM with free software for Novell's UnixWare entitled "Applications for UnixWare". This was at Novell's request, and they distributed the CDs at trade shows. There's nothing very special in the CD, but I recently received a request for it, so I put it up with a minimal description at http://www.lemis.com/grog/Software/Applications-for-UnixWare.php Feel free to copy it (with attribution). Greg -- Sent from my desktop computer. Finger grog(a)lemis.com for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft mail program reports problems, please read http://lemis.com/broken-MUA.php

3 years, 4 months

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Brenda Baker's Struct Memo

by Warren Toomey

All, I've just placed this document at https://www.tuhs.org/Archive/Documentation/TechReports/Baker_Struct/bsbstru… Many thanks to Doug for passing it on! Cheers, Warren ----- Forwarded message from Douglas McIlroy ----- Warren, Someone asked if Brenda Baker's original technical memorandum about struct is available. I scanned my copy and passed it on, secure in my belief that the Labs won't care since it is essentially the same as her journal publication. For the memo to be genuinely available, I'd like to send it to TUHS. With that in mind I redacted information about corporate organization and distribution channels. However the memo still bears the AT&T logo and the words "not for publication". Doug ----- End forwarded message -----

3 years, 4 months

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Re: [TUHS] Brenda Baker's Struct Memo

by Nelson H. F. Beebe

Thanks to Doug and Warren for getting Brenda Baker's memo on struct online at https://www.tuhs.org/Archive/Documentation/TechReports/Baker_Struct/bsbstru… She later published a formal article about that work in An Algorithm for Structuring Flowgraphs Journal of the Association for Computing Machinery 24(1) 98--120 January 1977 https://doi.org/10.1145/321992.321999 ------------------------------------------------------------------------------- - Nelson H. F. Beebe Tel: +1 801 581 5254 - - University of Utah FAX: +1 801 581 4148 - - Department of Mathematics, 110 LCB Internet e-mail: beebe(a)math.utah.edu - - 155 S 1400 E RM 233 beebe(a)acm.org beebe(a)computer.org - - Salt Lake City, UT 84112-0090, USA URL: http://www.math.utah.edu/~beebe/ - -------------------------------------------------------------------------------

3 years, 4 months

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Pipes and PRISM

by Paul Winalski

Last week there was a bit of discussion about the different shells that would eventually lead to srb writing the shell that took his name and the command syntax and semantics that most modern shells use today. Some of you may remember, VMS had a command interpreter called DCL (Digital Command language), part of an attempt to make command syntax uniform across DEC's different operating systems (TOPS-20 also used DCL). As DEC started to recognize the value of the Unix marketplace, a project was born in DEC's Commercial Languages and Tools group to bring the Unix Bourne shell to VMS and to sell it as a product they called DEC Shell. I had been part of that effort and one of the issues we had to solve is providing formal UNIX pipe semantics. They of course needed to somehow implement UNIX style process pipelines. VMS from the beginning has had an interprocess communications pseudo-device called the mailbox that can be written to and read from via the usual I/O mechanism (the QIO system service). A large problem with them is that it is not possible to detect the "broken pipe" condition with a mailbox and that feature deficiency made them unsuitable for use with DEC Shell. So the team had me write a new device driver, based closely on the mailbox driver, but that could detect broken pipes lines UNIX-style. Shortly after I finished the VMS pipe driver, the team at DECwest had started work on the MICA project, which was Dave Culter's proposed OS unification. Dave's team had developed a machine architecture called PRISM (Proposed RISC Machine) to be the VAX follow-on. For forward compatibility purposes, PRISM would have to support both Ultrix and VMS. Dave and team had already written a microkernel-based, lightweight OS for VAX called VAXeln that was intended for real-time applications. His new idea was to have a MACH-like microkernel OS which he called MICA and then to put three user mode personality modules on top of that: P.VMS, implementing the VMS system services and ABI P.Ultrix, implementing the Unix system calls and ABI P.TBD, a new OS API and ABI intended to supersede VMS So I wrote the attached "why pipes" memo to explain to Cutler's team why it was important to implement pipes natively in P.TBD if they wanted that OS to be a viable follow-on to VMS and Ultrix. In the end, Dick Sites's 64-bit RISC machine architecture proposal, which was called Alpha, won out over PRISM. Cutler and a bunch of his DECwest engineering team went off to Microsoft. Dave's idea of a microkernel-based OS with multiple personalities of course saw the light of day originally as NT OS/2, but because of the idea of multiple personalities, when Microsoft and IBM divorced Dave was able to quickly pivot to the now infamous Win32 personality, as what would be called Windows NT. It was also easy for Softway Systems to later complete the NT POSIX layer for their Interix product, which now a few generations later is called WSL by Microsoft. -Paul W.

3 years, 4 months

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Re: [TUHS] Memory on Lion's v6

by jnc＠mercury.lcs.mit.edu

> You made a comment that MINI-UNIX wasn't available outside of Bell... No, I didn't say that. What I _actually_ said was: "don't think they were in wide use outside Bell". Noel PS: Can I appeal to people to please take a few seconds of their time and trim messages they are replying to? Thank you.

3 years, 4 months

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Re: [TUHS] Memory on Lion's v6

by jnc＠mercury.lcs.mit.edu

> From: Andrew Hume > the actual configuration of Lions; PDP 11/40 was > 128 Kbytes of core memory > ... > but note that because ... of addressing weirdness (the top 8KB were > memory-mapped to I/O registers), Lions' PDP actually had 112KB of main > memory I think that '112KB' must be an error; the 8KB for the 'I/O page' (as DEC eventually named ir, long after the rest of the world had started using the term :-) were deducted from the _UNIBUS_ address space, meaning a UNIBUS -11 (the 'pure' UNIBUS -11's, i.e. other than the -11/70, -11/44, etc) could have a maximum of 248KB of main memory (which is on the UNIBUS). A pure UNIBUS -11 with 128KB of main memory (like Lions') has... 128KB of main memory. The 'small memory management model' -11's (like the /40, /60, /23, etc) can use at most 64KB of that _at any moment in time_ for user processes (i.e. directly accessible by the CPU, in 'user' mode). (The kernel on such machines is basically retricted to 56KB at any moment in time, since one 'segment/page' - the terminology changed over time - has to be dedicated to the I/O page: the memory management control registers are in that, so once the CPU can no longer 'see' them, it's stuck. Long, potentially interesting digression about, and ways to semi-work around that, elided, unless people want to hear it.) > From: Noel Chiappa > The -11/40 (as it was at first) that I had at LCS had, to start with, > I'm pretty sure, 3 MM11-L units .. - i.e. 48KB. I know this sounds > incredible, and I'm having a hard time believing it myself, wondering > if my memory is failing with age It is: # size /lib/c0 13440+2728+10390=26558 (63676) ('c1' takes 14848+6950+2088=23886, FWIW.) So 'my' -11/40 must have had more than 48KB. MINI-UNIX provides, on an -11/05 type machine with the maximum of 56KB of addressable main memory (if you plugged in 64KB worth, the /05 CPU couldn't 'see' the top 8KB of that), up to 32KB for a user process. So that will just hold the stock V6 C compiler. I'm not now sure how much memory my -11 _did_ have initially, but it's not important. Noel

3 years, 4 months

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Lorinda Cherry

by Brian Walden

I enjoy this dc(1) discussion. I am a daily dc user, and since my fisrt calculator was an HP-45 (circa 1973) RPN felt right. However I think dc pre-dates ALL HP calculators, since there was one in the 1st Edition written in assembly. I extened my version of dc (way before gnu existed) based on common buttons I used from HP calculators: CMD WHAT # comment, to new line ~ change sign of top of stack (CHS key) | 1/top of stack (1/x key) e push 99 digits of e (2.718..) on the stack @ push 99 digits of pi on the stack (looks like a circle) r reverse top of stack (x<>y key) I had been fascinated with pi stemimg from the Star Trek epsiode Wolf in the Fold where Spock uses it to usa all computing power "Computer, this is a Class A compulsory directive. Compute to the last digit the value of pi." "As we know, the value of pi is a transcendental figure without resolution. The computer banks will work on this problem to the exclusion of all else until we order it to stop." As it was supposed to be "arbitrary precision" here was my tool. So I wrote Machin formula in dc slowing increasing the scale and printing the results. In the orginal dc, yes the whole part was arbitrary, but the decimal part (scale) was limited to 99. Well that became a disappiontment. (this program is lost to time) So I decided to rewrite it but increasing pi as a whole numbers instead of increasing scale (ex. 31415, 314159, 3141592, ... etc) I still have that program which is simply this -- [sxln_1ll*dsllb*dszli2+dsi5li^*/+dsn4*lelzli239li^*/+dse-dlx!=Q]sQ 1[ddsb5/sn239/se1ddsisllQx4*pclb10*lPx]dsPx if you run it you'll notice the last 1 to 2 digits are wrong due to precision. The next problem became small memory. I still have thes saved output before it crashed at 1024 digits. No idea what specs of the machine it was run on anymore its really old -- 3141592653589793238462643383279502884197169399375105820974944592307816\ 4062862089986280348253421170679821480865132823066470938446095505822317\ 2535940812848111745028410270193852110555964462294895493038196442881097\ 5665933446128475648233786783165271201909145648566923460348610454326648\ 2133936072602491412737245870066063155881748815209209628292540917153643\ 6789259036001133053054882046652138414695194151160943305727036575959195\ 3092186117381932611793105118548074462379962749567351885752724891227938\ 1830119491298336733624406566430860213949463952247371907021798609437027\ 7053921717629317675238467481846766940513200056812714526356082778577134\ 2757789609173637178721468440901224953430146549585371050792279689258923\ 5420199561121290219608640344181598136297747713099605187072113499999983\ 7297804995105973173281609631859502445945534690830264252230825334468503\ 5261931188171010003137838752886587533208381420617177669147303598253490\ 4287554687311595628638823537875937519577818577805321712268066130019278\ 76611195909216420198938095257201065485862972 out of space: salloc all 8587356 rel 8587326 headmor 1 nbytes -28318 stk 71154 rd 125364 wt 125367 beg 125364 last 125367 83 11 0 30 IOT trap - core dumped But I was much happier with that. On a side note: programming dc is hard. There was no comment character. And it's a pain to read, and it's a pain to debug. When I discovered the Chudnovsky algorithm for pi, of course I implemented it in dc -- [0ksslk3^16lkd12+sk*-lm*lhd1+sh3^/smlx_262537412640768000*sxll545140134+dsllm*lxlnk/ls+dls!=P]sP 7sn[6sk1ddshsxsm13591409dsllPx10005v426880*ls/K3-k1/pcln14+snlMx]dsMx At 99 digits of scale it ran out in 7 rounds, but now with that limitation removed and large memeories it just goes on and on..... -Brian PS: Thanks for the fast OpenBSD version of dc, Otto. Otto Moerbeek wrote: > On Thu, Feb 17, 2022 at 01:44:07PM -0800, Bakul Shah wrote: > > > On Feb 17, 2022, at 1:18 PM, Dave Horsfall <dave at horsfall.org> wrote: > > > > > > On Thu, 17 Feb 2022, Tom Ivar Helbekkmo via TUHS wrote: > > > > > >> Watching the prime number generator (from the Wikipedia page on dc) > > >> running on the 11/23 is much more entertaining than doing it on the > > >> modern workstation I'm typing this on: > > >> > > >> 2p3p[dl!d2+s!%0=@l!l^!<#]s#[s/0ds^]s@[p]s&[ddvs^3s!l#x0<&2+l.x]ds.x > > > > > > Wow... About 10s on my old MacBook Pro, and I gave up on my ancient > > > FreeBSD box. > > > > That may be because FreeBSD continues computing primes while the MacOS > > dc gives up after a while! > > > > freebsd (ryzen 2700 3.2Ghz): # note: I interrupted dc after a while > > $ command time dc <<< '2p3p[dl!d2+s!%0=@l!l^!<#]s#[s/0ds^]s@[p]s&[ddvs^3s!l#x0<&2+l.x]ds.x' > xxx > > ^C 11.93 real 11.79 user 0.13 sys > > $ wc xxx > > 47161 47161 319109 xxx > > $ size `which dc` > > text data bss dec hex filename > > 238159 2784 11072 252015 0x3d86f /usr/bin/dc > > > > MacOS (m1 pro, prob. 2Ghz) > > $ command time dc <<< '2p3p[dl!d2+s!%0=@l!l^!<#]s#[s/0ds^]s@[p]s&[ddvs^3s!l#x0<&2+l.x]ds.x' > xxx > > time: command terminated abnormally > > 1.00 real 0.98 user 0.01 sys > > [2] 37135 segmentation fault command time dc <<< > xxx > > $ wc xxx > > 7342 7342 42626 xxx > > $ size `which dc` > > __TEXT __DATA __OBJC others dec hex > > 32768 16384 0 4295016448 4295065600 100018000 > > > > MacOS uses the GNU implementation which has a long standing issue with > deep recursion. It even cannot handle the tail recursive calls used > here and will run out of its stack. > > -Otto

3 years, 4 months

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ok-labs.com is not OK

by Dave Horsfall

Someone on one of these lists seems to be at ok-labs.com; well... aneurin% host ok-labs.com ;; connection timed out; no servers could be reached aneurin% Houston, we have a problem... Could whoever is responsible please sprinkle some fairy dust somewhere? Thanks. -- Dave

3 years, 4 months

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Memory on Lion's v6

by Will Senn

Does anybody know how much memory was configured on the PDP-11 that Lion's used for the commentary system. Here's what the book says about the system: ; from lions, page 1 ; The code selection presumes a "model" system consisting of: ; PDP11/40 processor; ; RK05 disk drives; ; LP11 line printer; ; PC11 paper tape reader/punch; ; KL11 terminal interface. I usually add the mag tape, too ; TM10 magnetic tape - not in lions, but super handy It seems like he must have had an MMU and 128k memory, but I don't know. I'm hoping y'all remember, know, or can otherwise divine the correct value. I've run with no MMU - crash on boot. I've also run with less memory, but then cc won't build mkconf, when I have the TM10 enabled kernel loaded. As a reminder, his book was published in 1977. Thanks, Will

3 years, 4 months

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Re: [TUHS] Memory on Lion's v6

by jnc＠mercury.lcs.mit.edu

> From: Will Senn > Does anybody know how much memory was configured on the PDP-11 that > Lion's used for the commentary system. Here's what the book says about > the system: > .. > ; PDP11/40 processor; > ... > It seems like he must have had an MMU V6 absolutely requires an MMU; the need for it is all throughout basic attributes of the system - e.g. user processes start their address space at 0. (BTW, there are V6 descendants, MINI-UNIX: http://gunkies.org/wiki/MINI-UNIX and LSX, which don't use/need an MMU, and run on -11 models without memory managament, such as -11/05's, but I don't think they were in wide use outside Bell.) > and 128k memory The -11/40, as originally released, only supported the MM11-L, which came in multiples of 16KB (for a 3-board set). Use of the later MM11-U (32KB units) required a new main power harness, which only came in on higher-serial-numbered -11/40's. The -11/40 (as it was at first) that I had at LCS had, to start with, I'm pretty sure, 3 MM11-L units (i.e. one MM11-L backplane full) - i.e. 48KB. I know this sounds incredible, and I'm having a hard time believing it myself, wondering if my memory is failing with age; but it definitely had extraordinarily little. I just looked on my V6 (running in a simulator), and it appears that by trimming all parameters (e.g. number of disk buffers) to the absolute bone, the kernel could be trimmed to about 36KB. (I haven't actually tried it, since I don't feel like recompiling all the kernel modules, but one can estimate it - take the current system size [44KB], delete 10 buffers @ .5KB gives 39KB, etc, etc.) That would allow a maximum user process of 12KB on a 48KB machine - and MINI-UNIX, which runs basically stock V6 user code, can manage with user processes that small. I see Andrew's email which reports that the Lions machine had more main memory, 128KB (maybe 4 MM11-U's - two MM11-U backplanes full); that woould have made their life a lot easier. Noel

3 years, 4 months

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Re: [TUHS] run commands at login in v6 and stty

by Douglas McIlroy

> The X11 tree was a heavily ifdef-ed. And it needed to be, I don't have > an answer as to how you would reuse all that code on different hardware > in a better way. Plan 9 did it with #include. The name of the included file was the same for every architecture. Only the search path for include files changed. Done with care, this eliminates the typical upfront #ifdefs.that define constants and set flags. Other preprocessor conditionals can usually be replaced by a regular if, letting the compiler optimize away the unwanted alternative. This makes conditionals obey the scope rules of C. Doug

3 years, 4 months

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Re: [TUHS] run commands at login in v6 and stty

by Brian Walden

6th Edition used the Thompson shell as /bin/sh. I don't think it had those capabilities. Sometimes you could find an early version of the Bourne shell in /bin/nsh (new shell) in v6. The 7th Edition made the Bourne shell /bin/sh. And there sometimes you could find the Thompson shell in /bin/osh (old shell). Will Senn wrote: > Login commands question: > > I'm sure it's simple, but I can't figure it out. How do I get something > to run at login in v6? Right now, I use ed to create a file 'setprof' > that contains: > > stty erase[space][backspace][return] > stty nl0 cr0 > > Then after logging in: > > sh setprof > > It works, but, it is pretty clunky. > > stty question: > > So, I looked at stty.c and it looks like the following should work, if > the terminal is sending ^H for backspace: > > #define BS0 0 > #define BS1 0100000 > > modes[] > ... > "bs0", > BS0, BS1, > > "bs1", > BS1, BS1, > > > but: > > stty bs0 > or > stty bs1 > > don't result in proper backspace handling.. > > but: > > stty[space][^h][return] > > > works... > > Thoughts?

3 years, 4 months

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run commands at login in v6 and stty

by Will Senn

Login commands question: I'm sure it's simple, but I can't figure it out. How do I get something to run at login in v6? Right now, I use ed to create a file 'setprof' that contains: stty erase[space][backspace][return] stty nl0 cr0 Then after logging in: sh setprof It works, but, it is pretty clunky. stty question: So, I looked at stty.c and it looks like the following should work, if the terminal is sending ^H for backspace: #define BS0 0 #define BS1 0100000 modes[] ... "bs0", BS0, BS1, "bs1", BS1, BS1, but: stty bs0 or stty bs1 don't result in proper backspace handling.. but: stty[space][^h][return] works... Thoughts?

3 years, 4 months

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Re: [TUHS] run commands at login in v6 and stty

by jnc＠mercury.lcs.mit.edu

> From: Clem Cole > what I don't remember was it in v5 Your memory is going! :-) We discussed this recently (well, recently in _our_ timescale :-); it's built into in 'cc' in V5: https://minnie.tuhs.org/cgi-bin/utree.pl?file=V5/usr/source/s1/cc.c see "expand(file)". Noel

3 years, 4 months

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Re: [TUHS] CSR in V6

by jnc＠mercury.lcs.mit.edu

> From: Will Senn > My question is - how did y'all run things - with CSR zero and no kernel > messages ... or with CSR non-zero and kernel messages. On the -11/45 V6+ at MIT, we didn't have a printing terminal on the console, just a VT52. We had a tool at MIT called 'dmesg': http://ana-3.lcs.mit.edu/~jnc/tech/unix/man8/dmesg.8 which made up for that a bit. We normally ran with the CSR set to 173030 - the 'boot in single-user' setting. That's because at one point the machine was in the 9th floor machine room, but the console VT52 was on the 5th floor (where our offices were - the famous print of the GE-645 Multics was on the hallway wall outside mine :-), and I'd added a 'reboot()' system call (nothing fancy, it just jumped to the bootstrap ROM), so we could reboot the machine without going up in the elevator (not if it had crashed, of course). Later on, after we'd done with kernel hacking (adding a network interface, and IP), and the machine stayed up for long periods, we moved the console up next to the machine (since if it crashed, you had to use the front panel to restart it, so you had to be up there anyway); we stayed with the default CSR setting, though. (If it panic'd, you could see the reason why when you went to reboot it.) > Oh, BTW, I know I've seen this noted elsewhere, but I can't remember > where. Maybe at: https://gunkies.org/wiki/UNIX_Sixth_Edition#Distros which discusses it? Noel

3 years, 4 months

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CSR in V6

by Will Senn

I noticed in v6 source that putch in prf.c - the system kernel printf's character routine, only prints to the console if the Console Switch Register is non-zero. My question is - how did y'all run things - with CSR zero and no kernel messages (seems dangerous to me, being naive and all) or with CSR non-zero and kernel messages. On my FreeBSD instance, I value the messages that show up on console as they've alerted me to big problems in the past, but on my Mac, not as much (sure you can run Console and see them, but they aren't immediate). Oh, BTW, I know I've seen this noted elsewhere, but I can't remember where. Dennis's v6 doesn't have the Western Electric message: mem = 435 RESTRICTED RIGHTS Use, duplication or disclosure is subject to restrictions stated in Contract with Western Electric Company, Inc. It was a bit of a head scratcher as I was trying to read from the Dennis version of the distro on my mac while running Wellsch's tape on simh. I spent quite a while spinning my wheels looking for "Western" in the files to no avail. I thought something was screwy with the files or my mac.

3 years, 4 months

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Lions v6 source code pdf

by Will Senn

All, I got sick of poring over my Peer-to-Peer communications version of Lion's commentary - trying to read it while digging around in v6 was getting annoying. Of course, if you don't already own, rush out and by a copy. It's great stuff. Anyhow, the problem is that it's perfect bound, landscape and it's not searchable. Hunting around the internet, I found pdfs that were searchable, but they were based on v7 being back-engineered to v6 code. So, I located a decent source of electronically readable Lion's source at https://warsus.github.io/lions-/ and off I went. I took the code and did a bit (quite a bit) of tweakage on it to get it formatted in pdf, and created a version in letter format that I find pretty useful. It can be read from a printout while messing around in v6. I've done some proofing, but I don't claim it's perfect. If you find any issues with it, let me know and I'll try to fix them (thanks, Clem for early suggestions). Here's what's in the letter sized pdf: Tweaked Cover Page Improved Table of Contents Lion's version of V6 Source Code Appendices Source File Sheets Alphabetical List Source File Locations in Running V6 System What isn't in the pdf: Original Forewords, Prefaces, or Letters (not needed for coding) Symbol Lists, Cross references, or Indexes (beyond my skills at the moment) All in all, I have found it quite readable and useful for my own work. I don't claim any ownership or contribution, other than in improving the readability of the work for modern readers. If the cross reference thing kills you, just use gnu ctags on the source directories and ctags -x for the line numbers. Here's the link to the posting: http://decuser.blogspot.com/2022/02/tweaked-version-of-lions-v6-source-code… - will

3 years, 4 months

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Lorinda Cherry

by Douglas McIlroy

Lorinda Cherry, a long-time member of the original Unix Lab died recently. Here is a slightly edited reminiscence that I sent to the president of the National Center for Women and Information Technology in 2018 when they honored her with their Pioneer in Tech award. As Lorinda Cherry's longtime colleague at Bell Labs, I was very pleased to hear she has been chosen for the NCWIT Pioneer Award. At the risk of telling you things you already know, I offer some remarks about her career. I will mainly speak of things I saw at first hand when our offices were two doors apart, from the early '70s through 1994, when Lorinda left Bell Labs in the AT&T/Lucent split. Most of the work I describe broke new ground in computing; "pioneer" is an apt term. Lorinda, like many women (including my own mother and my wife), had to fight the system to be allowed to study math and science in college. She was hired by Visual and Acoustics Research at Bell Labs as a TA--the typical fate of women graduates, while their male counterparts were hired as full members of technical staff. It would take another decade for that unequal treatment to be rectified. Even then, one year she received a statement of benefits that explained what her wife would receive upon her death. When Lorinda called HR to confirm that they meant spouse, they said no, and demanded that the notice be returned. (She declined.) It seemed that husbands would not get equal treatment until AT&T lost a current court case. The loss was a foregone conclusion; still AT&T preferred to pay lawyers rather than widowers, and fought it to the bitter end. Lorinda moved to my department in Computing Science when the Unix operating system was in its infancy. Initially she collaborated with Ken Knowlton on nascent graphics applications: Beflix, a system for producing artistically pixillated films, and an early program for rendering ball-and-stick molecular models. She then joined the (self-organized) Unix team, collaborating on several applications with Bob Morris. First came "dc", an unlimited-precision desk calculator, which is still a Unix staple 45 years on. Building on dc, she would later make "bc", which made unlimited precision available in familiar programming-language notation and became the interface of choice to dc. Then came "form" and "fed", nominally a form-letter generator and editor. In fact they were more of a personal memory bank, a step towards Vannevar Bush's famous Memex concept--an interesting try that didn't pay off at that scale. Memex had to sleep two more decades before mutating into the Worldwide Web. Lorinda had a hand in "typo", too, a Morris invention that found gross spelling mistakes by statistical analysis. Sorting the words of a document by the similarity of their trigrams to those in the rest of the document tended to bring typos to the front of the list. This worked remarkably well and gained popularity as a spell-checker until a much less interesting program backed by a big dictionary took over. Taken together, these initial forays foretold a productive computer science career centered around graphics, little languages, and text processing. By connecting a phototypesetter as an output device for Unix, Joe Ossanna initiated a revolution in document preparation. The new resource prompted a flurry of disparate looking documents until Mike Lesk brought order to the chaos by creating a macro package to produce a useful standard paper format. Taking over from Lesk, Lorinda observed the difficulty of typesetting the mathematics (which the printing industry counted as "penalty copy") that occurred in many research papers, and set out to simplify the task of rendering mathematical formulas, Brian Kernighan soon joined her effort. The result was "eqn", which built on the way people read formulas aloud to make a quite intuitive language for describing display formulas. Having pioneered a pattern that has been adopted throughout the industry, eqn is still in use forty years later. Lorinda also wrote an interpreter to render phototypesetter copy on a cathode-ray terminal. This allowed one to see typeset documents without the hassle of exposing and developing film. Though everyone has similar technology at their fingertips today, this was genuinely pioneering work at the time. You are certainly aware of Writers Workbench, which gained national publicity, including Lorinda's appearance on the Today Show. It all began as a one-woman skunk-works project. Noticing the very slow progress in natuaral-language processing, she identified a useful subtask that could be carved out of the larger problem: identifying parts of speech. Using a vocabulary of function words (articles, pronouns, prepositions and conjunctions) and rules of inflection, she was able to classify parts of speech in running text with impressive accuracy. When Rutgers professor William Vesterman proposed a style-assessing program, with measures such as the frequencies of adjectives, subordinate clauses, or compound sentences, Lorinda was able to harness her "parts" program to implement the idea in a couple of weeks. Subsequently Nina MacDonald, with Lorinda's support, incorporated it into a larger suite that checked and made suggestions about other stylistic issues such as cliches, malapropisms, and redundancy. Another aspect of text processing that Lorinda addressed was topic identification. Terms (often word pairs) that occur with abnormal frequency are likely to describe the topic at hand. She used this idea to construct first drafts of indexes. One in-house application was to the Unix manual, which up until that time had only a table of contents, but no index. This was a huge boon for a document so packed with detail. In her final years at Bell Labs, Lorinda teamed up with AT&T trouble-call centers to analyze the call transcripts that attendants recorded on the fly--very sketchy prose, replete with ad-hoc contractions and misspellings. The purpose was to identify systemic problems that would not be obvious from transcripts considered individually. When an unusual topic appeared at the same time in multiple transcripts, those transcripts were singled out for further study. The scheme worked and led to early detection of system anomalies. In one case, it led AT&T to suspend publication of a house organ that rubbed customers the wrong way. Lorinda was not cut from the same mold as most of her colleagues. First she was a woman, which meant she faced special obstacles. Then, while there were several pilots among us, there was only one shower of dogs and only one car racer--moreover one who became a regional exec of the Sports Car Club of America. For years she organized and officiated at races as well as participating. Lorinda was always determined, but never pushy. The determination shows in her success in text analysis, which involves much sheer grit--there are no theoretical shortcuts in this subject. She published little, but did a lot. I am glad to see her honored. Doug McIlroy

3 years, 4 months

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Re: [TUHS] v7 source code for sh

by Brian Walden

The one I remember using in the 80s was called "fep" written by Kazumasa Utashiro of Software Research Associates. It was probbaly posetd posted to comp.sources.unix usenet group. -Brian Chet Ramey wrote: > On 2/20/22 4:19 PM, Lyndon Nerenberg (VE7TFX/VE6BBM) wrote: > > Chet Ramey writes: > > > >> It always seemed like it would have been just the thing to implement as a > >> tty streams module, but research Unix went in a different direction. > > > > I'm really surprised nobody has implemented a basic readline as a > > tty line discipline by now. I was poking around the OpenBSD NMEA > > line discipline code a few weeks ago and thinking it shouldn't be > > that hard to do. > > It's not that hard. The complexity is in how sophisticated you want to get > with redisplay and whether you want to allow user-specified key bindings. > > > Did anyone think about doing this in the past? If yes, what made you > > decide against doing it? (Or a streams implementation, for that matter.) > > There have been several implementations (I never did one). I suspect that > the people who were in a position to integrate that functionality into > distributed kernels were not supportive, or the code didn't get to them > at the right time. > -- > ``The lyf so short, the craft so long to lerne.'' - Chaucer > ``Ars longa, vita brevis'' - Hippocrates > Chet Ramey, UTech, CWRU chet(a)case.edu http://tiswww.cwru.edu/~chet/

3 years, 4 months

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Re: [TUHS] v7 source code for sh

by Bakul Shah

On Feb 19, 2022, at 8:11 AM, Clem Cole <clemc(a)ccc.com> wrote: > > > On Sat, Feb 19, 2022 at 11:04 AM Steve Nickolas <usotsuki(a)buric.co> wrote: >> Apparently Bourne was heavily into ALGOL, > That's sort of an understatement. I believe that when he was at Cambridge, he was one of the people that helped to take the Algol-X proposal and turned it into the Algol-68 definition. I also believe he worked on their famous implementation of same. Some of you may be interested in this “A history of Algol68” paper: https://dl.acm.org/doi/pdf/10.1145/234286.1057810 The author, Charles H Lindsey, still occasionally posts on comp.lang.misc about Algol68. Among other things Bourne was a coauthor of Algol68C, a portable implementation of Algol68.

3 years, 4 months

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Re: [TUHS] v7 source code for sh

by norman＠oclsc.org

Rob Pike: I did the same to adb, which turned out to have a really good debugger hidden under a few serious bugs of its own, which I fixed. ===== Memories. Was it you who replaced ptrace with /proc in adb, or did I do that? I do remember I was the one who took ptrace out of sdb (which a few 1127-ers, or perhaps 112-ers on alice and rabbit still used). After which I removed ptrace from the kernel, and from the copy of the V8 manual in the UNIX room. Conveniently ptrace occupied two facing pages; I glued them together. I also later did some work to try to isolate the target-dependent parts of adb and to make them work in host-independent ways--e.g. assembling ints byte-by-byte rather than assuming byte order--to make it easier to make a cross adb, e.g. to examine PDP-11 or 68K core dumps on a VAX. I miss adb; maybe it's time to revive it, though these days I'd be tempted to rewrite it in Python so I could just load the right module at runtime to pick the desired target. Norman Wilson Toronto ON

3 years, 4 months

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Re: [TUHS] v7 source code for sh

by Rudi Blom

Second half of the 1980-tish when the computer division of Philips Electronics started on their own Motorola M68010 / UNIX System V.3 (don't remember for sure I'm afraid) they used a syntax.h with macros similar to mac.h. Only I understand it's more Pascal like. Appended the 1987 version I found in my archive. Cheers, rubl -- The more I learn the better I understand I know nothing.

3 years, 4 months

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v7 source code for sh

by Will Senn

I have been poring through the v7 source code lately, and came across an oddity I would like to know more about. Specifically, in sh. The code for sh is c, but it makes *extensive* use of of macros, for example: /usr/src/cmd/sh/word.c ... WHILE (c=nextc(0), space(c)) DONE ... The macros for sh are defined in mac.h: /usr/src/cmd/sh/mac.h ... #define BEGIN { #define END } #define SWITCH switch( #define IN ){ #define ENDSW } #define FOR for( #define WHILE while( #define DO ){ #define OD ;} #define REP do{ #define PER }while( #define DONE ); ... I can read the resultant code through the lens of my experience coding c, but I'm curious why the macros and how this came about? In v6, the sh source is straight up c. Is there a story behind it worth knowing? Thanks, Will

3 years, 4 months

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Ping! I love that duck!

by Rich Morin

I was just reminded of this and thought others might enjoy reading it... Customer Review https://www.amazon.com/gp/customer-reviews/R2VDKZ4X1F992Q/ > PING! The magic duck! > Using deft allegory, the authors have provided an insightful and intuitive explanation of one of Unix's most venerable networking utilities. Even more stunning is that they were clearly working with a very early beta of the program, as their book first appeared in 1933, years (decades!) before the operating system and network infrastructure were finalized. ... -r

3 years, 4 months

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Re: [TUHS] Lorinda Cherry

by norman＠oclsc.org

Perhaps the best irrefutable source for Lorinda's contribution to dc is that cited by https://en.wikipedia.org/wiki/Lorinda_Cherry? It is, by the way, Doug's A Research UNIX Reader. Those who subscribe to this list and haven't read it ought to do so; it's full of tidbits of history. Norman Wilson Toronto ON

3 years, 4 months

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7th Edition C Reference Manual and UNIX Programming - First Edition

by Will Senn

All, 1. I have a physical copy of the V7 UPM published by Holt, Rinehart and Winston (HRW) from 1983 (2 volume phone book). In it, there is a C Reference Manual (pp. 247-277, reprinted with minor changes from the first C book by K&R and including a Recent Changes to C addendum). I also have a PDF that was supposedly created from sources that has a C Reference Manual in it, but, in /usr/doc/cman, there's an inscription that reads, "Sorry, but for copyright reasons, the source for the C Reference Manual is not distributed." and the one in the pdf appears to be identical to the one in the V6 UPM (which I have a print-on-demand version of). Are the *roff sources (or a clean PDF) available for the reprint? I have located a PDF copy of the HRW edition, but it's got the usual deficiencies of being a scanned copy. 2. In same manual, there is an article entitled, UNIX Programming -- Second Edition by K&R. Where is the first edition located? It isn't in the V6 UPM. Regards, Will

3 years, 4 months

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Lions' commentary on PCC pass1?

by hveit01＠web.de

3 years, 4 months

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Lorinda Cherry

by John P. Linderman

I got his from a friend today (15 February): =========== I'm sorry to report that Lorinda passed away a few days ago. I got a call from her sister today. Apparently the dog walker hadn't seen her for a few days and called the police. The police entered the house and found her there. Her sister says they are assuming either a heart attack or a stroke.

3 years, 4 months

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unexported software for local use for v7

by Will Senn

A week or so after spending an entire day meticulously mapping manpages from version 0 to version 7, I came across Doug's combined table of contents. I love recreating the wheel <<shakes head, ruefully>>, only saving grace is that the geniuses who came before, in this case Doug, had the same idea :). In it, he mentions an addendum for v7 that has pages for unexported software for local use: apl, cflow, cpio, cref, and a slew of other usefull commands get mentioned. By unexported, I'm gathering this means not included on the distro tapes -- I certainly don't see them in my installed system. Were they distributed at all, or just used internally at Bell, or what? Are there extant copies around? To be clear, I'm talking about the unexported versions, not later versions that might be fitted onto v7. Oh, and a bonus question, why weren't they exported. Will

3 years, 4 months

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ratfor vibe

by Will Senn

All, I have been doing some language exploration in v7/4.3bsd and came across Software Tools (not the pascal version). It's written using ratfor, which I had seen in the v7 UPM. I fired up v7 and tried my hand at the first example: # copy - copy input characters to output integer getc integer c while(getc(c) != EOF) call putc(c) stop end The first thing I noticed was that it read more like C than Fortran (I know C quite well, Fortran just a smidge)... awesome, right? So I ran the preprocessor on it and got the following f77 code: c copy - copy input characters to output integer getc integer c c while 23000 if(.not.(getc(c) .ne. eof))goto 23001 call putc(c) goto 23000 c endwhile 23001 continue stop end Cool. The way it translated the EOF test is weird, but ok. Trying to compile it results in complaints about missing getc and putc: $ f77 copy.f copy.f: MAIN: Undefined: _getc_ _putc_ _end Ah well, no worries. I know that they're in the c lib, but don't about fortran libs... Meanwhile, over on 4.3BSD, it compiles without issue. But running it is no joy: $ ./a.out This is a test $ I remembered that the authors mentioned something about EOF, so I tweaked the code (changed EOF to -1) and rebuilt/reran: $ ./a.out This is a test This is a test $ Fascinating. Dunno why no complaints from F77 about the undefined EOF (or maybe mis-defined), but hey, it works and it's fun. I'm curious how much ratfor was used in bell labs and other locations running v6, v7, and the BSD's. When I first came across it, I was under the impression that it was a wrapper to make f66 bearable, but the manpage says it's best used with f77, so that's not quite right. As someone coming from c, I totally appreciate what it does to make the control structures I know and love available, but that wasn't the case back then, was it? C was pretty new... Was it just a temporary fix to a problem that just went away, or is there tons of ratfor out there in the wild that I just haven't seen? I found ratfor77 and it runs just fine on my mac with a few tweaks, so it's not dead: ratfor77 -C copy.r | tee copy.f C Output from Public domain Ratfor, version 1.0 C copy - copy input characters to output integer getc integer c 23000 if(getc(c) .ne. eof)then call putc(c) goto 23000 endif 23001 continue stop end What's the story? Oh, and in v6 it looks like it was rc - ratfor compiler, which is not present in v7 or 4.3BSD - is there a backstory there, too? Will

3 years, 4 months

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Looking back to 1981 - what pascal was popular on what unix?

by Will Senn

I'm reading in, Kernighan & Plauger's 1981 edition of Software Tools in Pascal and in the book, the author's mention Bill Joy's Pascal and Andy Tanenbaum's as being rock solid. So, a few related questions: 1. What edition of UNIX were they likely to be using? 2. What versions of "Standard Pascal" were in vogue on UNIX at the time (1981)? 3. What combinations of UNIX/Pascal were popular? Thanks, Will

3 years, 5 months

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BSD 4.1, 4.1x, Quasijarus, and 4.3x

by Will Senn

All, I did my research on this, but it's still a bit fuzzy (why is it that people's memories from 40 years ago are so malleable?). 1. What are y'all's recollections regarding BSD 4.1's releases, vis a vis the VAX. In McKusick's piece, Twenty Years of Berkeley Unix, I get one perspective, and from Sokolov's Quasijarus project, I get quite another. In terms of popularity and in terms of stable performance, what say you? Was 4.1 that much better than 4BSD? Was 4.1as obsolete immediately as McKusick says? 4.1b sounds good with FFS, was it? 4.1c's the last pre 4.2 release, but it sounds like it was nearly a beta version of 4.2... 2. Sokolov implies that the CSRG mission started going off the rails with the 4.3/4.3BSD-Tahoe and it all went pear shaped with the 4.3-Reno release, and that Quasijarus puts the mission back on track, is that so? 3. I've gotten BSD 4.2 and BSD 4.3 releases built from tape and working very well. I just can't decide whether to go back to one of the 4.x releases (hence question 1), or go get Quasijarus0c - thoughts on why one might be more interesting than another? 4. Is Quasijarus0c end of the line for VAX 4.xBSD? Why does tuhs only have Quasijarus0 and 0a, was there something wrong with 0b and 0c? 5. Has anyone unearthed an original 4.1 tape, or is Haertel's reconstruction of the 1981 tape 1 release as close as it gets? Later, Will

3 years, 5 months

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1994 One-minute Video for the UNIX 25th Birthday Party

by Brantley Coile

https://www.youtube.com/watch?v=EmcSpzpYnRk

3 years, 5 months

1
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Got kicked off list due to DNS Issues

by Justin Andrusk

Back in September I was having serious DNS issues with my MX records. Finally was able to move to a new DNS provider. Could someone add me (jra(a)andrusk.com) back to the mailing list? Thanks, Justin Sent from ProtonMail mobile

3 years, 5 months

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calendar events

by norman＠oclsc.org

Whose birthday is it, Ken? Norman Wilson Toronto ON

3 years, 5 months

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CSRG at berkeley

by ron minnich

the discussion of why the CSRG disbanded in 1995 has come up elsewhere. My memory is that the reason was pretty simple: DARPA ended their funding at that time. Hoping for corrections to my memory :-)

3 years, 5 months

5
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Re: [TUHS] ratfor vibe

by jnc＠mercury.lcs.mit.edu

> From: Clem Cole > So by the late 70s/early 80s, [except for MIT where LISP/Scheme reigned] Not quite. The picture is complicated, because outside the EECS department, they all did their own thing - e.g. in the mid-70's I took a programming intro couse in the Civil Engineering department which used Fortran. But in EECS, in the mid-70's, their intro programming course used assembler (PDP-11), Algol, and LISP - very roughly, a third of the time in each. Later on, I think it used CLU (hey, that was MIT-grown :-). I think Scheme was used later. In both of these cases, I have no idea if it was _only_ CLU/Scheme, or if they did part of it in other languages. Noel

3 years, 5 months

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FYI: Internet Old Farts Club

by Rich Morin

Some of the folks here might like this FB group... Internet Old Farts Club https://www.facebook.com/groups/internetoldfarts/ > This group is for self-declared Internet Old Farts, who want to discuss any aspect of the the Internet or its history. People in this group had their bits walk up hill both ways. > Welcome to the Internet Old Farts group. The purpose of this group is both social and technical. Feel free to revisit the past, explore the future, grouse about technical problems that you or others created. Feel free to self-aggrandize, complain about your least favorite standards organization or its politics, and how those young whippersnappers are running the show today. By participating in this group you are admitting or proclaiming that you are indeed an Internet Old Fart. Perhaps we should give a prize for the youngest and oldest Old Fart. -r

3 years, 5 months

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Ritchie/Thompson Unix Time-Sharing System in Classic Papers

by Nelson H. F. Beebe

There is a new book from MIT Press, edited by Harry Lewis, with a collection of classic papers in computer science, among them 37: The Unix Time-Sharing System (1974) Dennis Ritchie, Kenneth Thompson DOI: https://doi.org/10.7551/mitpress/12274.003.0039 The book Web site is at https://direct.mit.edu/books/book/5003/Ideas-That-Created-the-FutureClassic… ------------------------------------------------------------------------------- - Nelson H. F. Beebe Tel: +1 801 581 5254 - - University of Utah FAX: +1 801 581 4148 - - Department of Mathematics, 110 LCB Internet e-mail: beebe(a)math.utah.edu - - 155 S 1400 E RM 233 beebe(a)acm.org beebe(a)computer.org - - Salt Lake City, UT 84112-0090, USA URL: http://www.math.utah.edu/~beebe/ - -------------------------------------------------------------------------------

3 years, 5 months

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Ratfor s

by Will Senn

Has anyone seen Fraser's original ratfor source for the s editor for unix on the PDP-11. It was a screen editor front-end built on top of Software Tools's edit. I've seen a c version, but I'm interested in the 375 line version :). Will Sent from my iPhone

3 years, 5 months

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Compilation "vs" byte-code interpretation, was Re: Looking back to 1981 - what pascal was popular on what unix?

by silas poulson

Resending this as realised accidentally replied off list Silas On 30 Jan 2022, at 18:39, silas poulson <silas8642(a)hotmail.co.uk<mailto:silas8642@hotmail.co.uk>> wrote: On 30 Jan 2022, at 18:07, Dan Stromberg <drsalists(a)gmail.com<mailto:drsalists@gmail.com>> wrote: And is Java? They both have a byte code interpreter. My understanding is Java is both a compiled and interpreted language - with javac compiling java code to byte code and then JVM interpreting and executing the byte code. And then there's the CPython implementation of Python. <snip> Granted, it has an implicit, cached compilation step, but is it less compiled for that? I would so no - in my mind compiling analyses the entire source and then translates it whilst interpreters only explore a single line or expression. Simply because the compilation happens only Just In Time, doesn’t make it any less of a compilation step. Hope that helps, Silas

3 years, 5 months

1
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One more arch 4.4BSD binary set, luna68k on nono OMRON LUNA emulator

by MOCHIDA Shuji

One of architechture supported by 4.4BSD, luna68k's compiled binary is now available. http://www.netside.co.jp/~mochid/comp/bsd44-build/ luna68k is OMRON LUNA, m68k cpu workstation. This binary set works on "nono" emulator software. http://www.pastel-flower.jp/~isaki/nono/ It's author, Isaki-san have done some minor modification for 4.4BSD, binary set for luna68k run rather well. OMRON, already dropped thier workstation products. LUNA-I, LUNA-II equipped with m68k, same CPU as CSRG's main target arch hp300. So userland programs may binary compatible. -mochid

3 years, 5 months

1
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4.3 BSD network name resolution

by Will Senn

I'm working through 4.3BSD setup and configuration and came across this: "There is no equivalent service for network names yet. The full host and network name databases are normally derived from a file retrieved from Internet Network Information Center at SRI... use gettable to retrieve the NIC host database and htable to convert it to the format used by the libraries." Does this mean I should expect functionality like resolv.conf and ping yahoo.com not to work in 4.3, or by some miracle is gettable still a functional system? Will Sent from my iPhone

3 years, 5 months

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Re: [TUHS] FYI: Internet Old Farts Club

by norman＠oclsc.org

I'm too much of an old fart to use FaceBook. a Norman Wilson Toronto ON @oclsc on twitter

3 years, 5 months

2
1
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Latest release of retro-fuse

by Jay Logue

Hi all, I've been hard at work on my retro-fuse project over the past few months, and so I thought I'd update the list with my progress. I have just released version 7 of retro-fuse on github (https://github.com/jaylogue/retro-fuse) This version adds support for initializing and mounting 2.9 and 2.11BSD filesystems on modern systems. It also includes fixes for a number of bugs in v6 and v7 support. Beyond the work on 2.11 support, I also spent a significant amount of time building an automated test framework. I'm a pretty big fan of automated testing. So I'm happy to say that the project now includes a series of tests verifying basic file I/O functionality as seen from the modern system. While not exhaustive (because filesystem testing is /hard/) the new tests give me reasonable confidence that things are behaving as they should. Additionally (in what was perhaps the most fun part of the project to date) I have also created tests to verify the integrity of the generated filesystems as seen from the historical systems. In particular, for each of the supported Unix versions I've built tests that: launch the os under simulation (simh), mount the generated filesystems, verify the filesystems using the original integrity check tools (icheck/fsck), and enumerate and compare the filesystem contents to that generated on the modern system. As you might imagine, this involved a lot of learning--from how to build size-reduced system images from the original distribution tapes, to how to implement a modern POSIX cksum command with old dev tools. All thoroughly enjoyable. With this under my belt, I'll probably take a break from retro-fuse to concentrate on other things. If anyone has any problems (or successes!) using it, please drop me a line. --Jay

3 years, 5 months

1
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Doug McIlroy and Brian Kernighan talk

by arnold＠skeeve.com

Found this yesterday: https://www.youtube.com/watch?v=Xe5ffO6Ouwg Not quite an hour long. Arnold

3 years, 5 months

2
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Fwd: A bit of BTL Explorer Post Ephemera

by aaron cohen

Wow. Brings back memories On Mon, Jan 24, 2022 at 1:32 PM Robert Diamond <rob(a)robdiamond.com> wrote: > Just found this program from 1979 of an Explorer Club (aka “The Scouts”) > Family Night, which included a talk from Ken Thompson on Computer Chess. > There’s a few notable names in there. > > See PDF at > https://drive.google.com/file/d/15fXhkk9KlmJNrhGlFnWuH23XQ09vLG4o/view?usp=… -- Aaron Cohen 908-759-9069

3 years, 5 months

1
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A bit of BTL Explorer Post Ephemera

by Robert Diamond

Just found this program from 1979 of an Explorer Club (aka “The Scouts”) Family Night, which included a talk from Ken Thompson on Computer Chess. There’s a few notable names in there. See PDF at https://drive.google.com/file/d/15fXhkk9KlmJNrhGlFnWuH23XQ09vLG4o/view?usp=…

3 years, 5 months

1
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Re: [TUHS] roff(7)

by Douglas McIlroy

> Did roff do all of what troff and nroff did? No way. Ossanna deserves all the praise you give him. Roff extended runoff in various ways: relative numeric operators, e.g. .in +8 tabbing (left, right and centered) underlining tripartite headers and footers arabic and roman page numbering adjustable head and foot margins automatic hyphenation, thanks to Molly Wagner footnotes merge patterns for change marks, column separators, etc. various special requests: .ne, .ti, .tr, .po, .op (odd page) But roff did NOT have conditionals, traps, special characters, environments, or arbitrary motion control. Crucially (and ironically, because I was Mr. Macro), it did not have anything like macros, strings and diversions until after Joe pioneered them in nroff. So there was a gaping disparity: nroff was Turing complete, roff wasn't. Roff merely added features to runoff; nroff leapt into a different universe. ----------------------- The features listed above are in the January 1971 manual for BCPL roff, which is probably the anonymous reference cited in the November 1971 v1 manual. The v1 manual lists Osanna, Ken and Dennis as authors of the Unix implementation. I believe Ossanna is named because he added line-numbering--and maybe more--to entice the patent department to switch to roff. BCPL roff allowed all four arithmetic operators in contexts like .ls *3. Only + and - were allowed in nroff. Eventually both BCPL roff and nroff got number registers (defined by different commands); I don't recall which came first. BCPL roff also got a weak macro facility, definitely after nroff. Doug

3 years, 5 months

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struct(1) updating - progress

by Arnold Robbins

Hello All. If anyone is interested in struct, I have completed updating it for modern day systems. Thanks to Jay Logue for invaluable help in completing the work and to Bakul Shah for his interest and support. See https://github.com/arnoldrobbins/struct; I have merged the modernization work into the master branch. The README.md describes what was done in more detail. Doug McIlroy - if you want me to add anything to the README.md, please send it on and I will do so, quoting you as appropriate. Jay Logue and Bakul Shah - if you want me to add anything to the README.md, please let me know (privately). Thanks, Arnold

3 years, 5 months

2
1
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DEC Format floppy (for formatting disk prior to 4.2BSD install)

by Will Senn

Hi all, Has anybody ever seen a console floppy image anywhere on the internet labeled: /"RX11 VAX DSK LD DEV #1"/ It is referenced in BSD 4 documentation with respect to formatting disks (edited): USING DEC SOFTWARE TO FORMAT Warning: These instructions are for people with 11/780 CPU’s. You should shut down UNIX and halt the machine to do any disk formatting. Formatting an RP06. Load the console floppy labeled, "RX11 VAX DSK LD DEV #1" in the console disk drive, and type the following commands: >>>BOOT DIAGNOSTIC SUPERVISOR. ZZ-ESSAA-X5.0-119 23-JAN-1980 12:44:40.03 DS>ATTACH RH780 SBI RHO 8 5 DS>ATTACH RPO6 RHO DBA0 DS>SELECT DBAO DS>LOAD EVRAC DS>START/SEC:PACKINIT This is for drive 0 on mbaO; use 9 instead of 8 for mbal, etc.

3 years, 5 months

1
0
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Dot (graphviz) to ascii

by Richard Salz

>From Thomas Ptacek on twitter [1], quoting something on HackerNews [2]: a person wrote a dot-file renderer for ASCII diagrams [3] It seems to be a service; source not available. 1. https://twitter.com/tqbf/status/1483181795441004544?t=DoL8RopOYKBojkmMznSlA… 2. https://news.ycombinator.com/item?id=29969770 3. https://dot-to-ascii.ggerganov.com/

3 years, 5 months

2
2
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Re: [TUHS] BWK talk on early Unix Friday 14 January 2022

by Douglas McIlroy

> I've just watched an interesting presentation given last Friday via > video link to the Linux Conference in Australia: > Brian Kernighan > The early days of Unix at Bell Labs > https://www.youtube.com/watch?v=ECCr_KFl41E Here's an earlier incarnation of the talk: https://www.youtube.com/watch?v=nS-0Vrmok6Y I rather enjoyed seeing it with closed captions in Spanish and speakers turned off. Aided by the slides, I was pretty well able to read the Spanish, which otherwise would have been quite mysterious. Doug

3 years, 5 months

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BWK talk on early Unix Friday 14 January 2022

by Nelson H. F. Beebe

I've just watched an interesting presentation given last Friday via video link to the Linux Conference in Australia: Brian Kernighan The early days of Unix at Bell Labs https://www.youtube.com/watch?v=ECCr_KFl41E 48 minutes While most of the talk subjects are well known to TUHS list members, there are nice things said about various people, and about the value of TUHS. Other talks at the conference may be of interest as well: see the schedule at https://linux.conf.au/schedule/ ------------------------------------------------------------------------------- - Nelson H. F. Beebe Tel: +1 801 581 5254 - - University of Utah FAX: +1 801 581 4148 - - Department of Mathematics, 110 LCB Internet e-mail: beebe(a)math.utah.edu - - 155 S 1400 E RM 233 beebe(a)acm.org beebe(a)computer.org - - Salt Lake City, UT 84112-0090, USA URL: http://www.math.utah.edu/~beebe/ - -------------------------------------------------------------------------------

3 years, 5 months

2
1
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7th and 8th edition manuals, plus PDP11 processor handbook

by Terry Jones

Any takers for a (free) two-volume 7th Ed manual (1983), or ring-bound 8th Ed (1985), or PDP11 processor handbook (1981)? These would need to be picked up in Lindfield, Sydney, Australia. Condition is fair, but they've been in storage for 35 years so are slightly mouldy, but still perfectly usable. Images at http://jon.es/other/7th-ed.jpg and http://jon.es/other/8th-ed.jpg If you’d like them, let me know in email ASAP please. Regards, Terry Jones

3 years, 5 months

1
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Re: [TUHS] Brian Kernighan and very early *roff history

by jnc＠mercury.lcs.mit.edu

> From: Angelo Papenhoff > to my knowledge no troff version before the C rewrite in v7 Apologies if I missed something, but between this list and COFF there's so much low S/N traffic I skip a lot of it. Having said that, was there ever a troff in assembler? I'd always had the impression that the first one was in C. > The v6 distribution has deleted directory entries for troff source but > not the files themselves. I hope it is not lost. Maybe someone here has > an idea where it could be found? The MIT 'V6+' (I think it's probably basically PWB1) system had troff - i guess it 'fell off the back of a truck', like a lot of other stuff MIT had, such as 'typesetter C', the Portable C Compiler, etc. Theirs was modified to produce output for a Varian (I forget which model, maybe the docs or driver say). nroff on that system seems to have been generated from the troff sources; the assembler nroff sources aren't present. I looked at its n1.c, and compared it to the V7 one: https://minnie.tuhs.org/cgi-bin/utree.pl?file=V7/usr/src/cmd/troff/n1.c and this one appears to be slightly earlier; e.g. it starts: #include "tdef.h" #include "t.h" #include "tw.h" /* troff1.c consume options, initialization, main loop, input routines, escape function calling */ extern int stdi; and in the argument processing, it has quite a lot fewer. So that one is a "troff version before the C rewrite in .. v7", but it is in C. Is that of any interest? Noel

3 years, 5 months

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Brian Kernighan and very early *roff history

by Tom Lyon

Most of y'all are aware of Brian Kernighan's troff involvement. My understanding is that he pretty much took over nroff/troff after Joe Ossana died, and came out with ditroff. But Brian had much earlier involvement with non-UNIX *roff. When he was pursuing his PhD at Princeton, he spent a summer at MIT using CTSS and RUNOFF. When he came back to P'ton, he wrote a ROFF for the IBM 7094, later translated to the IBM 360. Many generations of students, myself included, use the IBM ROFF (batch, not interactive) as a much friendlier alternative to dumb typewriters. I don't know if 360 ROFF spread beyond Princeton, but I wouldn't be surprised. BTW, during my summer at Bell, nroff/troff was one of the few programs I could not port to the Interdata 8/32 - it was just a mess of essentially typeless code. I don't think Joe Ossana got around to it either before he died. -- - Tom

3 years, 5 months

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struct(1) revived! And a request for help

by arnold＠skeeve.com

Hello All. We recently discussed Brenda Baker's struct program, that read Fortran and generated Ratfor. Many of us remarked as to what a really cool program it was and how much we admired it, myself included. For fun (for some definition of "fun") I decided to try to bring the code into the present. I set up a GitHub repo with the V7, V8 and V10 code, and then started work in a separate branch. (https://github.com/arnoldrobbins/struct, branch "modernize".) The program has three main parts: - structure, which reads Fortran and outputs something that is almost Ratfor on standard output. - beautify, which reads the output of structure and finishes the job, primarily making conditions readable (.not. --> !, removing double negatives, etc.) - struct.sh - a simple shell script that runs the above two components. This is what the user invokes. The code was written in 1974. As such, it is rife with "type punning" between int, int *, int **, and char *. These produce a lot of warnings from a modern day C compiler. The code also uses a, er, "unique" bracing style, making it nearly illegible to my stuck-in-a-rut programming brain. Here is what I've accomplished so far: * Converted every function definition and declaration to use modern (ANSI) C style, adding a header file with function declarations that is included everywhere. * Run all the code through the indent program, formatting it as traditional K&R bracing style, with tabs. * Fixed some macros to use modern style for getting parameter values as strings into the macros. * Fixed a few small bugs here and there. * Fixed beautify to work with modern byacc/bison (%union) and to work with flex instead of lex. This latter was a challenge. In structure, only three files still generate warnings, but they all relate to integer <--> pointer assignment / use as. However, when compiled in 32 bit mode (gcc -m32), where sizeof(int) is the same as sizeof(pointer), despite the warnings, structure works!! Beautify works, whether compiled in 32 or 64 bit mode. What I've done so far has been mostly mechanical. I hereby request help from anyone who's interested in making progress on "the hard part" --- those three files that still generate warnings. I think the right way to go is to replace int's with a union that holds and int, a char* and an int*. But I have not had the quiet time to dive into the code to see if this can be done. Anyone who has some time to devote to this and is interested, please drop me a note off-list. Thanks, Arnold Robbins

3 years, 5 months

4
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Re: [TUHS] TeX and groff (was: roff(7))

by Jon Forrest

This is clearly getting off track of TUHS. I'll stop after this reply. > *From:* Blake McBride <blake1024(a)gmail.com> > *Date:* January 11, 2022 at 2:48:23 PM PST > *To:* Jon Forrest <nobozo(a)gmail.com> > *Cc:* TUHS main list <tuhs(a)minnie.tuhs.org> > *Subject:* *[TUHS] TeX and groff (was: roff(7))* > Although I'm not connected with the TeX community, I don't agree with > much of what you said. > > 1. TeX source to C is fine - stable and works. It would be > impossible to rewrite TeX in any other language without introducing > bugs and incompatibilities. Leaving TeX as-is means that it can be > converted to other languages too if/when C goes out of style. TeX > as-is is exactly what it is. Anything else wouldn't be TeX. I agree that Web->C works but it's a major obstacle in doing any development work on TeX. Try making a major change in the Web source that requires debugging. Anything that can pass the TeX Trip Test can be called TeX. I know of a full C reimplementation that passes the test but the author doesn't want to make it free software. There are other rewrites out there that could be candidates but someone will enough power will have to proclaim one as the official TeX alternative. > 2. Drop DVI? Are you kidding me? Although PDF may be popular now, > that may not be the case 20 years from now. A device-independent > format is what is needed, and that's what DVI is. TeX is guaranteed > to produce the exact same output 100 years from now. And .PDF isn't? .DVI was great until .PDF matured. .DVI has almost no penetration these days, whereas .PDF is everywhere. I'm not saying that .PDF will always be the proper alternative but a properly rewritten TeX should make it much easier to replace .PDF will whatever comes next. > 3. I am curious about memory limitations within TeX. TeX has various fixed sized memory pools, and contains clever code to work around limited memory. Some of the newer TeXs, like LuaTeX, use dynamic allocation but this isn't official. Given how primitive things were when TeX was developed it's a miracle it works as well as it does. > 4. Knuth is getting up in age. Someone will have to take over. Exactly. I don't follow the TeX community so I don't know what they're doing about this. Jon Forrest

3 years, 5 months

6
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Coastal cultures, collaboration, creativity and Sun vs DEC.

by Dan Cross

I've been meaning to ask about this for a while.... "... The reason why is because there was tremendous antagonism between New York and L.A. L.A. was, you know, full of color, full of acid, full of hippies, and we were not like that. We dressed in black and white. We did not like free love. ..... We took amphetamine; they took LSD. They were, you know, sort of loving and happy, and we were - we weren't really evil, we were more intellectual, more about art." [Mary Woronov, in an interview with NPR's Terry Gross on "Fresh Air", talking about New York City, Warhol's Factory and shows in Los Angeles while touring with the Velvet Underground: http://www.npr.org/templates/transcript/transcript.php?storyId=241437872] Note: I am not suggesting that anyone involved with Unix ever took amphetamines, nor, despite the usual crack about LSD and BSD, that anyone on the west coast was taking acid, though Markov's "What the Dormouse Said" would indicate that many of you WERE tripping. It seems like Unix is largely a child of the coasts. Notable work in Utah, Colorado and Chicago aside, it seems the bulk of early Unix work happened in either the greater New York metro area in northern New Jersey or the greater Bay area around San Francisco. Notable work was also done in Massachusetts, but again, that's a coastal state and I think it's fair to say that most of that was inside the route 128 corridor. Of course work was done internationally, but I'm particularly curious about differences in US culture here, and how they influenced things. The question is, to what extent did differences in coastal cultures influence things like design aesthetics? I think it's is accurate to characterize early BTL Unix by it's minimalism, and others have echoed this (cf. Richard Gabriel in the "Worse is Better" papers). But similarly, BSD has always felt like a larger system -- didn't Lions go as far as to quip about the succinctness of 6th Edition being "fixed" by 4BSD? Anyway, I believe it is fair to say that early Unix has a rather distinct feel from later BSD-derived systems and the two did evolve in different geographic locations. Furthermore, the world was not as connected then as it is now. So to what extent, if any, was this a function of the larger cultural forces at play near where that work was taking place? - Dan C.

3 years, 5 months

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Re: [TUHS] TeX and groff (was: roff(7))

by Douglas McIlroy

> If I can be so bold as to offer an interpretation: Doug's approximations > treat ellipses as mathematical objects and algorithmically determine what > pixels are closest to points on the infinitesimally-thin curves, while > Knuth's (or one his students') method acknowledges that the curve has a > width defined by the nib Just so. > I find it impossible that neither Knuth nor Hobby were unaware of McIlroy's > work and vice-versa; of course he would have known about and examined troff > just as the Bell Labs folks knew about TeX. We were generally aware of each other's work. My papers on drawing lines, circles, and ellipses on rasters, though, were barely connected to troff. Troff did not contain any drawing algorithms. That work was relegated to the rendering programs that interpreted ditroff output. Thus publication-quality rendering with support for thick lines was outsourced to Adobe and Mergenthaler. Various PostScript or ditroff postprocessors for screen-based terminals were written in house. These programs paid little or no attention to fonts and line widths. But the blit renderers made a tenuous connection between my ellipse algorithm and troff, since my work on the topic was stimulated by Rob's need for an ellipse generator. Doug

3 years, 5 months

1
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Re: [TUHS] moving directories in svr2

by jnc＠mercury.lcs.mit.edu

> From: Bakul Shah > My guess is *not* storing a path instead of a ptr to the inode was done > to save on memory. More probably speed; those old disks were not fast, and on a PDP-11, disk caches were so small that converting the path to the current directory to its in memory inode could take a bunch of disk reads. > Every inode has a linkcount so detecting when the last conn. is severed > not a problem. Depends; if a directory _has_ to be empty before it can be deleted, maybe; but if not, no. (Consider if /a/b/c/d exists, and /a/b is removed; the tree underneath it has to be walked and the components deleted. That could take a while...) In the general case (e.g. without the restriction to a tree), it's basically the same problem as garbage collection in LISP. Noel

3 years, 5 months

20
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Re: [TUHS] *roff history as told to GNU

by jnc＠mercury.lcs.mit.edu

> From: Dan Cross > a port of the _CTSS_ BCPL ROFF sources purportedly written by Doug. I > wonder if that was actually a thing, or an error? > ... > Fortunately, the source [of the original CTSS runoff] is online: > ... > Indeed; one finds the following in at least one of the Multics RUNOFF > source files: It sounds like all the steps in the chain have pretty definitive evidence - _except_ whether there was ever a CTSS RUNOFF in BCPL, from Doug. Happily, we have someone here who should be able to answer that! :-) Noel

3 years, 5 months

1
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Re: [TUHS] TeX and groff (was: roff(7))

by Jon Steinhart

Been reading the heirloom docs. Remember one thing that I disliked about troff which maybe Doug can explain. It's the language in the docs. I never understood "interpolating a register" to have any relation to the definition of interpolate that I learned in math. Made it a bit hard to learn initially. Any memory of why that term was used?

3 years, 5 months

4
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Coastal cultures, collaboration, creativity and Sun vs DEC

by Douglas McIlroy

> most, if not all of these things were after I arrived. That may indicate the youth of the narrator more than a lightening of the culture. Some practical jokes and counter-culture customs from an earlier day: When I joined the Labs, everyone talked about the escapades of Claude Shannon and Dave Hagelbarger--unicycle, outguessing machines, the finger-on-the-switch box, etc. When John Kelly became a department head he refused to have his office carpeted. That would have kept him from stubbing out cigarettes on the floor. Bill Baker may have worn a coat and tie, but he kept a jalopy in his VP parking space. Another employee had a rusty vehicle with weeds growing out of the fenders. As early as 1960 BESYS began appending fortune cookies to every printout. The counter where printouts were delivered got messed up by people pawing around to see others' fortunes. One day the audio monitor on the low bit of the 7090 accumulator stopped producing white noise (with an occasional screech for an infinite loop) and intoned in aTexas drawl, "Help, I'm caught in a loop. Help. I'm caught in a loop. Help ..." A pixelated nude mural appeared in Ed David's office. (Maybe this no longer counts as a prank. It is now regarded as a foundational event in computer art.) Ed Gilbert had a four-drawer filing cabinet labeled integers, rationals, reals, and balloon. The latter held the tattered remains of lunchtime hot-air experiments. He also had a chalkboard globe with a world map on it. It sometimes took several spins before a visitor realized that you really shouldn't be able to see all the continents at once--the map appeared twice around the circumference of the globe. CS had a Gilbert-and-Sullivan duo, Mike Lesk and Peter Neumann, who produced original entertainment for department parties. Doug

3 years, 5 months

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(no subject)

by Douglas McIlroy

> Ken and Dennis were teaching [the Votrax] to swear "Speak" being a phonetics-based program, I suspect they were exploring multiple spellings. Out of context, lots of spellings were indistinguishable. For example, cheap, cheat, cheek, chief was hard to tell from cheep, cheep, cheep, cheep.. At the risk of repeating myself, the fuck, fuck, fuck, fuck example came to the fore when a "speak" kiosk was installed at Epcot. PR folks were worried that people would try it on bad words in this public setting and asked me to block them. I said I'd block whatever words they told me to. Duly, I was sent a list--on the letterhead of an AT&T vice president. (Was that dictated to a secretary?) Later I heard that girls would often try friends' names, while boys would try bad words and exclaim that the machine didn't know them. In fact, those were among the few words the machine *did* know. Fortunately nobody ever complained that I hadn't blocked misspellings. Doug

3 years, 5 months

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Re: [TUHS] Demise of TeX and groff (was: roff(7))

by Douglas McIlroy

> Later Brian's work was updated after V7 and included some new tools, and became known as Writer's Workbench, which eventually was entered in the 'toolchest.' WWB wouldn't exist if text had not routinely existed in machine-readable form, thanks to word-processing. But the impetus for WWB came from "style", not from troff. Style was a spinoff of Lorinda Cherry's "parts", which assigned parts of speech to the words of a document. Style provided a statistical profile of the text: measures such as average word length: frequency of passives, adjectives and compound sentences, reading level, etc. WWB in turn offered writing advice based on such profiles. Style was stimulated by Bill Vesterman, a professor of English at Rutgers, who brought the idea to me. I introduced him to Lorinda, who had it running in a couple of weeks. Then Nina McDonald at USG conceived and packaged WWB as a distinct product, not just a collection of entries in man 1. Wikipedia reports a surmise that WWB sank out of sight because it was not a standard part of Unix distributions. Doug

3 years, 5 months

1
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Re: [TUHS] TeX and groff (was: roff(7))

by Jon Steinhart

Steffen Nurpmeso writes: > Note that heirloom doctools (on github) is a SysV-derived *roff Wow, thanks for mentioning this. I was unaware of it. When I recently wrote that it would be nice to add TeX's 2D formatting to troff I didn't realize that it had already been done. Something new to play with. Jon

3 years, 5 months

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Re: [TUHS] TeX and groff (was: roff(7))

by Nelson H. F. Beebe

On the subject of documtation of [nt]roff, no one seems to have mentioned Narain Gehani's two editions of ``Document Formatting and Typesetting on the UNIX System'' (700+ pages), and a second two-author volume that covers grap, mv, ms, and troff. There is a table of contents of the second edition recorded here: http://www.math.utah.edu/pub/tex/bib/typeset.html#Gehani:1987:DFT There is an entry in that file for the first edition too http://www.math.utah.edu/pub/tex/bib/typeset.html#Gehani:1986:DF The second volume, co-authored with Steven Lally, is covered here: http://www.math.utah.edu/pub/tex/bib/typeset.html#Gehani:1988:DFT ------------------------------------------------------------------------------- - Nelson H. F. Beebe Tel: +1 801 581 5254 - - University of Utah FAX: +1 801 581 4148 - - Department of Mathematics, 110 LCB Internet e-mail: beebe(a)math.utah.edu - - 155 S 1400 E RM 233 beebe(a)acm.org beebe(a)computer.org - - Salt Lake City, UT 84112-0090, USA URL: http://www.math.utah.edu/~beebe/ - -------------------------------------------------------------------------------

3 years, 5 months

1
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v7 tape in bitsavers vs recreated tape from Keith Bostic's v7 in TUHS

by Will Senn

Today I was looking around for more v7 stuff of interest that I might find on the web and came across a tape image in the ATT bits directory: http://www.bitsavers.org/bits/ATT/ labeled X7252.2015_UNIX_V7.tap and an image of the reel with original and added markings. I downloaded it and sure enough, it's a bootable v7. I then compared it with my recreated tape image from the files in the Keith Bostic folder on tuhs. The 11.7MB tapes are nearly identical, with only a handful of bytes that differ at the very end of the tape: ATT tape: 54532000 000000 000000 024000 000000 000000 000000 000077 000000 54532020 052135 014020 010000 034113 056720 023524 072143 122062 54532040 141401 000000 000000 000000 000000 000000 000000 000000 54532060 000000 000000 000000 000000 000000 000000 000000 000000 54532100 000000 000000 000000 000000 000000 000000 000000 037400 54532120 000000 000000 54532123 Bostic recreated tape: 54532000 000000 000000 024000 000000 000000 000000 177777 177777 54532020 I'm wondering - 1) Does anyone know the provenance of the X7252.2015_UNIX_V7.tap 2) Do the bytes at the end of the tapes look familiar or particularly meaningful? My knowledge of 40+ y.o. tape formats is woefully lacking, but I'm curious. Will

3 years, 5 months

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Re: [TUHS] TeX and groff (was: roff(7))

by Bakul Shah

On Jan 10, 2022, at 12:33 PM, Larry McVoy <lm(a)mcvoy.com> wrote: > TeX looks better but you instantly know it is > TeX, it has a particular look. Perhaps you’re thinking of documents using Computer Modern fonts, typeset using LaTeX’s document classes. Check out the examples here: https://tex.stackexchange.com/questions/1319/showcase-of-beautiful-typograp…

3 years, 5 months

1
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awkcc available again!

by Arnold Robbins

Hello All. I am pleased to announce that, after a multi-year effort, Chris Ramming's awkcc is now once again available for download, and this time with a more permissive license. I would like to thank Brian Kernighan, Chris Ramming and Doug McIlroy for contributing letters of support to my efforts to get this program re-released. The lion's share of the thanks must go to Martin Carroll of Nokia Bell Labs, who fought the uphill battle within Bell Labs to get permission to release the code, and who uploaded it to GitHub. Me? I pushed here and there, and contributed the actual code snapshots; it seems that Bell Labs had misplaced the code in the meantime. :-) The code, both the 1988 and 2011 versions, may be found at https://github.com/nokia/awkcc. The code is primarily of historical interest; I think it would take a significant effort to build it on a more modern system, although I think it could be done. It'd also be an effort to bring it up to date with the current Unix version of awk. Again most likely doable, but not necessarily trivial. In any case, enjoy! Arnold

3 years, 5 months

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Photos of University Computer Labs

by Alexander Jacocks

Hello, I’m looking for photographs of university computer labs from 1985 until 1995, particularly labs full of unix workstations, of course. Does anyone here have photos like that in their collection? I’m also thinking of reaching out to university archivists, but I don’t have any direct connections to any. Thanks much! - Alex

3 years, 5 months

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Bolsky's C Programmer's Handbook

by Tony Finch

I have a copy of a spiral-bound booklet with yellow covers called "The C Programmer's Reference" by Morris I. Bolsky of the Systems Training Center, AT&T Bell Laboratories, (C) 1985. A curious little snapshot of 1980s pre-ANSI C. I posted a picture of the front cover (with table of contents) at https://twitter.com/fanf/status/1475407500946157570 I think I rescued it from the office clear-out in 2013 when Cambridge University Computing Service moved out of the old city-centre offices. I probably picked it up from a stack of old books that were to be chucked; wherever I found it, I can't remember who it belonged to. And now I no longer work for the University, it has come home with me. Tony. -- f.anthony.n.finch <dot(a)dotat.at> https://dotat.at/ Southwest Forties, Cromarty, Forth, Tyne, Dogger: Southerly or southeasterly, backing easterly or northeasterly later, 4 to 6, becoming variable 3 for a time in Cromarty and Forth. Moderate, occasionally rough at first in southwest Forties, Cromarty and Dogger. Rain or showers, fog patches developing. Moderate or good, occasionally very poor.

3 years, 5 months

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asm helper routines in v7

by Douglas McIlroy

> It would be nice to hear about the rationale from a primary source. Assembly language was deemed a last resort, especially as portability was coming to the fore. As I wrote in A Research Unix Reader, "Assembly language and magic constants gradually declined from the status of the 'real truth' (v4) to utterly forgotten (v8)." In v7, assembler usage was demoted to the bottom of syscall man pages. It could also be found in /usr/src/libc/sys/*.s Doug

3 years, 6 months

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vi on v7

by Will Senn

Well, hallelujah, after much travail (I've tried this every Christmas for at least 5 years now), I have succeeded in building vi on v7 from 2bsd. Had to patch the c compiler to enlarge the symbol table, tweak some stuff here and there, but it finally built and installed without any errors, yay. Now, I just want it to do some editing, preferably in visual mode. I can call it as ex or vi: # ex : or # vi : and q will exit, yay, again! I have at least two problems: 1. It's not going "full" screen, even with TERM=vt100 or TERM=ansi set (not that I was surprised, but it'd be nice)... 2. If I type a for append and type something, there's no way to get back to the : prompt (ESC doesn't seem to work). 3. I'd like manpages (figure they might help with the above), but they're on the tape as .u files? I'm hoping this triggers some, oh yeah I remember that, type responses. Thanks, Will

3 years, 6 months

7
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asm helper routines in v7

by Will Senn

So, in v6, it was possible to use the mesg function from the system library with: ed hello.s / hello world using external mesg routine .globl mesg mov sp,r5 jsr r5,mesg; <Hello, World!\n\0>; .even sys exit as hello.sld -s a.out -l a.out Hello, World! This was because v6 included mesg in the library, in v7, it doesn't look like mesg is included, so doing the same thing as above requires that code to write the message out be included and in addition system call names are not predefined, so exit and write have to be looked up in /usr/include/sys.s, resulting in the v7 equivalent file: ed hello2.s / hello world using internal mesg routine mov sp,r5 jsr r5,mesg; <Hello, World!\n\0>; .even sys 1 mesg: mov r0,-(sp) mov r5,r0 mov r5,0f 1: tstb (r5)+ bne 1b sub r5,r0 com r0 mov r0,0f+2 mov $1,r0 sys 0; 9f .data 9: sys 4; 0:..; .. .text inc r5 bic $1,r5 mov (sp)+,r0 rts r5 as hello2.s a.out Hello, World! My questions are: 1. Is mesg or an equivalent available in v7? 2. If not, what was the v7 way of putting strings out? 3. Why aren't the system call names defined? 4. What was the v7 way of naming system calls? Will

3 years, 6 months

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New Version of Installing and Using Research Unix Version 7 in the SimH PDP-11/45 and 11/70 Emulators Available

by Will Senn

All, I've completed a new version of my "Installing and Using Research Unix Version 7 in the SimH PDP-11/45 and 11/70 Emulators" tutorial/document (wow, that's a mouthful). I'm calling it Version 2.0 - It is a completely reorganized, updated, and edited version of the document. The blog post announcement is on the blog: https://decuser.blogspot.com/ and the pdf is on google drive: https://drive.google.com/file/d/1gDBxULlpLwezH-1RO_3ou_W7trElgSgT/view?usp=… The new doc covers building a working v7 instance from tape files that will run on the SimH emulator. First, the reader is led through the restoration of a pristine v7 instance from tape to disk. Next, the reader is led through adding a regular user, making the system multi-user. Then, the reader is shown how to make the system multi-session cable allowing multiple simultaneous sessions. Finally, the system is put to use with hello world, DMR style, and the learn system is enabled. It also includes a hyperlinked table of contents. My hope is that the new version will be more useful than the prior version, as well as more accurate. I really appreciate the input and feedback y'all have given me over the intervening years. Regards, Will

3 years, 6 months

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Re: [TUHS] roff(7) [ and other related stuff ]

by jnc＠mercury.lcs.mit.edu

> From: John Cowan > Why use C syntax? What was wrong with Fortran, Lisp, or Cobol syntax, > extended to do what you wanted? Why do all hammers look basically the same? Because there's an 'ideal hammer', and over time hammer design has asymtoted toward that 'ideal hammer' design. One can't just keep improving the design indefinitely - diminishing returns set in. So I suspect there is, to some degree, a Platonic 'ideal syntax' for a 'classic block-structured' programming language, and to me, C came pretty close to it. I except LISP from that assessment, because LISP is built around a fundamentally different model of how computations/algorithms are organized, and C and LISP aren't directly comparable. But that realization points to a deeper bug with the 'Platonic ideal language' concept above, which is that languages are fundamentally, albeit at a very deep conceptual level, tied to the basic concept of the computing hardware they are to run on. C/COBOL/FORTRAN/etc are all for von Neumann-like (in a broad sense) computing engines - a single thread of computation, which happens sequentially. But we've pushed that paradigm about as far as it can go, we're into diminishing returns territory on that one. The future, starting with the hardware, will be very different - and will need quite different languages. (Go, from what little I know of it, is a baby step in this direction - it is intended to make it easy to use multiple simultaneous loci of execution, making use of the mutiple cores that are common now.) I suspect we'll be shifting to radically different paradigms, 50 years from now - massively parallel computing meshes (think Connection Machines on steroids - or the human brain), and those will use fundamentally different computing paradigms, and programming languages for them, which in turn will need very different syntax. Noel

3 years, 6 months

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Re: [TUHS] roff(7) [ and other related stuff ]

by Douglas McIlroy

> Lisp, _that's_ elegant. The machine shines through Lisp even more brightly than it does through C. Lisp attains incredible power from a tiny base: car, cdr, cons, cond, T, F, null, lambda, def, exuding elegance that survives even in a raging sea of parentheses. For Lisp-friendly applications nowadays, I prefer Haskell, which is much further away from the machine. Haskell code approaches--and sometimes surpasses--the cleanliness of good mathematical notation. For string processing, I remember Snobol 3 with great fondness. But for everyday work with arrays and numbers, C is the workhorse. Still, I wish that C would evaluate comma expressions in parallel rather than in series, as in (a,b) = (b,a). Doug

3 years, 6 months

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v7 /etc/ttys and /usr/adm/wtmp shenanigans

by Will Senn

I enabled user accounting on my v7 instance and I noticed it "growing without bound" and while this is noted as a possibility in the ac(1) man page, I was pretty sure the original authors didn't mean 30k a second. I scratched my head and thought for a while and then started experimenting to see what the heck was going on. I removed /usr/adm/wtmp (which I had created to enable accounting in the first place) and the little red disk write arrow on my mac went away, but not the little green disk read arrow... hmm. Something was keeping my v7 instance very busy reading disk, that was for sure. I went through a few (dozens) more tests and experiments, reread a bunch of man pages, Ritchie's v7 install note, and thought some more and here's what I came up with... If you modify your system to add dci lines and you enable some ttys in /etc/ttys and you enable user accounting. Then, the next time you boot into a kernel that doesn't have dci support, init or some other process will try and fail to read the enabled ttys, log something in /usr/adm/wtmp, if it exists, and then loop (very quickly), over and over and over. If you aren't paying attention, this will hardly be noticeable on modern hardware running simh, but I'm guessing this would have been disastrous, back in the day. The simple solution is to boot w/dci enabled when you have ttys enabled, and only boot w/o dci enabled when you have disabled the ttys. I'm guessing that this wasn't really ever an issue, back in the day, as folks prolly didn't just yank their dci's and reboot a different kernel? But, such are the joys of simulation. Anyhow, if this doesn't sound like a very likely or reasonable analysis of what was happening, I'd appreciate your letting me know, or if you've experienced something like it before, it'd be great to know that I'm not alone in this silliness. Will

3 years, 6 months

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learn command in v7

by Will Senn

I'm pretty sure that I asked about learn ages back, but I couldn't find any reference to it in the archives. So, I thought I would close the possibly imaginary loop on it. Cuz, I figured it out, and it may prove useful to others or with my track record, even myself in the future :). Learn works fine in v7. It just needs to be properly installed. The command is there already, so you may not need to follow all of the steps below, but it doesn't hurt: I did this as root, but it could possibly be done as another user, I'm not sure. cd /usr/src/cmd/learn make make lessons make play; make log That's it. make will complain about missing files that it tries to delete, but these can be safely ignored, since make then creates them anyway. Here's the result run as a normal user: $ learn These are the available courses - files editor morefiles macros eqn C If you want more information about the courses, or if you have never used 'learn' before, type 'return'; otherwise type the name of the course you want, followed by 'return'. macros If you were in the middle of this subject and want to start where you left off, type the last lesson number the computer printed. To start at the beginning, just hit return. This script deals with the use of the "-ms" macro package to produce Bell Laboratories style documents. Before trying it, you should be familiar with the editor. To test that, please enter the file typed below, exactly as is, into file "decl". Then type "ready". .PP When in the course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth the separate and equal station to which the laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation. $ ed decl ?decl a .PP When in the course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth the separate and equal station to which the laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation. . w 410 q $ ready Good. Lesson 1.1a (1) When you have some document typed in "-ms" style, you run it off on your terminal by saying: nroff -ms file where "file" is the name of the file it is on. For example, the file "decl" in this directory is in a suitable format for running off this way. Do so. Then type "ready". $ Interrupt. Want to go on? n Bye. $ Pretty slick, really, once you realize that the $ prompt isn't really your shell, it's a shell within learn. Also, there's no learn manpage although there is a document in vol2 of the programmer's manual that describes the program. I couldn't figure out the canonical way to exit, so I just CTRL-DELETE on my mac, which I figure it CTRL-BREAK (^C?). That seems to work. Oh, and according to /usr/src/cmd/learn/README, if you have any trouble: Please report problems, bad lessons, etc., to Brian Kernighan, MH 6021, 2C-518, or Mike Lesk, MH 6377, 2C-572. Thanks. Enjoy, and happy New Year, folks! Will

3 years, 6 months

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Re: [TUHS] v7 software

by Douglas McIlroy

> Joy’s original 2BSD tape will give you UCB Pascal. While I agree with Kernighan that Pascal is not my favorite programming language, UCB Pascal is my favorite compiler because of its spectacularly good syntax diagnostics. The diagnostics are automatically generated, so they have a completely consistent style and never go down rabbit holes trying to explain an error. The UCB trick is to report the exact spot where LR parsing chokes and suggest a canonical alternate token that allows progress. This simple strategy is startlingly effective; the compiler taught me Pascal in an evening. It occurred to me that Pascal would be a suitable language in which to express a certain algorithm. Having skimmed the Pascal report a year or more earlier, I knew it was a pretty typical language, so I grabbed a sample program from somewhere and plowed ahead. I made mistake after mistake, but every diagnostic was instantly suggestive. By the end of the session I had a polished working program. In due time it was accepted for publication. Doug

3 years, 6 months

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v7 software

by Will Senn

I'm tooling around doing my annual dive into operating systems ancient and not-so-ancient and I've gotten back around to v7 because it has a working f77 in baseline. The 3b2 has f77 as an installable package but it crashes and burns with read statements like: read *,var - in both sysvr2 and sysvr3. After consulting with the fortran expert, I'm gonna chalk it up to "man there's a lot of backstory to these seemingly simple issues" and just work with v7... in full disclosure f77 also seems to work fine on 211bsd, but that's too new for today's dive :). Anyhow, I ran through my install notes from back in 2017 and did a few updates on them to update urls (would everyone just go ahead and move to https already?), fix some clunky examples, fix some typos, and update to a more recent host environment (although some would argue that Mojave is out of date - just give me a drop in replacement for Adobe Acrobat Pro X (a 32 bit app) that doesn't phone home every 5 minutes and I'll move to Monterey). Version 1.7 of the doc is posted on the blog: https://decuser.blogspot.com/ Anyway, now I'm ready to add stuff to my shiny new v7 instance and document the additions. So, on to the question of the hour... I did some looking around and couldn't easily locate any v7 software archives for additional software that will run on v7 (not the distros, which are adequately hosted in the Unix Archive). Stuff like pascal, fortran iv, fortran 90, basic, lisp and the ilk. Do y'all know of any good caches? Later, Will

3 years, 6 months

2
1
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v7 bas - "Ken Thompson's BASIC"

by Will Senn

So, I was bemoaning the fact that I couldn't really make sense of the bas command in v7. In sysv2, it works and is similar enough to modern dialects that I was able to get a simple example working, but with v7, the best I was able to do was use it interactively, as a calculator. Then I went looking for v7 videos on youtube and came across this Dr. Dave's Diversions video: https://www.youtube.com/watch?v=LZUMNZTUJos In it Dr. Dave demos a few simple versions of 99 bottles of beer in v7. Wow! I wondered how he'd glommed the inner workings of bas - did he read a book, just know it naturally, phone a friend, or what? Well, as it turned out, he... wait for it... read the bas(1) man page! Wha?! Ridiculous. So, I pulled out my v7 phone book and read the bas(1) man page and sure enough, it was all there... how '_' is used for negation, how those arcane for loops work, arrays?!, function calls?!, etc and so on, all in 3 short pages. So, two observations: 1. Those man pages from back in the day - wow. So terse, yet so well written. With a little help from a friend (thanks, Dr Dave), they're really all you need, sometimes. 2. Those early apps - wow. So obscure these days, but so ahead of their time, too (thanks, Ken for making Dec 2021 interesting by doing what you did back in the early 70's). And a question (you knew it was coming): Besides the bas(1) page, is there anything else written on Ken's basic out there in the wild? Oh, and a bonus question, draw and erase from v5 appear to still be around in v7, but not documented in the man page. Did it work and has anyone written a Tektronix 611 emulator that works with v7? Thanks, Will

3 years, 6 months

2
1
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moving directories in svr2

by Will Senn

I'm a little flummoxed in trying to move some directories around in svr2. Shouldn't the following work? mkdir a mkdir b mv a b I get the following error: mv: b exists I tried many of the possible variants including: mv a b/ mv: b/ exists mv a b/a mv: directory rename only cd b mv ../a . mv: . exists mv ../a ./ mv: ./ exists mv ../a ./a mv: directory rename only If moving directories into existing directories wasn't allowed in those days, 1) how were directories managed? and 2) when did moving directories into directories become a thing?

3 years, 6 months

8
14
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BSD 2.11 documentation

by Will Senn

Are there any extant 2.11 manuals other than the online manual and various install and configure PDFs, available for download? Also, am I understanding correctly that 2.11 is 2.10 plus some 4.3 backports and a ton of patches? If there aren’t any 2.11 specific docs, what would be the closest of what is available? Will Sent from my iPhone

3 years, 6 months

2
1
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Re: [TUHS] moving directories in svr2

by jnc＠mercury.lcs.mit.edu

> From: Clem Cole > Try it on V6 or V7 and you will get 'directory exists' as an error. The V6 'mv' is prepared to move a directory _within_ a directory (i.e. 'rename' functionality). I'm not sure why it's not prepared to move within a partition; probably whoever wrote it wasn't prepared to deal with all the extra work for that (unlink from the old '..', then link to the '..' in the new directory, etc, etc). (The MIT PWB1 had a 'mvdir' written by Jeff Schiller, so PWB1 didn't have 'move directory' functionality before that. MIT must have been using the PWB1 system for 6.031, which I didn't recall; the comments in 'mvdir' refer to it being used there.) The V6 'mv' is fairly complicated (as I found out when I tried to modify it to use 'smdate()', so that moving a file didn't change its 'last write' date). Oddly enough, it is prepared to do cross-partition 'moves' (it forks a 'cp' to do the move). Although on V6, 'cp' only does one file; 'cp *.c {dest}' was not supported, there was 'cpall' for that. (Why no 'mvall', I wonder? It would have been trivial to clone 'cpall'.) Run fact; the V6 'mv' is the place that has the famous (?) "values of B will give rise to dom!" error message (in the directory-moing section). > if the BSD mv command for 4.1 supported it. If it did then it was not > atomic -- it would have had to create the new directory, move the > contents independently and then remove the old one. Speaking of atomic operation, in V6 'mkdir' (not being a system call) was not atomic, so if interrupted at 'just the right time', it could leave the FS in an inconsistent state. That's the best reason I've come across to make 'mkdir' a system call - it can be made atomic that way. Noel

3 years, 6 months

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Re: [TUHS] moving directories in svr2

by Douglas McIlroy

> what was the last Unix version > that let users make arbitrary links, such that the file system was no > longer a DAG? I recall in v6 days hearing that earlier Unix allowed > this, and that cleanup (via icheck and friends) got to be near > impossible. >From v1 on (I'm not sure about PDP-7 Unix) only the superuser could do that, so what you heard strikes me as urban legend. Perhaps some installations abused root privilege to scramble the file system, but I certainly didn't see that happen in Research systems. Doug

3 years, 6 months

5
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Re: [TUHS] moving directories in svr2

by Bakul Shah

On Dec 29, 2021, at 8:01 AM, Bakul Shah <bakul(a)iitbombay.org> wrote: > On Dec 29, 2021, at 7:18 AM, Clem Cole <clemc(a)ccc.com> wrote: >> >> Think about the UNIX FS and the link system call. How is mv implemented? You link the file to the new directory and the unlink it from the old one. But a directory file can not be in two directories at the same time as the .. link would fail. > > Don’t see why linking a dir in two places is a problem. To expand on this a bit, the “cd ..” case can be handled by not storing a .. link in a dir. in the first place! Store the $PWD path in the u struct. Then cd .. would simply lop off the last component, if one exists. Thus .. takes you back only on the path you used! This also takes care of the issue with symlinks (& does what csh did in user code).

3 years, 6 months

6
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Re: [TUHS] moving directories in svr2

by Douglas McIlroy

The first specific mention of moving directories in Research is in v10, but I'm sure that was implemented considerably earlier. The only things special about moving a directory were that it needed root privilege and checked against moving a directory into itself. As with ordinary files, copying (with loss of hard links) happened only when moving between different file systems. As far as I know, no atomicity precautions were taken.

3 years, 6 months

1
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manpages in svr2

by Will Senn

The core system of svr2 distributed by ATT for the 3b2-400 doesn't come with manpages installed. Does anybody know of a set of manpages for SVR2 that can be installed into the system? It's not the end of the world, if not... the user guide is available as a pdf, but it'd be handy to have man on the system. Will

3 years, 6 months

4
5
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echo in v6/v7/sysvr2

by Will Senn

Is it possible to use echo to send a vt-100 escape sequence in v6/v7/sysvr2? I can write a c program to clear the screen and go home in sysvr2: #define ASCII_ESC 27 main() { printf( "%c[2J", ASCII_ESC ); printf( "%c[H", ASCII_ESC ); } and it works fine. I can type the escape sequences in as well, but I'd just as soon write a shell script with an echo '[[2J;[[H' or something similar without having to compile a clear command. Is it possible and what do I need to know :)?. Thanks, Will

3 years, 6 months

2
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Re: [TUHS] svr2 delete behavior

by jnc＠mercury.lcs.mit.edu

> From: Will Senn > anything similar to modern behavior when handling the delete/backspace > key where the character is deleted from the input and rubbed out? The > default, like in v6/v7 for erase and kill is # and @. I can live with > this, if I can't get it to do the rubout, because at least you can see > the # in the input I use ASCII 'backspace' (^H) on my V6, and it 'sort of' works; it doesn't erase the deleted character on the screen, but if one then types corrected characters, they overlay the deleted ones, leaving the corrected input. That should work on everything later than V6. The MIT PWB1 tty handler (link in a prior message) not only supported a 'kill line' (we generally used '^U') which actually visibly deleted the old line contents (on screen terminals, of course; on printing terminals you're stuck), it also had suppport for '^R' (re-type line) and some other stuff. Noel

3 years, 6 months

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svr2 delete behavior

by Will Senn

Did svr2 have anything similar to modern behavior when handling the delete/backspace key where the character is deleted from the input and rubbed out? The default, like in v6/v7 for erase and kill is # and @. I can live with this, if I can't get it to do the rubout, because at least you can see the # in the input, but if I can figure out how to get it to rubout the last character, I'd map erase to DEL, which I believe to be ^U (but since it's invisible, it's confusing when it doesn't rubout). Will

3 years, 6 months

2
2
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Are there images of any SVR2's available online?

by Will Senn

All, Are there any bootable media available for any SVR 2 systems available online? Or are they all under IP lock and key? If so, what's the closest system that is available to get a feel for that variety of OS? Happy holidays, folks. Will

3 years, 6 months

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ksh88 source code?

by Warren Toomey

Hi all, I received an e-mail looking for the ksh-88 source code. A quick search for it on-line doesn't reveal it. Does anybody have a copy? Cheers, Warren Original e-mail: I recently built a PiDP11 and have been enjoying going back in time to 2.11BSD.. I was at UC Davis in the the early 1980's and we had a few PDP-11/70's running 2.8/2.9 BSD. Back then we reached out to David Korn and he sent us the source for KSH -- this would have been in 1985ish if I remember, and we compiled it for 2.9 & 4.1BSD, Xenix, and some other variants that used K&R C. It may have been what was later called ksh88. I wish I still had the files from then.. I was wondering if you might know if there's an older version like this or one that's been ported for 2.11BSD? Many thanks, Joe

3 years, 6 months

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COFF subscription

by Clay Hickman

Hey Warren, First and foremost; Thank you so much for maintaining this mailing list, and for including me within the subscribers list. I find myself intrigued by some of the topics that transfer over to the “COFF” mailing list. Could you include me on that mailing list as well? Peace.

3 years, 6 months

1
0
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Re: [TUHS] ksh88 source code?

by norman＠oclsc.org

Thomas Paulsen: bash is clearly more advanced. ksh is retro computing. ==== Shell wars are, in the end, no more interesting than editor wars. I use bash on Linux systems because it's the least-poorly supported of the Bourne-family shells, besides which bash is there by default. Ksh isn't. I use ksh on OpenBSD systems because it's the least-poorly supported of the Bourne-family shells, besides which kh is there by default. Bash isn't. I don't actually care for most of the extra crap in either of those shells. I don't want my shell to do line editing or auto-completion, and I find the csh-derived history mechanisms more annoying than useful so I turn them off too. To my mind, the Research 10/e sh had it about right, including the simple way functions were exported and the whatis built-in that told you whether something was a variable or a shell function or an external executable, and printed the first two in forms easily edited on the screen and re-used. Terminal programs that don't let you easily edit input or output from the screen and re-send it, and programs that abet them by spouting gratuitous ANSI control sequences: now THAT's what I call retro-computing. Probably further discussion of any of this belongs in COFF. Norman Wilson Toronto ON

3 years, 6 months

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Re: [TUHS] ksh88 source code?

by norman＠oclsc.org

John Cowan: Unfortunately, approximately nobody except you has access to [the 10/e sh] man page. Can you post or email it? === I am happy to remind you that you're a few years out of date: https://minnie.tuhs.org/cgi-bin/utree.pl?file=V10/man/man1/sh.1 Norman Wilson Toronto ON

3 years, 6 months

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Faces of Open Source (and NFTs)

by Dan Cross

So a number of Unix luminaries were photographed as part of the "Faces of Open Source" project. I have to admit, the photos themselves are quite good: https://www.facesofopensource.com/collect/ It seems that the photographer is now selling NFTs based on those photos, which is...a thing. - Dan C.

3 years, 6 months

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Re: [TUHS] PDP 11/23 running UNIX version 6 at VCF Midwest!

by jnc＠mercury.lcs.mit.edu

> From: Paul Ruizendaal > Does anyone remember, was this a real life bug back in 6th edition The 'V6' at MIT (actually, PWB1) never had an issue, but then again, its TTY driver (here: http://ana-3.lcs.mit.edu/~jnc/tech/unix/mit/dmr/tty.c if anyone wants to see it) was heavily re-written. But from the below, it's almost certainlynothing to do with the TTY code... > From: Dave Plonka > one experiment we did was to redirection the bas(1)ic program's output > to a file and what we found was that (a) characters would still > sometimes be lost Good test. If you all want to chase this down (I can lend V6 expertise, if needed), I'd say the first step is to work out whether it's the application, or the system, losing the characters. To do that, I'd put a little bit of code in write() to store a copy of data sent through that in a circular buffer, along with tagging it with the writing process, etc. Once you figure out where it's getting lost, then you can move on to how/why. > From: Clem Cole > First Sixth Edition does not have support for either the 11/23 Yeah, but it's super-trivial to add /23 support to V6: http://gunkies.org/wiki/Running_UNIX_V6_on_an_-11/23 The only places where change is needed (no LKS register, no switch register, and support for more than 256KB of main memory - and that one one can get by without), it's hard to see how they could cause this problem. > One other thought, I'm pretty sure that Noel's V6+ system from MIT can > support a 23 No, we never ran than on a /23 BITD (no need, no mass storage); and I have yet to bring the V6+ system up (although I have all the bits, and intend to, at some point, to get its TCP/IP running). I've been using stock (well, hacked a bit, in a number of ways - e.g. 8-bit serial line output) V6. Noel

3 years, 6 months

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32V with virtual memory

by Paul Ruizendaal

I am making some slow progress on the topic of Tom Reiser’s 32V with virtual memory. Two more names popped up of folks who worked with his virtual memory code base at Bell Labs / USG in the early 80’s: Robert (Bob) Baron and Jim McCormick. Bob Barron was later working on Mach at CMU. If anybody on this list has contact suggestions for these two folks, please send a private message. Paul

3 years, 6 months

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PDP 11/23 running UNIX version 6 at VCF Midwest!

by Paul Ruizendaal

> While doing some end of year retrocomputing revisiting, I thought some > of you might enjoy this - there is hope for the next generation(s)! ;) > https://www.youtube.com/watch?v=_Zyng5Ob-e8 <https://www.youtube.com/watch?v=_Zyng5Ob-e8> Thanks for that video link! I noticed the bit at the end about V6 and the occasional dropped character and that this was not a serial line issue. I have the same issue in my V6 port to the TI-990 and always assumed that it was a bug I introduced myself when hacking the tty driver. Does anyone remember, was this a real life bug back in 6th edition back in the 1970’s? Maybe only showing at higher baud rates? Paul

3 years, 6 months

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Re: [TUHS] {TUHS} efl

by Douglas McIlroy

> there was a commercial package called Spag i which claimed to un-spagatti-ify your code which i always wanted but, could never afford. You needed struct(1) in v7. It did precisely that, converting Fortran to Ratfor. Amazingly (to me, anyway) it embodied a theorem: a Fortran program has a canonical form. People found the converted code to be easier to understand--even when they had written the original code themselves. Doug

3 years, 6 months

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efl

by Steve Simon

hi, having supported Pafec and then in a different job flow3d, i was most interested in anything that could make large fortran packages more manageable. there was a commercial package called Spag i which claimed to un-spagatti-ify your code which i always wanted but, could never afford. the best i managed was sed and awk scripts to split huge fortran files into one file per function and build a makefile. this at least made rebuilds quicker. i do not miss maintaining fortran code hacked by dozens of people over many decades. -Steve

3 years, 6 months

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PDP 11/23 running UNIX version 6 at VCF Midwest!

by Dave Plonka

Hi folks! While doing some end of year retrocomputing revisiting, I thought some of you might enjoy this - there is hope for the next generation(s)! ;) https://www.youtube.com/watch?v=_Zyng5Ob-e8 In this video I share my personal pick for "best" demo at VCF Midwest: Gavin's PDP 11/23 running UNIX Version 6! We write and run a simple BASIC program in Ken Thompson's bas(1), finding some quirks with this (currently) entirely floppy-based system, possible having to do with a glitch in disk I/O. (We discovered bas(1) uses a temporary file as backing store.) Filmed at the Vintage Computer Festival Midwest: VCF Midwest 16, September 11, 2021 http://vcfmw.org/ Here's the source code to the simple program we wrote; you can also run it on modern machines if you install a Research UNIX version using SimH (pdp-11 simulator). 5 goto 30 10 for col = 1 arg(1) 12 prompt " " 14 next 20 print "Welcome to VCF Midwest!" 25 return 30 for x = 0 55 40 10(x) 50 next 60 for x = _56 _1 70 10(_x) 80 next -- dave(a)plonka.us http://www.cs.wisc.edu/~plonka/

3 years, 6 months

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efl(1) anyone?

by arnold＠skeeve.com

Hi TUHS folks! After having reincarnated ratfor, I am wondering about Stuart Feldman's efl (extended fortran language). It was a real compiler that let you define structs, and generated more or less readable Fortran code. I have the impression that it was pretty cool, but that it just didn't catch on. So: - Did anyone here ever use it personally? - Is my impression that it didn't catch on correct? Or am I ignorant? Thoughts etc. welcome. :-) Thanks, Arnold

3 years, 6 months

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Belated Introduction

by Alexander Jacocks

Spurred on by Bryan, I thought I should properly introduce myself: I am a fairly young Unix devotee, having gotten my start with System V on a Wang word processing system (believe it or not, they made one!), at my mother’s office, in the late 1980s. My first personal system, which ran SLS Linux, came about in 1992. I am a member of the Vintage Computing Federation, and have given talks and made exhibits on Unix history at VCF’s museum, in Wall, New Jersey. I have also had the pleasure to show Brian Kernighan and Ken Thompson, who are two of my computing heroes, my exhibit on the origins of BSD Unix on the Intel 386. I learned C from Brian’s book, as probably did many others here. I have spent my entire professional career supporting Unix, in some form or another. I started with SunOS at the National Institutes of Health, in Bethesda, Maryland, and moved on to Solaris, HP-UX, SCO, and finally Linux. I worked for AT&T, in Virginia, in the early 2000s, but there were few vestiges of Unix present, other than some 3b1 and 3b2 monitors and keyboards. I current work for Red Hat, in Tyson’s Corner, Virginia, as a principal sales engineer, where I spend most of my time teaching and presenting at conferences, both in person and virtual. Thank you to everyone here who created the tools that have enabled my career and love of computing! - Alexander Jacocks

3 years, 7 months

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New Member

by Bryan St. Amour

Hello! I have just joined this mailing list recently, and figured I would give an introduction to myself. My first encounter with Unix took place in 2006 when I started my undergraduate studies in Computer Science. The main servers all ran Solaris, and we accessed them via thin clients. Eventually I wanted a similar feeling operating system for my personal computer, so that I could do my assignments without having to always log into the school servers, and so I came across Linux. I hopped around for a while, but eventually settled with Slackware for my personal computers. Nowadays I run a mixture of Linux and BSD operating systems for various purposes. Unfortunately my day job has me writing desktop software for Windows (no fun there :(), so I'm thankful to have found a group of people with similar computing interests as myself, and I look forward to chatting with you all! Regards, Bryan St. Amour

3 years, 7 months

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Re: [TUHS] [COFF] Book Recommendation

by jnc＠mercury.lcs.mit.edu

OK, this is my last _civil_ request to stop email-bombing both lists with trafic. In the future, I will say publicly _exactly_ what I think - and if screens still had phosphor, it would probably peel it off. I can see that there are cases when one might validly want to post to both lists - e.g. when starting a new discusson. However, one of the two should _always_ be BCC'd, so that simple use of reply won't generate a copy to both. I would suggest that one might say something like 'this discussion is probably best continued on the <foo> list' - which could be seeded by BCCing the _other_. Thank you. Noel

3 years, 7 months

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Re: [TUHS] Book Recommendation

by Douglas McIlroy

http://www.cs.ox.ac.uk/jeremy.gibbons/publications/fission.pdf Duncan Mak wrote > Haskell's powerful higher-level functions > make middling fragments of code very clear, but can compress large > code to opacity. Jeremy Gibbons, a high priest of functional > programming, even wrote a paper about deconstructing such wonders for > improved readability. > I went looking for this paper by Jeremy Gibbons here: https://dblp.org/pid/53/1090.html but didn't find anything resembling it. What's the name of the paper?

3 years, 7 months

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UNIX/AT&T patent licensing

by Warren Toomey

All, I got this e-mail forwarded on from John Fox via Eric S. Raymond. Cheers, Warren Hi Eric, I think you might find this interesting. I have a 2001 copy of your book. I dog-eared page 9 twenty years ago because of this section: It spread very rapidly with AT&T, in spite of the lack of any formal support program for it. By 1980 it had spread to a large number of university and research computing sites, and thousands of hackers considered it home. Regarding the "spread", I believe one of the contributing factors was AT&T's decision to give the source code away to universities. And in doing so, unwittingly provided the fertile soil for open source development. I happen to know the man who made that decision. He was my father-in-law. He died Tuesday. He had no idea what UNIX was, and had no idea what his decision helped to create. Funny when things we do have such a major impact without us even knowing. That was certainly true in this case. Anyway, I thought you'd be interested to know. His name is John (Jack) H. Bolt. He was 95. PS, before making the decision, he called Ken Olson at DEC to see if he'd be interested in buying it, lock, stock, and barrel. Jack's opening offer was $250k. Olson wasn't interested. And on that, Jack's decision was made. John Fox

3 years, 7 months

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Re: [TUHS] Book Recommendation

by Douglas McIlroy

>> The former notation C(B(A)) became A->B->C. This was PL/I's gift to C. > You seem to have a gift for notation. That's rare. Curious what you think of APL? I take credit as a go-between, not as an inventor. Ken Knowlton introduced the notation ABC in BEFLIX, a pixel-based animation language. Ken didn't need an operator because identifiers were single letters. I showed Ken's scheme to Bud Lawson, the originator of PL/I's pointer facility. Bud liked it and came up with the vivid -> notation to accommodate longer identifiers. If I had a real gift of notation I would have come up with the pipe symbol. In my original notation ls|wc was written ls>wc>. Ken Thompson invented | a couple of months later. That was so influential that recently, in a paper that had nothing to do with Unix, I saw | referred to as the "pipe character"! APL is a fascinating invention, but can be so compact as to be inscrutable. (I confess not to have practiced APL enough to become fluent.) In the same vein, Haskell's powerful higher-level functions make middling fragments of code very clear, but can compress large code to opacity. Jeremy Gibbons, a high priest of functional programming, even wrote a paper about deconstructing such wonders for improved readability. Human impatience balks at tarrying over a saying that puts so much in a small space. Yet it helps once you learn it. Try reading transcripts of medieval Arabic algebra carried out in words rather than symbols. Iverson's hardware descriptions in APL are another case where symbology pays off. Doug

3 years, 7 months

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Ratfor revived!

by Arnold Robbins

Hi All. Mainly for fun (sic), I decided to revive the Ratfor (Rational Fortran) preprocessor. Please see: https://github.com/arnoldrobbins/ratfor I started with the V6 code, then added the V7, V8 and V10 versions on top of it. Each one has its own branch so that you can look at the original code, if you wish. The man page and the paper from the V7 manual are also included. Starting with the Tenth Edition version, I set about to modernize the code and get it to compile and run on a modern-day system. (ANSI style declarations and function headers, modern include files, use of getopt, and most importantly, correct use of Yacc yyval and yylval variables.) You will need Berkely Yacc installed as byacc in order to build it. I have only touch-tested it, but so far it seems OK. 'make' runs in like 2 seconds, really quick. On my Ubuntu Linux systems, it compiles with no warnings. I hope to eventually add a test suite also, if I can steal some time. Before anyone asks, no, I don't think anybody today has any real use for it. This was simply "for fun", and because Ratfor has a soft spot in my heart. "Software Tools" was, for me, the most influential programming book that I ever read. I don't think there's a better book to convey the "zen" of Unix. Thanks, Arnold

3 years, 7 months

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Re: [TUHS] Encoding an ISA: Random Logic vs. Control Stores

by Douglas McIlroy

My take on defining random logic random logic : hardware :: spaghetti code : software Doug

3 years, 7 months

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Encoding an ISA: Random Logic vs. Control Stores

by pbirkel＠gmail.com

I believe that the PDP-11 ISA was defined at a time when DEC was still using random logic rather than a control store (which came pretty soon thereafter). Given a random logic design it's efficient to organize the ISA encoding to maximize its regularity. Probably also of some benefit to compilers in a memory-constrained environment? I'm not sure at what point in time we can say "lots of processors" had moved to a control store based implementation. Certainly the IBM System/360 was there in the mid-60's. HP was there by the late 60's. -----Original Message----- From: TUHS <tuhs-bounces(a)minnie.tuhs.org> On Behalf Of Larry McVoy Sent: Monday, November 29, 2021 10:18 PM To: Clem Cole <clemc(a)ccc.com> Cc: TUHS main list <tuhs(a)minnie.tuhs.org>; Eugene Miya <eugene(a)soe.ucsc.edu> Subject: Re: [TUHS] A New History of Modern Computing - my thoughts On Sun, Nov 28, 2021 at 05:12:44PM -0800, Larry McVoy wrote: > I remember Ken Witte (my TA for the PDP-11 class) trying to get me to > see how easy it was to read the octal. If I remember correctly (and I > probably don't, this was ~40 years ago), the instructions were divided > into fields, so instruction, operand, operand and it was all regular, > so you could see that this was some form of an add or whatever, it got > the values from these registers and put it in that register. I've looked it up and it is pretty much as Ken described. The weird thing is that there is no need to do it like the PDP-11 did it, you could use random numbers for each instruction and lots of processors did pretty much that. The PDP-11 didn't, it was very uniform to the point that Ken's ability to read octal made perfect sense. I was never that good but a little google and reading and I can see how he got there. ... --lm

3 years, 7 months

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Encoding an ISA: Random Logic vs. Control Stores

by Paul Ruizendaal

For DEC memo’s on designing the PDP-11 see bitsavers: http://www.bitsavers.org/pdf/dec/pdp11/memos/ (thank you Bitsavers! I love that archive) Ad van de Goor (author of a few of the memo’s) was my MSc thesis professor. I recall him saying in the early 80’s that in his view the PDP-11 should have been an 18-bit machine; he reasoned that even in the late 60’s it was obvious that 16-bits of address space was not enough for the lifespan of the design. --- For those who want to experiment with FPGA’s and ancient ISA’s, here is my plain Verilog code for the TI 9995 chip, which has an instruction set that is highly reminiscent of the PDP-11: https://gitlab.com/pnru/cortex/-/tree/master The actual CPU code (TMS99095.v) is less than 1000 lines of code. Paul

3 years, 7 months

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A New History of Modern Computing - my thoughts

by Jon Steinhart

Eugene Miya visited by last week and accidentally left his copy of the book here so I decided to read it before he came back to pick it up. My overall impression is that while it contained a lot of information, it wasn't presented in a manner that I found interesting. I don't know the intended target audience, but it's not me. A good part of it is that my interest is in the evolution of technology. I think that a more accurate title for the book would be "A New History of the Business of Modern Computing". The book was thorough in covering the number of each type of machine sold and how much money was made, but that's only of passing interest to me. Were it me I would have just summarized all that in a table and used the space to tell some engaging anecdotes. There were a number of things that I felt the book glossed over or missed completely. One is that I didn't think that they gave sufficient credit to the symbiosis between C and the PDP-11 instruction set and the degree to which the PDP-11 was enormously influential. Another is that I felt that the book didn't give computer graphics adequate treatment. I realize that it was primarily in the workstation market segment which was not as large as some of the other segments, but in my opinion the development of the technology was hugely important as it eventually became commodified and highly profitable. Probably due to my personal involvement I felt that the book missed some important steps along the path toward open source. In particular, it used the IPO of Red Hat as the seminal moment while not even mentioning the role of Cygnus. My opinion is that Cygnus was a huge icebreaker in the adoption of open source by the business world, and that the Red Hat IPO was just the culmination. I also didn't feel that there was any message or takeaways for readers. I didn't get any "based on all this I should go and do that" sort of feeling. If the purpose of the book was to present a dry history then it pretty much did it's job. Obviously the authors had to pick and choose what to write about and I would have made some different choices. But, not my book. Jon

3 years, 7 months

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Re: [TUHS] A New History of Modern Computing - my thoughts

by jnc＠mercury.lcs.mit.edu

> The ++ operator appears to have been. One would expect that most people on this list would have read "The Development of the C Language", by Dennis Ritchie, which makes perfectly clear (at 'More History') that the PDP-11 had nothing to do with it: Thompson went a step further by inventing the ++ and -- operators, which increment or decrement; their prefix or postfix position determines whether the alteration occurs before or after noting the value of the operand. They were not in the earliest versions of B, but appeared along the way. People often guess that they were created to use the auto-increment and auto-decrement address modes provided by the DEC PDP-11 on which C and Unix first became popular. This is historically impossible, since there was no PDP-11 when B was developed. https://www.bell-labs.com/usr/dmr/www/chist.html thereby alleviating the need for Ken to chime in (although they do allow a very efficient implementation of it). Too much to hope for, I guess. Noel

3 years, 7 months

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Re: [TUHS] PL/I stuff - was: Book Recommendation

by jnc＠mercury.lcs.mit.edu

> From: "Charles H. Sauer"k <sauer(a)technologists.com> > I haven't done anything with 9 ktrack tapes for a long time ... > I don't recall problems reading any of them. ... > IMNSHO, it all depends on the brand/formulation of the tape. I've been > going through old audio tapes and digitizing them The vintage computer community has considerable experience with old tapes; in fact Chuck Guzis has a business reading them (which often includes converting old file formats to something modern software can grok). We originally depended heavily on the work of the vintage audio community, who pioneered working with old tapes, including the discovert of 'baking' them to improve their mechanical playability. ("the binder used to adhere the magnetic material to the backing ... becomes unstable" - playing such a tape will transfer much of the magnetic material to the head, destroying the tape's contents.) It's amazing how bad a tape can be, and still be readable. I had a couple of dump tapes of the CSR PWB1 machine at MIT, which I had thoughtlessly stored in my (at one period damp) basement, and they were covered in mold - and not just on the edges! Chuck had to build a special fixture to clean off the mold, but we read most of the first tape. (I had thoughtfully ade a second copy, which read perfectly.) Then I had to work out what the format was - it turned out that even though the machine had a V6 filesystem, my tape was a 'dd' of a BSD4.1c filesystem (for reasons I eventually worked out, but won't bore you all with). Dave Bridgham managed to mount that under Linux, and transform it into a TAR file. That was the source of many old treasures, including the V6 NCP UNIX. Noel

3 years, 7 months

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PL/I stuff - was: Book Recommendation

by Douglas McIlroy

> What, if any, features does PL/I have that are not realized in a modern language? Here are a few dredged from the mental cranny where they have mouldered for 50+ years. 1. Assignment by name. If A and B are structs (not official PL/I terminology), then A + B A = B copies similarly named fields of B to corresponding fields in A. 2. Both binary and decimal data with arithmetic rounded to any specified precision. 3. Bit strings of arbitrary length, with bitwise Boolean operations plus substr and catenation. 4. A named array is normally passed by reference, as in F(A). But if the argument is not a bare name, as in F((A)), it is passed by value. 5. IO by name. On input this behaves like assignment from a constant, with appropriate type conversion. 6. A SORT statement. 7. Astonishingly complete set of implicit data conversions. E.g. if X is floating-point and S is a string, the assignment X = S works when S = "2" and raises an exception (not PL/I terminology) when S = "A". My 1967 contribution to ACM collected algorithms exploited 3 and 4. I don't know another language in which that algorithm is as succinct. Doug

3 years, 7 months

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Re: [TUHS] 9-track tape (was PL/I stuff)

by Paul Winalski

DEC's VAX/VMS group got a customer bug report that was accompanied by a 9-track tape containing the programs and data necessary to reproduce the problem. When the engineer mounted the tape, it contained completely different data. He tried a different tape drive and this time he got the expected data. It turned out that the customer had reused the tape and recorded the reproducer at 1600 bpi on top of previous data recorded at 800 bpi. If the tape was mounted such that the drive didn't see the PE burst, it could still read the NRZI-encoded 800 bpi data. -Paul W.

3 years, 7 months

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Re: [TUHS] Book Recommendation

by Douglas McIlroy

The following remark stirred old memories. Apologies for straying off the path of TUHS. > I have gotten the impression that [PL/I] was a language that was beloved by no one. As I was a designer of PL/I, an implementer of EPL (the preliminary PL/I compiler used to build Multics), and author of the first PL/I program to appear in the ACM Collected Algorithms, it's a bit hard to admit that PL/I was "insignificant". I'm proud, though, of having conceived the SIGNAL statement, which pioneered exception handling, and the USES and SETS attributes, which unfortunately sank into oblivion. I also spurred Bud Lawson to invent -> for pointer-chasing. The former notation C(B(A)) became A->B->C. This was PL/I's gift to C. After the ACM program I never wrote another line of PL/I. Gratification finally came forty years on when I met a retired programmer who, unaware of my PL/I connection, volunteered that she had loved PL/I above all other programming languages. Doug

3 years, 7 months

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IBM Unix

by Ron Natalie

I remember getting an early RT without being given the root password. Now there hadn’t been too many Unix boxes I wasn’t able to break into. The Rt you could turn the key to the wrench symbol and get into the maintenance menus. Selecting to view some document which was displayed with more and that you could bang a root shell out of. > On Nov 24, 2021, at 14:42, Clem Cole <clemc(a)ccc.com> wrote: > > > > >> On Wed, Nov 24, 2021 at 1:43 PM Larry McVoy <lm(a)mcvoy.com> wrote: >> SMIT - just say no. > There were a number of things IBM did well with AIX so I'm not quite so glib knocking everything from them. > >

3 years, 7 months

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Re: [TUHS] Book Recommendation

by Norman Wilson

Larry McVoy: Say hi to Barry for me, I knew him back in the UUCP days, he was always pleasant. ==== And for me. Knew him back in my DECUS days. Also tell him that since he runs the World, it's all his fault. Norman Wilson Toronto ON

3 years, 7 months

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Two anecdotes

by Alan Glasser

Here are two anecdotes that Doug suggested I share with TUHS (I am new to TUHS, having joined just last month). *First*: *The creation of access(2).* [Marc Rochkind documented a version of this on page 56 of his book *Advanced Unix Programming* (1985, First Edition) discussing link(2). The footnote on that page says "Alan L. Glasser and I used this scheme to break into Dennis Ritchie and Ken Thompson's system back in 1973 or 1974."] Doug pointed out that the timing was probably later, as access(2) was not in the Sixth Edition release, but probably right after the release (after May 1975?). It arose from a discussion I was having with Marc, with whom I worked on SCCS and other PWB tools. We were discussing some mechanism that would require moving directories (actually, simple renaming) in a shell procedure. I told Marc that only root could make links to directories or unlink directories, but he told me that he has renamed directories with the mv command. I said then mv must be setuid to root, so we looked, and, of course, it was. I then looked at the source code for mv and quickly saw that there was no attempt to check permission on the real uid. So I told Marc it would allow anyone to become root. He wanted to see it in action, so I logged into research (I don’t remember what our organization's shared login was). No one in our organization had root access on research. Marc and I didn't have root access on our organization's machines; Dick Haight et. al. didn't share that privilege (Dick was the manager of the super-users). I think the actual sequence of commands was: cd / cp etc/passwd tmp ed tmp/passwd 1s/^root:[^:]*:/root::/ w q mv etc etc2 mv tmp etc su mv etc tmp mv etc2 etc mv etc/as2 etc/.as2 {logout, hangup and wonder} The last bit was a test to see what was noticed about what I did. Marc and I talked for a while about it and discussed if we had any need to be root on our local machines, but couldn't think of any pressing need, but knowing we could was a bit of a comfort. After a short time, Marc suggested logging back in to see what, if anything, had been done. /bin/mv had lost setuid to root /etc/as2 was restored /etc/.as2 was nonexistent And the next day, the motd on research mentioned that there's a new syscall: access. And mv(1) now used it. *Second*: Our organization was one (out of possibly others) subject of Ken's *codenih* that he documented in his Turing Award article in CACM. As previously described, root access was closely guarded in the PWB organization and, according to Doug, freely available in research. Ken had given us a login that was shared by PWB development and we had given Ken a login to our systems. We had no root access on research and Ken had no root access on our systems. Our C compiler guy, Rich Graveman, who kept in close contact with Dennis and was always getting us the latest compiler to install, had gone to MH and came back with a tape of a new compiler. Rich, being a careful fellow, did a size on c0, c1, c2 on the files from the tape and did the same on the running compiler pieces in /lib. Lo and behold, he discovered that the new compiler from Dennis was smaller than the old compiler even though it had a whole new feature (I think it was union). So Rich did nm's on the two different c0's and discovered a name "codenih" in the old compiler that wasn't in the new one from Dennis. He logged into research, cd'ed to /usr/ken and did an ls -ld codenih, followed by a cd codenih. Was he surprised! Then he went back to a local machine and tried to login as root/codenih, which, of course, worked. He was even more surprised and told a number of colleagues, myself included. (I logged into research and printed out the source in /usr/ken/codenih. I was super impressed.) I think you misunderstood the codenih bit. As Ken had given us a (shared among a few of us) login, we had given him one. And Dick Haight refused him root access. And no one in PY had root access on research. So much for denying Ken root access on the PWB systems. Ken "infected" the PWB C compiler with codenih, which gave him free rein. I don't know how or when he first installed it, but I suspect he was aware of any extant security holes (e.g., the mv setuid root) to allow him to replace the compiler the first time. I don't know if the PWB crowd was the impetus for Ken writing codenih or if it was something he had used on others prior to us or if he ever used it on anyone else. Needless to say, Dick Haight was beside himself. I just thought it was a great feat of programming and was thrilled when he described it in CACM. Alan

3 years, 7 months

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Re: [TUHS] Recreation of the PDP-7 UNIX TMG compiler compiler

by Douglas McIlroy

> I was deeply motivated by TMG. The good news is that you could say what > you wanted and it just did it. The bad news was the error handling. > Because it was recursive if you made a syntax error the program > backtracked and tried again. And again. And again. And eventually was > back at the first character of the input with nowhere to go. So it > issued one of its two messages -- "Syntax Error". This is somewhat of a caricature. If one's compilation strategy were to build an abstract syntax tree of the whole source program before emitting any object code, then things would go as Steve describes. In reality, TMG wasn't used this way. For one thing, ASTs needed too much memory. In TMG one could emit code while parsing. Typically code was generated on a statement-by-statement basis. This limited the backtracking, so even a naive "syntax error" diagnostic could be localized to the statement level. Long-distance connections, such as the branch labels in a nest of if statements, could nevertheless be realized recursively. Thus, in actual use, a TMG "grammar" was partly a parsing program and partly abstract specification. The balance of viewpoints was left to the discretion of the grammar's author. Yacc swung the pendulum toward the abstract. Doug

3 years, 7 months

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> Who asked Ken for grep?

by Douglas McIlroy

I can say unequivocally that I asked Ken for grep, and the next day it was in /bin. But ... I understand now that grep already existed in /usr/ken/bin. My request was the last straw that tipped the balance from private to public. Hopefully Ken can answer whether he made it originally for himself or for Lee. Doug

3 years, 7 months

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Re: [TUHS] Book Recommendation [ reallly inscrutable languages ]

by Nelson H. F. Beebe

The discussions under this subject line have somewhat strayed from Unix heritage issues, but because several people have contributed views of assorted programming languages that mostly grew up on Unix-family systems, I decided to add this memory. Several years ago, I attended a talk by Dan McCracken (1930--2011), noted book author in computer areas, and VP and later President of the ACM (1978--1980). His talk was about programming languages, and was done in a question/answer format, with Dan offering both parts. He began: Q: In 10 years, which of the following programming languages will still be in use: Basic, Cobol, Fortran, PL/I, .... A: First of all, Basic is not a programming language. Then ... ------------------------------------------------------------------------------- - Nelson H. F. Beebe Tel: +1 801 581 5254 - - University of Utah FAX: +1 801 581 4148 - - Department of Mathematics, 110 LCB Internet e-mail: beebe(a)math.utah.edu - - 155 S 1400 E RM 233 beebe(a)acm.org beebe(a)computer.org - - Salt Lake City, UT 84112-0090, USA URL: http://www.math.utah.edu/~beebe/ - -------------------------------------------------------------------------------

3 years, 7 months

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Fwd: Who asked Ken for grep?

by silas poulson

Hello, I tried asking question below awhile back - would anyone know the proper answer? Many Thanks, Silas > > Hello, > > Recently watched couple of videos[1][2] from Ken and Brian Kernighan > on the origin of grep. > > In [1], Brian suggests Lee McMahon asked Ken for grep to help with > federalist papers analysis. > > However Ken states in [2] that Doug Mcllroy asked for someway to “look > for things in files”. > > Is this just Brian misremembering or multiple people asking around similar > times? > > Many thanks, > Silas > > [1]Where GREP Came From - Computerphile > <youtube.com/watch?v=NTfOnGZUZDk> > > [2]VCF East 2019 -- Brian Kernighan interviews Ken Thompson > <https://www.youtube.com/watch?v=EY6q5dv_B-o>

3 years, 7 months

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Re: [TUHS] Book Recommendation [ reallly inscrutable languages ]

by Paul Ruizendaal

Here’s another angle on Perl, perhaps more on topic for TUHS. Let’s accept for a minute that Perl filled the void between C and shell scripts, and that there was a latent need for a scripting language like this on Unix. The shell, awk, sed, etc. had arrived at more or less fully formed versions by 1980. Perl (and TCL) did not appear until the very end of the 1980’s. What filled the gap in that decade, if anything? Ancient Unix has ‘bs’ https://en.wikipedia.org/wiki/Bs_(programming_language) but this seems to have had very little use. Paul

3 years, 7 months

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Recreation of the PDP-7 UNIX TMG compiler compiler

by Phil Budne

I was a member of the team that typed in scans of PDP-7 UNIX (the first batch of scans done didn't include the shell, so I cobbled one together in March of 2016). Scans of a second batch of listings turned up and were entered two years ago (October 2019), including the original shell, and appeared to be part of Doug McIlroy's implementation of TMG (TransMoGrifier), the compiler compiler first used to implement B. In January 2020 we got confirmation that the files t1.s thru t8.s were, in fact, for TMG, but that we were missing the compiler for the TMGL language, written in TMGL and the generated code. In what is perhaps best described as a crazed act, over the past two months I've worked to recreate a working TMG environment on PDP-7 UNIX, including a B compiler in TMGL, currently available at: https://github.com/philbudne/pdp7-unix/tree/tmg A good starting place is https://github.com/philbudne/pdp7-unix/blob/tmg/misc/tmg-notes.txt which started as my collected notes, questions and findings, and I've expanded it with prose, observations and thoughts that could, at least conceivably, be of interest to those not as oriented towards self-punishment as I am. (and on that topic, if you're looking for someone to expand, contract, or otherwise deal with some seemingly intractable legacy code, let me know: http://www.regressive.org/phil/resume.html)

3 years, 7 months

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Re: [TUHS] Book Recommendation

by Douglas McIlroy

>>I take credit as a go-between, not as an inventor. Ken Knowlton >>introduced the notation ABC in BEFLIX, a pixel-based animation >>language. > In BEFLIX, 'ABC' meant what, exactly? Offsets from pixel locations? It meant exactly what A->B->C means in C. Pixels had properties, represented in data structures. One valid data type was pointer. Incidentally, another BEFLIX innovation was the buddy system for dynamic storage allocation. Doug

3 years, 7 months

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Re: [TUHS] Book Recommendation

by Douglas McIlroy

While waiting to see the full text, I've poked around the index for subjects of interest. It certainly is copious, and knows about a lot of things that I don't. The authors make a reasonable choice in identifying the dawn of "modern computing" with Eniac and relegating non-electronic machines to prehistory. Still, I was glad to find the prophetic Konrad Zuse mentioned, but disappointed not to find the Bell Labs pioneer, George Stibitz. Among programming languages, Fortran, which changed the nature of programming, is merely hinted at (buried in the forgettable Fortran Monitoring System), while its insignificant offspring PL/I is present. (Possibly this is an indexing oversight. John Backus, who led the Fortran project, is mentioned quite early in the book.) Algol, Lisp, Simula and Smalltalk quite properly make the list, but Basic rates more coverage than any of them. C, obscurely alphabetized as "C language", is treated generously, as is Unix in general. Surprisingly there's almost nothing in the index about security or privacy. The litany of whiggish chapters about various uses of computers needs a cautionary complement. "The computer attracts crooks and spies" would be a stylistically consistent title. Doug

3 years, 7 months

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Re: [TUHS] Book Recommendation [ reallly inscrutable languages ]

by Douglas McIlroy

> My belief is that perl was written to replace a lot of Unix pipelines, I understand Perl's motive to have been a lot like PL/I's: subsume several popular styles of programming in one language. PL/I's ensemble wasn't always harmonious. Perl's was cacophony. Doug

3 years, 7 months

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Re: [TUHS] Book Recommendation

by John Foust

At 11:00 AM 11/16/2021, Douglas McIlroy wrote: >>> The former notation C(B(A)) became A->B->C. This was PL/I's gift to C. > >> You seem to have a gift for notation. That's rare. Curious what you think of APL? > >I take credit as a go-between, not as an inventor. Ken Knowlton >introduced the notation ABC in BEFLIX, a pixel-based animation >language. In BEFLIX, 'ABC' meant what, exactly? Offsets from pixel locations? - John

3 years, 7 months

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Speaking of groups: JHU Ownership

by Ron Natalie

A private message with Uh, Clem reminds me of another quaint piece of UNIX group history: JHU Ownership. The original V6 kernel and file systems used a char for UID and GID. This meant that you could only have 255 (plus the root user) distinct users on the machine. The JHU PDP-11/45 was used for the EE classes and we had more than that many users. The kernel was modified to check if the GID was 200 or greater. If it was, that was taken along with the UID to be part of the user identity. We gave all the class accounts such GIDs. Of course, we had to be careful about newgrp and fun and games with setuid/setgid (both the system call and the bits on the executables). I spent a lot of my time looking for exploits there and fixing them once I (or someone else) found them.

3 years, 7 months

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Will someone please explain the history and usage of gpasswd / newgrp / sg?

by Grant Taylor

Hi, Will someone please explain the history and usage of gpasswd / newgrp / sg? I've run across them again recently while reading old Unix texts. I've been aware of them for years, but I've never actually used them for anything beyond kicking the tires. So I figured that I'd inquire of the hive mind that is TUHS / COFF. When was the concept of group passwords introduced? What was the problem that group passwords were the solution for? How common was the use of group passwords? I ran into one comment indicating that they used newgrp to work around a limitation in the number of (secondary) groups in relation to an NFS implementation. Specifically that the implementation of NFS they were using didn't support more than 16 groups. So they would switch their primary group to work around this limit. Does anyone have any interesting stories related to group passwords / gpasswd / newgrp / sg? -- Grant. . . . unix || die

3 years, 7 months

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Double posting

by jnc＠mercury.lcs.mit.edu

Can people **please** send posts to one of these two lists, only? Having to go through and delete every other post (yeah, I know, I could relete _all_ messages to either list, since they are archived, but old habits are hard to break) is _really_ annoying. OK, I can see sending an _initial_ query to both lists, to get it to as wide a circle as possible: _but_ BCC at least one of them, to prevent lazy people just hitting 'reply all' and thereby sanding out multiple copies of their reply. Thank you. Noel

3 years, 7 months

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Book Recommendation

by Clem Cole

I wanted to pass on a recommendation of a new book from MIT Press called: “A New History of Computing” by Thomas Haigh and Paul Cerruzzi, ISBN 978-0-262-54299-0 Full disclosure, I reviewed a bit of it for them and have been eagerly awaiting final publication. I do expect a lot of the readers of this mailing list will enjoy it. They did a super job researching it and it’s very complete and of course, interesting. FWIW: the work of a number people that are part of this list is nice chronicled. Clem -- Sent from a handheld expect more typos than usual

3 years, 7 months

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First(?) C Reference Manual

by Alan Glasser

I have been looking for some time for a C Reference Manual from early 1973 (or late 1972) where Dennis comments that multiple array subscripts will eventually have Fortran-like syntax with commas separating rather than multiple sets of square brackets. That was the first C manual I had back when I first learned the language. Silly me, I discarded it when a newer one was issued, not realizing the historical significance of the earlier one. - Alan

3 years, 7 months

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Re: [TUHS] macro returning a value?

by Douglas McIlroy

> Is there a trick to make a macro or string return a value? I know what you mean. Though a string does return a value, it can't compute an arithmetic result. Alternatively, a macro, which can use arithmetic, can only return the result as a distinct input line. (That might be overcome by a trick with \c, but I don't see one right off.) Though I have no useful advice about this dilemma, it does spur memories. I wrote the pre-Unix roff that was reimplemented on Unix and then superseded by Joe Ossanna's nroff. Joe introduced macros. Curiously, I had implemented macros in an assembler so early on (1959) that I have (incorrectly) been cited as the father of macros, yet it never occurred to me to put them in roff. Joe's work inspired me to add macros to pre-Unix roff. I did one thing differently. A macro could be called the usual way or it could be called inline like an nroff string. The only difference was that a macro's final newline was omitted when it was expanded inline. That implementation might have helped with the dilemma. Doug

3 years, 7 months

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retro-fuse support for v7 filesystems

by Jay Logue

Just a quick note to announce that the retro-fuse project now supports mounting seventh-edition file systems for read and write on Linux and MacOS. As was done for v6, the project incorporates the actual filesystem code from v7 Unix, lightly modernized to run in user space on current systems. The code is available on github for anyone who's interested: https://github.com/jaylogue/retro-fuse --Jay

3 years, 8 months

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First Edition 50th publication anniversary...

by Perry E. Metzger

According to https://www.bell-labs.com/usr/dmr/www/1stEdman.html : The first edition of the Unix Programmer's Manual was dated November 3, 1971 So, Happy 50th Birthday, First Edition! Perry

3 years, 8 months

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Question about Unix adminstration

by joseph turco

Hello all, I was wondering if there exists a book on Unix administration, specifically for v7. I have the Unix programmers book already. Regards Joseph Turco

3 years, 8 months

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Re: [TUHS] Unix NCP protocol stack for ARPANET

by jnc＠mercury.lcs.mit.edu

> From: "Ron Natalie" > However, the last NCP host table shows this statistic for DEC machines > on the NCP Arpanet > ... > PDP11 (MOS): 11 > PDP11 (MINITS); 10 Hi, which host table was this that you're looking at? I'm pretty sure there was no MINITS NCP ('NCP' in the sense of 'Initial Connection Protocol (ICP)' and 'ARPANET Host-to-Host Protocol (AHHP)' - see below). There was _certainaly_ no MINITS machine on the ARPANET at MIT (the birthplace of MINITS). To confirm, I looked at a major MINITS source repository, here: https://github.com/PDP-10/its/tree/master/src/mits_s and saw nothing like that. (Not even an 1822 interface driver.) If you look there, you _will_ see things labelled 'NCP', but this is just a terminological affliction among the CHAOS people, to whom 'NCP' apparently meant 'protocol implementation' or 'network code'. Also, implementations of the 'Host-to-IMP Protocol (HIP)' are _not_ NCP either; there was an HIP implementation in the C Gateway, but that was as IP router, one that could connect to an IMP. IF IT DOESN'T HAVE AHHP, IT"S NOT NCP. Also, I was intimately familiar with MOS, and neither of the two earliest applications that ran on it (the TIU, and the Port Expander, both of which I have the source code for) had any NCP. I looked at a lot of the MOS 'NCP" listings in a old host table (see here: https://gunkies.org/wiki/Talk:Network_Control_Program for details) and concluded that the MOS 'NCP' entries were all 'confused'. > From: Clem Cole > I was under the impression, that you folks at MIT did a ChaosNet > interface, IIRC, so there may have been some sort of conversion on > your LAN, but I really doubt there was a real NCP running. The AI Lab did both i) a LAN called CHAOS (4 Mbit/seccond CSMA-CD over CATV cable) and ii) a protocol family callled CHAOS (which later ran over XDI Ethernet). I'm not sure that any of it has any relvance to what's under discussion here. > But there was a Rand stack around the same time and III think > Holmgren ended up at UCSB after his time at UICI. Im fairly sure there > was cross polinartion but I don't know how much. I looked through my V6 Unix NCP, but although there were some RAND #ifdefs, I didn't see anything about Rand (except that the MMDF is noted as being based on something done at Rand). I retain the distinct impression that all V6 Unix NCP machines were running some descendant of the UIUC code. NOSC seems to have served as a distro center at one point, see: https://minnie.tuhs.org//cgi-bin/utree.pl?file=SRI-NOSC/new/dist.log but I can't tell who they were sending it too. (We never tried to get it running at MIT since we were out of IMP ports. By the time we got another IMP, we had IP running on the -11 and NCP was done anyway.) As for UCB, there are a bunch of UCBUFMOD #ifdef's, not sure what that was about. > As for other NCPs, PARC had MAXC on the net, but I thought it had > originally a DG Nova front end that was replaced with an Alto. No, Maxc1 had a Nova, Maxc2 had an Alto. > From: Paul Ruizendaal > they started with 32V in the Fall of 1979, and ported UIUC's NCP code > to it Thanks for straightening that out. I had a vague memory that there were a few VAXen that ran NCP, but wasn't sure. > 2. Note that the BBN TCP worked over NCP as its primary transport. Your terminology is confused. TCP _never_ ran 'on' NCP; they were _alternative_ protocol stacks on top of IHP (on the ARPANET). No AHHP, no NCP. > The driver is still there if you look That acc.c is a driver for the ACC 1822 interface; it includes bits of IHP ("Try to send 3 no-ops to IMP") but I don't think it includes the complete IHP. There are other BSD 1822 device drivers, e.g.: https://minnie.tuhs.org/cgi-bin/utree.pl?file=2.11BSD/sys/pdpif/if_sri.c That's the BSD2.11 Stanford/SRI 1822 device driver. Noel

3 years, 8 months

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Anyone have a modem wired up?

by John Floren

I'm experimenting with my PiDP-11; I think I may have my modem set up properly to accept incoming calls, but with only one phone line I'm unable to test it. If anyone with a modem is willing to help me test, send me a message off-list and I'll give you my phone number & some login details. john

3 years, 8 months

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Motorola System V/68 preservation?

by Chris Hanson

Has anyone other than the owner of m88k.com preserved Motorola System V/68? Besides that, there’s the SVR1 (v2.8) for the Motorola VME/10 on Bitsavers and that’s about it. I’m especially curious as to whether anyone has preserved the SVR2 1.1 binary+sources distribution, since there might be useful information in it—or derivable from it—about much of the early VME hardware. — Chris Sent from my iPad

3 years, 8 months

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Re: [TUHS] Unix NCP protocol stack for ARPANET

by Paul Ruizendaal

Noel wrote: >> 2. Note that the BBN TCP worked over NCP as its primary transport. > > Your terminology is confused. TCP _never_ ran 'on' NCP; they were > _alternative_ protocol stacks on top of IHP (on the ARPANET). No > AHHP, no NCP. Yes, of course you are right. I meant BBN TCP used *Arpanet* as its primary transport and hence has drivers for the IMP interface hardware. Lars wrote: > Here's the rub. Some hosts may have jumped the TCP/IP gun ahead of the > 1/1 1983 flag day. The host tables don't say. Could it be that all > those VAXen were running experimental TCP/IP in January 1982? From Mike Muuss’ TCP digest mailing list and a mail conversation with Vint Cerf a few years ago I understood the following. “Flag day” wasn’t as black and white as we remember it now. During 1982 there was a continuous push to move systems to TCP, and over the year more and more systems became dual protocol capable and later even TCP only. Because all TCP traffic used the same, dedicated Arpanet link number, BBN’s network control team could monitor the level of usage. From memory, in the Summer of 1982 traffic was about 50% TCP and by October 70%. Presumably it reached 80-90% by the end of the year. During 1982 on 3 occasions, network control activated a feature in the IMP’s that refused traffic on link #0, which NCP used to negotiate a connection. This caused NCP applications to stop working. Again from memory, the first outage was a few hours, the second one a day and third one, late in 1982, for two days. This highlighted systems that needed conversion and helped motivate higher ups to approve conversion resources. It seems that making the switch often involved upgrading PDP11 to VAX. From what I can tell flag day went well, although there were issues with mail gateways that lasted for several weeks. At the start of 1982 there was no (usable) VAX Unix TCP code that I am aware of. There were several options for the PDP11, but of those I think only the 3COM code worked well. Around March/April there was code from BBN (see TUHS 4.1BSD) and from CSRG (4.1a BSD). A special build of PDP11 2.8BSD with TCP arrived somewhat later. My impression is that this was still the state of play on flag day, with 4.1cBSD only arriving well into 1983.

3 years, 8 months

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Re: [TUHS] Unix NCP protocol stack for ARPANET

by Paul Ruizendaal

> I have searched the TUHS archive and elsewhere, but all I > find for Unix is a copy of the PDP-11 Unix V6 NCP from Illinois. > > Has any other NCP implementation for Unix survived? From old host > tables I think there may have been some VAXen online before the switch > to TCP/IP. Lars, You may want to look at the 4 surviving BBN tapes on Kirk McKusick’s DVD software collection. A small part of that is on the TUHS Unix tree page - see the 4.1BSD entry. 1. A history of NCP on the VAX at BBN can be found in the change log: https://www.tuhs.org/cgi-bin/utree.pl?file=BBN-Vax-TCP/history In short they started with 32V in the Fall of 1979, and ported UIUC’s NCP code to it in May 1980. They then moved to 4.1BSD in August and ported yet again. It would seem that the ports were fairly straightforward. Coding for TCP begins in January 1981. 2. Note that the BBN TCP worked over NCP as its primary transport. The driver is still there if you look through the surviving BBN tapes. Part of that code is on TUHS: https://www.tuhs.org/cgi-bin/utree.pl?file=BBN-Vax-TCP/dev/acc.c https://www.tuhs.org/cgi-bin/utree.pl?file=BBN-Vax-TCP/bbnnet-oct82/imp_io.c It will take some effort, but probably the NCP VAX code can be reconstructed from the surviving PDP11 UIUC code and these BBN tapes (the file names in the change log match). 3. The BBN tapes also have some user level software: telnet, ftp, mtp. This code consists of straight NCP to TCP conversions and the source code has #ifdef’s for NCP and TCP. An example is here: https://www.tuhs.org/cgi-bin/utree.pl?file=BBN-Vax-TCP/src/telnet/netser.c Hope this helps. Paul PS - Info on the DVD is here (bottom of the page): https://www.mckusick.com/csrg/

3 years, 8 months

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Unix NCP protocol stack for ARPANET

by Lars Brinkhoff

Hello, I'm working on setting up an emulated ARPANET using the original IMP software recovered some years ago. It turns out, the greatest challenge is finding the NCP software on the host side that implements the ARPANET protocols. I have searched the TUHS archive and elsewhere, but all I find for Unix is a copy of the PDP-11 Unix V6 NCP from Illinois. Has any other NCP implementation for Unix survived? From old host tables I think there may have been some VAXen online before the switch to TCP/IP. Best regards, Lars Brinkhoff

3 years, 8 months

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having issues with simh and setting up dci for unixV7

by joseph turco

hello all, i am a new unix user, so please excuse my ignorance. I am trying to setup using unixV7 with simh pdp11 emulator. The guide i am following is by Will Senn (in PDF form). I have been able to successfully get the machine to boot with unix, and login as root. what i am having problems with, is trying to get telnet access via dci to work. when i follow the guide and do the following: # cd /usr/sys/conf # rm l.o c.o # cp hptmconf myconfnf # echo 4dc >> myconf # mkconf < myconf # make as - -o l.o l.s cc -c c.c ld -o unix -X -i l.o mch.o c.o ../sys/LIB1 ../dev/LIB2 # sum unix 10314 106 # ls -l unix -rwxrwxr-x 1 root 54122 Dec 31 19:09 unix etc... when i issue the mkconf < myconf command, i get a bunch of text printed out, but with a 'root device not found'. the sum unix value is different, as well as the size of the ls -l unix file size.. now when i try booting it with the newly created mboot.ini file (as per the guide), i go to start up the system with 'hp(0,0)munix' and it starts but hangs with the text 'fault devtab' what am I doing wrong? regards, Joseph Turco

3 years, 8 months

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Minix 1.5 updates/patches?

by Chris Hanson

I’ve gotten Minix 1.5 up and running on Hatari, the Atari ST emulator, and I’d like to update it to the latest in the 1.5 series (1.5.10.7). The patch sets used to be quite readily available, but the only patch sets I’ve been able to find have been the 1.5.10.3 to 1.5.10.4 patches posted to Usenet (via minnie, thanks!) which won’t apply cleanly to my sources because I’m only running 1.5. (I know about the 1.6.25-on-Atari efforts, I’m trying to do something different and also fill in some git history…) — Chris

3 years, 8 months

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mmap origin (was Systematic approach to command-line interfaces)

by Paul Ruizendaal

On Wed, Sep 29, 2021 at 09:40:23AM -0700, Greg A. Woods wrote: > I think perhaps the problem was that mmap() came too soon in a narrow > sub-set of the Unix implementations that were around at the time, when > many couldn't support it well (especially on 32-bit systems -- it really > only becomes universally useful with either segments or 64-bit and > larger address spaces). The fracturing of "unix" standards at the time > didn't help either. > > Perhaps these "add-on hack" problems are the reason so many people think > fondly of the good old Unix versions where everything was still coming > from a few good minds that could work together to build a cohesive > design. The add-ons were poorly done, not widely implemented, and > usually incompatible with each other when they were adopted by > additional implementations. mmap() did come from those days and minds. The first appearance of mmap() was in 32V R3, done by John Reiser in 1981. This is the version of 32V with full demand paging; it implemented a unified buffer cache. According to John, that version of mmap() already had the modern 6 argument API. John added mmap() because he worked with Tenex a lot during his PhD days and missed PMAP. He needed some 6 months to design, implement and debug this version of 32V as a skunkworks project. I am trying to revert early VAX SVr1/r2 code to get a better view of what 32V R3 looked like, but unfortunately I did not have much time for this effort in last couple of months. It would seem that 32V R3 assumed that disk blocks and memory pages were the same size (true on a 1980 VAX) and with that assumption a unified buffer cache comes natural in this code base. For 4.2BSD initially Joy cs. had a different approach to memory mapped files in mind (see the 1981 tech report #4 from CSRG). By the time of 4.2BSD’s release the manual defined a mmap() system call, but it was not implemented and it appears to have been largely forgotten until SunOS 4 and dynamic libraries six years later. In the SysV lineage it is less clear. For sure mmap() is not there, but the first implementation of the shmem IPC feature might derive from the 32V R3 code. On the inside, SVr2 virtual memory appears to implement the segments (now called regions) that Joy envisaged for 4.2BSD but did not implement. CB Unix had a precursor to shmem as well, where a portion of system core was reserved for shared memory purposes and could be accessed either via the /dev/mem device or could be mapped into the PDP-11 address space (using 1 of the 8 segment registers for each map). Here too the device and the map were unified. So far, I have not come across any shared library implementations or precursors in early Unix prior to SunOS 4. Paul

3 years, 8 months

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IEEE Annals on the History of Computing seeks Editor in Chief

by Diomidis Spinellis

Dear TUHS members, The IEEE Annals on the History of Computing magazine, the primary publication for recording, analyzing, and debating the history of computing, is seeking a new Editor in Chief [2]. The EiC term begins on January 1st 2022 and is for three years, renewable for two years. The application deadline is October 31st 2021. It would be valuable for us interested in our discipline's history to to serve in the publication's leadership. You can contact Carrie Clark at c.clark(a)computer.org to submit an application. Alternatively, if you have connections in the community and some time to spare to head the EiC selection committee, please drop me a note. [1] https://www.computer.org/csdl/magazine/an [2] https://www.computer.org/press-room/2021-news/ieee-cs-publications-seek-app… Kind regards, Diomidis Spinellis

3 years, 8 months

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RIP Jörg Schilling

by Robert Clausecker

I have received message from his family that Jörg Schilling has passed away from complications related to kidney cancer this sunday around noon (CEST). He will be remembered for his open source projects including - cdrtools, the first portable CD burning program - star, a powerful and fast tar implementation, the first to use two processes with a shared ring buffer for better performance. - smake, a make implementation with autoconf features - sformat, a versatile SCSI disk formatting program - SING, an autoconf fork with a comprehensive set of libc shims, providing a uniform API across operating systems - ved, an early visual editor for the UNOS operating system (I believe) - bosh, a carefully maintained fork of the Bourne shell - sccs, a carefully maintained fork of SCCS. His attempts to teach it projects and networking will remain unfinished. - libfind, an implementation of find(1) as a library for integration into other software. - libxtermcap, an extended termcap library - libscg, an early portable SCSI driver and library He is also remembered for his commitment to open source, portability, and his work on POSIX. He was working on adapting his software to Z/OS and introducing message catalogues just weeks before his death. Jörg worked for the Bethold typesetting company, one of the first European customers of SUN microsystems. It is there that his love for UNIX and SUN OS in particular was kindled. [1] His interest in SUN OS culminated in Schillix, one of the first open source Solaris distributions. We will of course also remember him for his flames. [1]: https://web.archive.org/web/20061201103910/http://www.opensolaris.org/os/ar… May his software immortalise him. Robert Clausecker -- () ascii ribbon campaign - for an 8-bit clean world /\ - against html email - against proprietary attachments

3 years, 8 months

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Re: [TUHS] [Haskell-cafe] Terminator syntax style (Was: Nested (=>) (Was: On finding the right exposition...))

by Norman Wilson

John Cowan: "Between each" has been part of Standard English for a thousand years, and still is today. ==== As in between each pair of elements, or between each element? The latter strikes me rather like the currently-in-vogue phrase `one of the only': it may have a defined meaning, but it sure sounds distractingly stupid. (If it's one of the group at all, it's by definition one of the only members; if what is meant is one of the few, then say so, dammit.) It's rather like obfuscated C, or nearly any use of Perl: sure, you can write it to require extra mental effort to make sense of it, but there are simpler ways to be rude. Norman Wilson Toronto ON Please, sir, I'd like to join The Few. I'm sorry, there are far too many.

3 years, 9 months

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Re: [TUHS] [Haskell-cafe] Terminator syntax style (Was: Nested (=>) (Was: On finding the right exposition...))

by Douglas McIlroy

Apropos of "finding the right exposition"!, consider the cited wiki article: Separator: There is a symbol between each element. The more carefully you read this the more it becomes nonsense. 1, "Each element" is an individual. You can't put something between an individual. 2 The defining sentence states a property of a representation of a sequence. It fails to indicate that "separator" is the symbol's role. In fact what's being defined is "separator notation", not the bare word "separator". This usage appears only later in the article. It should be employed throughout--most importantly in the title and the definition. The same goes for "terminator". Doug

3 years, 9 months

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retraction

by Douglas McIlroy

> Doug, if you insist on applying your superb editing skills on wiki material, we will never hear from you again! Thanks, Bill, for the wise advice. If I'm putting out stuff like this you shouldn't hear from me again. Apologies for again(!) posting to the wrong mailing list. Doug

3 years, 9 months

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4.3BSD-Tahoe Restoration

by Henry Bent

Hello All, I am attempting to restore 4.3BSD-Tahoe to a usable state on the VAX. It appears, based on the work that I have done already, that this is possible. Starting with stock 4.3BSD I got a source tree into /usr/tahoe and using it I replaced all of /usr/include and /sys, recompiled and replaced /bin, /lib, and /etc, recompiled a GENERIC kernel, and from there I was able to successfully reboot using the new kernel. As far as I can tell (fingers crossed!) the hardest part is over and I'm in the process of working on /usr. My question is: how was this sort of thing done in the real world? If I was a site running stock 4.3BSD, would I have received (or been able to request) updated tapes at regular intervals? The replacement process that I have been using is fairly labor intensive and on a real VAX would have been very time intensive too. Fortunately two to three years' worth of changes were not so drastic that I ever found myself in a position where the existing tools were not able to compile pieces of Tahoe that I needed to proceed, but I could easily imagine finding myself in such a place. (This was, by the way, what I ran into when attempting to upgrade from 2.9BSD to 2.10BSD, despite a fully documented contemporary upgrade procedure). -Henry

3 years, 9 months

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Groups origins

by norman＠oclsc.org

I can't speak to the evolution and use of specific groups; I suspect it was all ad-hoc early on. Groups appeared surprisingly late (given how familiar they seem now): they don't show up in the manual until the Sixth Edition. Before that, chown took only two arguments (filename and owner), and permission modes had three bits fewer. I forget how it came up, but the late Lee McMahon once told me an amusing story about their origin: Ken announced that he was adding groups. Lee asked what they were for. Ken replied with a shrug and `I dunno.' Norman Wilson Toronto ON

3 years, 9 months

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Groups origins

by norman＠oclsc.org

Groups appeared surprisingly late (given how familiar they seem now): they don't show up in the manual until the Sixth Edition. Mea culpa; read too hastily. The change actually came with the Fourth Edition, at the same time as several other landmark system changes: -- Time changing from a 32-bit count of 60Hz clock ticks (which ran out so quickly that its epoch kept moving) to the modern 32 bits of whole seconds, based at 1970-01-01T00:00:00 GMT (which takes much longer to run out, though the horizon is now visible). -- The modern super-block. In 4/e, the super-block began at block 0, not 1 (so bootstrapping was rather more complicated); the free list was a bitmap rather than the later list of blocks containing lists of free block numbers. -- The super-block contained a bitmap of free i-numbers too. All told, the free block and free i-node map made up a 1024-byte super-block. -- I-numbers 1-40 were device files; the root directory was i-number 41. The only file-type indication in the mode word was a single bit to denote directory. It was already clear that the lifetime of the bitmaps was running out: the BUGS section says two blocks isn't enough for the bitmaps for a 20-megabyte RP02. Norman Wilson Toronto ON

3 years, 9 months

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Groups origins

by Will Senn

Hi all, I was reading a recent thread, over on the FreeBSD forums about groups that quickly devolved into a discussion on the origin of the operator group: https://forums.freebsd.org/threads/groups-overview.82303/ I thought y’all would be the best place to ask the questions that arose in me during my read of the thread. Here they are in no special order: 1. Where did operator come from and what was it intended to solve? 2. How has it evolved. 3. What’s a good place to look/ref to read about groups, generally? I liked one respondent’s answer about using find, heir, and the files themselves to learn about groups being used in a running system, paying attention to the owner, Audi, etc along the way and this is how I do it now, but this approach doesn’t account for the history and evolution. Thanks! Willu Sent from my iPhone

3 years, 9 months

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Re: [TUHS] Systematic approach to command-line interfaces

by Paul Ruizendaal

Greg wrote: > I guess pipe(2) kind of started this mess, [...] Maybe I'm > going to far with thinking pipe() could/should have just been a library > call that used open(2) internally, perhaps connecting the descriptors by > opening some kind of "cloning" device in the filesystem. At times I’ve been pondering this as well. All of creat/open/pipe could have been rolled into just open(). It is not clear to me why this synthesis did not happen around the time of 7th edition; although it seems the creat/open merger happened in BSD around that time. As to pipe(), the very first implementation returned just a single fd where writes echoed to reads. It was backed by a single disk buffer, so could only hold ~500 bytes, which was probably not enough in practice. Then it was reimplemented using an anonymous file as backing store and got the modern two fd system call. The latter probably arose as a convenient hack to store the two file pointers needed. It would have been possible to implement the anonymous file solution still using a single fd, and storing the second file pointer in the inode. Maybe this felt as a worse hack at the time (the conceptual split in vnode / inode was still a decade into the future.) With a single fd, it would also have been possible to have a cloning device for pipe’s as you suggest (e.g. /dev/pipe, somewhat analogous to the implementation of /dev/stdin in 10th edition). Arguably, in total code/data size this would not have been much different from pipe(). My guess is that from a 1975 perspective, creat/open/pipe was not perceived as something that needed fixing.

3 years, 9 months

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Re: [TUHS] mmap origin (was Systematic approach to command-line interfaces)

by Paul Ruizendaal

Dan wrote: > 3BSD and I think 4.1BSD had vread() and vwrite(), which looked like > regular read() and write() but accessed pages only on demand. I was a > grad student at Berkeley at the time and remember their genesis. Bill > and I were eating lunch from Top Dog on the Etcheverry Hall plaza, and > were talking about memory-mapped I/O. I remember suggesting the actual > names, perhaps as a parallel to vfork(). I had used both TENEX and > Multics, which both had page mapping. Multics' memory-mapped segments > were quite fundamental, of course. I think we were looking for something > vaguely upward compatible from the existing system calls. We did not > leap to an mmap() right away just because it would have been a more > radical shift than continuing the stream orientation of UNIX. I did not > implement any of this: it was just a brainstorming session. Thank you for reminding me of these. On a substrate with a unified buffer cache and copy-on-write, vread/vwrite would have been very close to regular read/write and maybe could have been subsumed into them, using flags to open() as the differentiator. The user discernible effect would have been the alignment requirement on the buffer argument. John Reiser wrote that he "fretted” over adding a 6 argument system call. Perhaps he was considering something like the above as the alternative, I never asked. I looked at the archives and vread/vwrite were introduced with 3BSD, present in 4BSD but marked deprecated, and absent from 4.1BSD. This short lifetime suggests that using vread and vwrite wasn’t entirely satisfactory in 1980/81 practice. Maybe the issue was that there was no good way to deallocate the buffer after use.

3 years, 9 months

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Systematic approach to command-line interfaces

by Michael Siegel

Hello, I've recently started to implement a set of helper functions and procedures for parsing Unix-like command-line interfaces (i.e., POSIX + GNU-style long options, in this case) in Ada. While doing that, I learned that there is a better way to approach this problem – beyond using getopt(s) (which never really made sense to me) and having to write case statements in loops every time: Define a grammar, let a pre-built parser do the work, and have the parser provide the results to the program. Now, defining such a grammar requires a thoroughly systematic approach to the design of command-line interfaces. One problem with that is whether that grammar should allow for sub-commands. And that leads to the question of how task-specific tool sets should be designed. These seem to be a relatively new phenomenon in Unix-like systems that POSIX doesn't say anything about, as far as I can see. So, I've prepared a bit of a write-up, pondering on the pros and cons of two different ways of having task-specific tool sets (non-hierarchical command sets vs. sub-commands) that is available at https://www.msiism.org/files/doc/unix-like_command-line_interfaces.html I tend to think the sub-command approach is better. But I'm neither a UI nor a Unix expert and have no formal training in computer things. So, I thought this would be a good place to ask for comment (and get some historical perspective). This is all just my pro-hobbyist attempt to make some people's lives easier, especially mine. I mean, currently, the "Unix" command line is quite a zoo, and not in a positive sense. Also, the number of well-thought-out command-line interfaces doesn't seem to be a growing one. But I guess that could be changed by providing truly easy ways to make good interfaces. -- Michael

3 years, 9 months

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Re: [TUHS] Systematic approach to command-line interfaces

by Douglas McIlroy

> one other thing that SLS breaks, for data files, is the whole Unix 'pipe' > abstraction, which is at the heart of the whole Unix tools paradigm. Multics had an IO system with an inherent notion of redirectable data streams. Pipes could have--and eventually did (circa 1987)--fit into that framework. I presume a pipe DIM (device interface manager) was not hard to build once it was proposed and accepted. Doug

3 years, 9 months

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Re: [TUHS] Systematic approach to command-line interfaces

by jnc＠mercury.lcs.mit.edu

> From: Larry McVoy > If you read(2) a page and mmap()ed it and then did a write(2) to the > page, the mapped page is the same physical memory as the write()ed > page. Zero coherency issues. Now I'm confused; read() and write() semantically include a copy operation (so there are then two copies of that data chunk, and possible consistency issues between them), and the copied item is not necessarily page-sized (so you can't ensure consistency between the original+copy by mapping it in). So when one does a read(file, &buffer, 1), one gets a _copy of just that byte_ in the process' address space (and similar for write()). Yes, there's no coherency issue between the contents of an mmap()'d page, and the system's idea of what's in that page of the file, but that's a _different_ coherency issue. Or am I confused? PS: > From: "Greg A. Woods" > I now struggle with liking the the Unix concept of "everything is a > file" -- especially with respect to actual data files. Multics also got > it right to use single-level storage -- that's the right abstraction Oh, one other thing that SLS breaks, for data files, is the whole Unix 'pipe' abstraction, which is at the heart of the whole Unix tools paradigm. So no more 'cmd | wc' et al. And since SLS doesn't have the 'make a copy' semantics of pipe output, it would be hard to trivially work around it. Yes, one could build up a similar framework, but each command would have to specify an input file and an output file (no more 'standard in' and 'out'), and then the command interpreter would have to i) take command A's output file and feed it to command B, and ii) delete A's output file when the whole works was done. Yes, the user could do it manually, but compare: cmd aaa | wc and cmd aaa bbb wc bbb rm bbb If bbb is huge, one might run out of room, but with today's 'light my cigar with disk blocks' life, not a problem - but it would involve more disk traffic, as bbb would have to be written out in its entirety, not just have a mall piece kept in the disk cache as with a pipe. Noel

3 years, 9 months

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Re: [TUHS] Systematic approach to command-line interfaces

by jnc＠mercury.lcs.mit.edu

> From: "Greg A. Woods" > the elegance of fork() is incredible! That's because in PDP-11 Unix, they didn't have the _room_ to create a huge mess. Try reading the exec() code in V6 or so. (I'm in a bit of a foul mood today; my laptop sorta locked up when a _single_ Edge browser window process grew to almost _2GB_ in size. Are you effing kidding me? If I had any idea what today would look like, back when I was 20 - especially the massive excrement pile that the Internet has turned into - I never would have gone into computers - cabinetwork, or something, would have been an infinitely superior career choice.) > I now struggle with liking the the Unix concept of "everything is a > file" -- especially with respect to actual data files. Multics also got > it right to use single-level storage -- that's the right abstraction Well, files a la Unix, instead of the SLS, are OK for a _lot_ of data storage - pretty much everything except less-common cases like concurrent access to a shared database, etc. Where the SLS really shines is _code_ - being able to just do a subroutine call to interact with something else has incredible bang/buck ratio - although I concede doing it all securely is hard (although they did make a lot of progress there). Noel

3 years, 9 months

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Thompson trojan put into practice

by Douglas McIlroy

>> > It's part of my academic project to work on provable compiler security. >> > I tried to do it according to the "Reflections on Trusting Trust" by Ken >> > Thompson, not only to show a compiler Trojan horse but also to prove that >> > we can discover it. >> >> Of course it can be discovered if you look for it. What was impressive about >> the folks who got Thompson's compiler at PWB is that they found the horse >> even though they weren't looking for it. > I had not heard this story. Can you elaborate, please? My impression from having > read the paper (a long time ago now) is that Ken did the experiment locally only. Ken did it locally, but a vigilant person at PWB noticed there was an experimental compiler on the research machine and grabbed it. While they weren't looking for hidden stuff, they probably were trying to find what was new in the compiler. Ken may know details about what they had in the way of source and binary. Doug

3 years, 9 months

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Thompson trojan put into practice

by Douglas McIlroy

> It's part of my academic project to work on provable compiler security. > I tried to do it according to the "Reflections on Trusting Trust" by Ken > Thompson, not only to show a compiler Trojan horse but also to prove that > we can discover it. Of course it can be discovered if you look for it. What was impressive about the folks who got Thompson's compiler at PWB is that they found the horse even though they weren't looking for it. Then there was the first time Jim Reeds and I turned on integrity control in IX, our multilevel-security version of Research Unix. When it reported a security violation during startup we were sure it was a bug. But no, it had snagged Tom Duff's virus in the act of replication. It surprised Tom as much as it did us, because he thought he'd eradicated it. Doug

3 years, 9 months

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Re: [TUHS] Thompson trojan put into practice

by jnc＠mercury.lcs.mit.edu

https://googlethatforyou.com/?q=Tom%20Duff%20Virus Noel

3 years, 9 months

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Thompson trojan put into practice

by arnold＠skeeve.com

This is FYI. No comment on whether it was a good idea or not. :-) Arnold > From: Niklas Rosencrantz <niklasro(a)gmail.com> > Date: Sun, 19 Sep 2021 17:10:24 +0200 > To: tinycc-devel(a)nongnu.org > Subject: Re: [Tinycc-devel] Can tcc compile itself with Apple M1? > > > Hello! > > For demonstration purpose I put my experiment with a compiler backdoor in a > public repository > https://github.com/montao/ddc-tinyc/blob/857d927363e9c9aaa713bb20adbe99ded7… > > It's part of my academic project to work on provable compiler security. > I tried to do it according to the "Reflections on Trusting Trust" by Ken > Thompson, not only to show a compiler Trojan horse but also to prove that > we can discover it. > What it does is inject arbitrary code to the next version of the compiler > and so on. > > Regards \n

3 years, 9 months

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ATC/OSDI'21 joint keynote: It's Time for Operating Systems to Rediscover Hardware (Timothy Roscoe)

by Dan Cross

One of the things I really appreciate about participating in this community and studying Unix history (and the history of other systems) is that it gives one firm intellectual ground from which to evaluate where one is going: without understanding where one is and where one has been, it's difficult to assert that one isn't going sideways or completely backwards. Maybe either of those outcomes is appropriate at times (paradigms shift; we make mistakes; etc) but generally we want to be moving mostly forward. The danger when immersing ourselves in history, where we must consider and appreciate the set of problems that created the evolutionary paths leading to the systems we are studying, is that our thinking can become calcified in assuming that those systems continue to meet the needs of the problems of today. It is therefore always important to reevaluate our base assumptions in light of either disconfirming evidence or (in our specific case) changing environments. To that end, I found Timothy Roscoe's (ETH) joint keynote address at ATC/OSDI'21 particularly compelling. He argues that what we consider the "operating system" is only controlling a fraction of a modern computer these days, and that in many ways our models for what we consider "the computer" are outdated and incomplete, resulting in systems that are artificially constrained, insecure, and with separate components that do not consider each other and therefore frequently conflict. Further, hardware is ossifying around the need to present a system interface that can be controlled by something like Linux (used as a proxy more generally for a Unix-like operating system), simultaneously broadening the divide and making it ever more entrenched. Another theme in the presentation is that, to the limited extent the broader systems research community is actually approaching OS topics at all, it is focusing almost exclusively on Linux in lieu of new, novel systems; where non-Linux systems are featured (something like 3 accepted papers between SOSP and OSDI in the last two years out of $n$), the described systems are largely Linux-like. Here the presentation reminded me of Rob Pike's "Systems Software Research is Irrelevant" talk (slides of which are available in various places, though I know of no recording of that talk). Roscoe's challenge is that all of this should be seen as both a challenge and an opportunity for new research into operating systems specifically: what would it look like to take a holistic approach towards the hardware when architecting a new system to drive all this hardware? We have new tools that can make this tractable, so why don't we do it? Part of it is bias, but part of it is that we've lost sight of the larger picture. My own question is, have we become entrenched in the world of systems that are "good enough"? Things he does NOT mention are system interfaces to userspace software; he doesn't seem to have any quibbles with, say, the Linux system call interface, the process model, etc. He's mostly talking about taking into account the hardware. Also, in fairness, his highlighting a "small" portion of the system and saying, "that's what the OS drives!" sort of reminds me of the US voter maps that show vast tracts of largely unpopulated land colored a certain shade as having voted for a particular candidate, without normalizing for population (land doesn't vote, people do, though in the US there is a relationship between how these things impact the overall election for, say, the presidency). I'm curious about other peoples' thoughts on the talk and the overall topic? https://www.youtube.com/watch?v=36myc8wQhLo - Dan C.

3 years, 9 months

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RegExp decision for meta characters: Circumflex

by Douglas McIlroy

> Maybe there existed RE notations that were simply copied ... Ed was derived from Ken's earlier qed. Qed's descendant in Multics was described in a 1969 GE document: http://www.bitsavers.org/pdf/honeywell/multics/swenson/6906.multics-condens…. Unfortunately it describes regular expressions only sketchily by example. However, alternation, symbolized by | with grouping by parentheses, was supported in qed, whereas alternation was omitted from ed. The GE document does not mention character classes; an example shows how to use alternation for the same purpose. Beginning-of-line is specified by a logical-negation symbol. In apparent contradiction, the v1 manual says the meanings of [ and ^ are the same in ed and (an unspecified version of) qed. My guess about the discrepancies is no better than yours. (I am amused by the title "condensed guide" for a manual in which each qed request gets a full page of explanation. It exemplifies how Unix split from Multics in matters of taste.) Doug

3 years, 9 months

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Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option

by jnc＠mercury.lcs.mit.edu

> From: Roland Huisman > I have a PDP11/20 and I would love to run an early Unix version on > it. ... But it seems that the earliest versions of Unix do not need the > extra memory. Does anyone have RK05 disk images for these early Unix > versions? Although the _kernel_ source for V1 is available: https://minnie.tuhs.org//cgi-bin/utree.pl?file=V1 most of the rest is missing; only 'init' and 'sh' are available. So one would have to write almost _everything_ else. Some commands are available in PDP-11 assembler in later versions, and might be movable without _too_ much work - but one would have to start with the assembler itself, which is luckily in assembler. If I were trying to run 'UNIX' on an -11/20, I think the only reasonable choice would be MINI-UNIX: https://gunkies.org/wiki/MINI-UNIX It's basically V6 UNIX with all use of the PDP-11 memory management removed. The advantage of going MINI-UNIX is that almost all V6 source (applications, drivers, etc) will run on it 'as is'. It does need ~56KB of main memory. If you don't have that much on the -11/20, LSX (links in the above) would be an option; it's very similar to MINI-UNIX, but is trimmed down some, to allow its use on systems with less main memory. I'm not sure if MINI-UNIX has been run on the -11/20, but it _should_ run there; it runs on the -11/05, and the only differences between the /20 and the /05 are that the /20 does not have the RTT instruction (and I just checked, and MINI-UNIX doesn't use RTT), and SWAB doesn't clear the V condition code bit. (There are other minor differences, such as OP Rn, (Rn)+ are different on the -11/20, but that shouldn't be an issue.) Step 1 would be to get MINI-UNIX running on an -11/20 under a simulator; links in the above to get you there. Noel

3 years, 9 months

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Re: [TUHS] Unix for PDP11/20 w/o mmu or paging option

by jnc＠mercury.lcs.mit.edu

> From: Clem Cole > The KS11 MMU for the 11/20 was built by CSS ... I think Noel has done > more investigation than I have. I got a very rough description of how it worked, but that was about it. > I'm not sure if the KS11 code is still there. I did not think so. No, the KS11 was long gone by later Vn. Also,I think not all of the -11/20 UNIX machines had it, just some. > The V1 work was for a PDP-7 Actually, there is a PDP-11 version prior to V2, canonically called V1. The PDP-7 version seems to be called 'PDP-7 UNIX' or 'V0'. > I'm fairly sure that the RK05, used the RK11-D controller. Normally, yes. I have the impression that one could finagle RK03's to work on the RK11-D, and vice versa for RK05's on the RK11-C, but I don't recall the details. The main difference between the RK11-C and -D (other then the implementation) was that i) the RK11-C used one line per drive for drive selection (the -D used binary encoding on 3 lines), and ii) it had the 'maintenance' capability and register (al omitted from the -D). > The difference seems to have been in drive performance. Yes, but it wasn't major. They both did 1500RPM, so since they used the same pack format, the rotational delay, transfer rate, etc were identical. The one peformance difference was in seeks; the average on the RK01 was quoted as 70 msec, and 50 msec on the RK05. > Love to see the {KT11-B prints] and if you know where you found them. They were sold on eBait along with an -11/20 that allegedly had a KT11-B. (It didn't; it was an RK11-C.) I managed to get them scanned, and they and the minimal manual are now in Bitsavers. I started working on a Tech Manual for it, but gave up with it about half-way done. > I wonder if [our V1 source] had the KS-11 stuff in it. No; I had that idea a while back, looked carefully, our V1 listings pre-date the KS11. > From: Roland Huisman > There is a KT11B paging option that makes the PDP11/20 a 18 bit > machine. Well, it allows 2^18 bytes of main memory, but the address space of the CPU is still2^16 bytes. > It looks a bit like the TC11 DECtape controller. IITC, it's two backplanes high, the TC11 is one. So more like the RK11-C... :-) > I have no idea how it compares to the later MMU units from the > software perspective. Totally different; it's real paging (with page tables stored in masin memory). The KT11-B provides up to 128 pages of 512 bytes each, in both Exec and User mode. The KT11-C, -D etc are all segmentation, with all the info stored in registers in the unit. > I wonder is there is some compatibility with the KT11-B [from the KS11] I got the impression that the KS11 was more a 'base and bounds' kind of thing. Noel

3 years, 9 months

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Unix for PDP11/20 w/o mmu or paging option

by Roland

Hello Unix fanatics, I have a PDP11/20 and I would love to run an early Unix version on it. I've been working on the hardware for a while and I'm getting more and more of the pieces back online again. The configuration will be two RK05 hard disks, TU56H tape, PC11 paper tape reader/puncher and a RX01 floppy drive. Unfortunately I don't have a MMU or paging option. But it seems that the earliest versions of Unix do not need the extra memory. Does anyone have RK05 disk images for these early Unix versions? That would be a great help. Otherwise it would be great to have some input about how to create a bootable Unix pack for this machine. A bit about the hardware restoring is on the vcfed forum:https://www.vcfed.org/forum/forum/genres/dec/78961-rk05-disk-drive-ve… Booting RT11 from RK05https://youtu.be/k0tiUcRBPQATU56H tape drive back onlinehttps://youtu.be/_ZJK3QP9gRA Thanks in advance!Roland Huisman

3 years, 9 months

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RegExp decision for meta characters: Circumflex

by markus schnalke

Hoi, I'm interested in the early design decisions for meta characters in REs, mainly regarding Ken's RE implementation in ed. Two questions: 1) Circumflex As far as I see, the circumflex (^) is the only meta character that has two different special meanings in REs: First being the beginning of line anchor and second inverting a character class. Why was it chosen for the second one? Why not the exclamation mark in that case? (Sure, C didn't exist by then, but the bang probably was used to negate in other languages of the time, I think.) 2) Symbol for the end of line anchor What is the reason that the beginning of line and end of line anchors are different symbols? Is there a reason why not only one symbol, say the circumflex, was chosen to represent both? I currently see no disadvantages of such a design. (Circumflexes aren't likely to end lines of text, neither.) I would appreciate if you could help me understand these design decisions better. Maybe there existed RE notations that were simply copied ... meillo

3 years, 9 months

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Re: [TUHS] desiderata

by Douglas McIlroy

You can check the Computer History Museum's holdings on line. If they don't have the documents already, they would probably like them. The Living Computer Museum in Seattle had a working blit on display. If they don't already have the manual, I'm sure they would love to have one. Alas, their website says they've "suspended all operations for now", a result of the double whammy of Covid and the death of their principal angel, Paul Allen.

3 years, 10 months

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desiderata

by Andrew Hume

more garage cleaning this last weekend. i came across some memorabilia from my time at Bell Labs, including a lovely article titled The Electrical Properties of Infants Infants have long been known to grow into adults. Recent experiments show they are useful in applications such as high power circuit breakers. Not to mention a lovely article from the “Medical Aspects of Human Sexuality” (July 1991) titled “Scrotum Self-Repair”. the two items are 1) “Documents for UNIX Volume 1” by Dolotta, Olson and Petrucelli (jan 1981)” 2) The complete manual for the Blit. this comes in a blue Teletype binder and includes the full manual (including man pages) and circuit diagrams. i’d prefer to have them go to some archival place, but send me a private email if you interested and we’ll see what we can do. andrew

3 years, 10 months

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desiderata

by Paul Ruizendaal

I’d be interested in a scan of the Blit schematics, and it seems that a few others might be as well: https://minnie.tuhs.org/pipermail/tuhs/2019-December/thread.html#19652 https://github.com/aiju/fpga-blit (for clarity: I’m not ‘aiju') Paul > Message: 1 > Date: Wed, 8 Sep 2021 01:29:13 -0700 > From: Andrew Hume <andrew(a)humeweb.com> > To: The Eunuchs Hysterical Society <tuhs(a)tuhs.org> > Subject: [TUHS] desiderata > Message-ID: <34E984D3-AD92-402D-9A9C-E84B6362DF77(a)humeweb.com> > Content-Type: text/plain; charset=utf-8 > > more garage cleaning this last weekend. [...] > 2) The complete manual for the Blit. this comes in a blue Teletype binder and includes > the full manual (including man pages) and circuit diagrams. > > i’d prefer to have them go to some archival place, but send me a private email > if you interested and we’ll see what we can do. > > andrew

3 years, 10 months

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Is it time to resurrect the original dsw (delete with switches)?

by Jon Steinhart

I recently upgraded my machines to fc34. I just did a stock uncomplicated installation using the defaults and it failed miserably. Fc34 uses btrfs as the default filesystem so I thought that I'd give it a try. I was especially interested in the automatic checksumming because the majority of my storage is large media files and I worry about bit rot in seldom used files. I have been keeping a separate database of file hashes and in theory btrfs would make that automatic and transparent. I have 32T of disk on my system, so it took a long time to convert everything over. A few weeks after I did this I went to unload my camera and couldn't because the filesystem that holds my photos was mounted read-only. WTF? I didn't do that. After a bit of poking around I discovered that btrfs SILENTLY remounted the filesystem because it had errors. Sure, it put something in a log file, but I don't spend all day surfing logs for things that shouldn't be going wrong. Maybe my expectation that filesystems just work is antiquated. This was on a brand new 16T drive, so I didn't think that it was worth the month that it would take to run the badblocks program which doesn't really scale to modern disk sizes. Besides, SMART said that it was fine. Although it's been discredited by some, I'm still a believer in "stop and fsck" policing of disk drives. Unmounted the filesystem and ran fsck to discover that btrfs had to do its own thing. No idea why; I guess some think that incompatibility is a good thing. Ran "btrfs check" which reported errors in the filesystem but was otherwise useless BECAUSE IT DIDN'T FIX ANYTHING. What good is knowing that the filesystem has errors if you can't fix them? Near the top of the manual page it says: Warning Do not use --repair unless you are advised to do so by a developer or an experienced user, and then only after having accepted that no fsck successfully repair all types of filesystem corruption. Eg. some other software or hardware bugs can fatally damage a volume. Whoa! I'm sure that operators are standing by, call 1-800-FIX-BTRFS. Really? Is a ploy by the developers to form a support business? Later on, the manual page says: DANGEROUS OPTIONS --repair enable the repair mode and attempt to fix problems where possible Note there’s a warning and 10 second delay when this option is run without --force to give users a chance to think twice before running repair, the warnings in documentation have shown to be insufficient Since when is it dangerous to repair a filesystem? That's a new one to me. Having no option other than not being able to use the disk, I ran btrfs check with the --repair option. It crashed. Lesson so far is that trusting my data to an unreliable unrepairable filesystem is not a good idea. Since this was one of my media disks I just rebuilt it using ext4. Last week I was working away and tried to write out a file to discover that /home and /root had become read-only. Charming. Tried rebooting, but couldn't since btrfs filesystems aren't checked and repaired. Plugged in a flash drive with a live version, managed to successfully run --repair, and rebooted. Lasted about 15 minutes before flipping back to read only with the same error. Time to suck it up and revert. Started a clean reinstall. Got stuck because it crashed during disk setup with anaconda giving me a completely useless big python stack trace. Eventually figured out that it was unable to delete the btrfs filesystem that had errors so it just crashed instead. Wiped it using dd; nice that some reliable tools still survive. Finished the installation and am back up and running. Any of the rest of you have any experiences with btrfs? I'm sure that it works fine at large companies that can afford a team of disk babysitters. What benefits does btrfs provide that other filesystem formats such as ext4 and ZFS don't? Is it just a continuation of the "we have to do everything ourselves and under no circumstances use anything that came from the BSD world" mentality? So what's the future for filesystem repair? Does it look like the past? Is Ken's original need for dsw going to rise from the dead? In my limited experience btrfs is a BiTteR FileSystem to swallow. Or, as Saturday Night Live might put it: And now, linux, starring the not ready for prime time filesystem. Seems like something that's been under development for around 15 years should be in better shape. Jon

3 years, 10 months

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Who said ...

by arnold＠skeeve.com

... DEC Diagnositcs would run on a beached whale ? Anyone remember and/or know? (It seems to apply to other manufacturer's diagnostics as well, even today.) Thanks, Arnold

3 years, 10 months

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A language question

by Richard Salz

I hope that this does not start any kind of language flaming and that if something starts the moderator will shut it down quickly. Where did the name for abort(3) and SIGABRT come from? I believe it was derived from the IBM term ABEND, but would like to know one way or the other.

3 years, 10 months

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Re: [TUHS] Who said ...

by norman＠oclsc.org

Clem Cole: I believe the line was: *"running **DEC Diagnostics is like kicking a dead whale down the beach.*" As for who said it, I'm not sure, but I think it was someone like Rob Kolstad or Henry Spencer. ===== The nearest I can remember encountering before was a somewhat different quote, attributed to Steve Johnson: Running TSO is like kicking a dead whale down the beach. Since scj is on this list, maybe he can confirm that part. I don't remember hearing it applied to diagnostics. I can imagine someone saying it, because DEC's hardware diags were written by hardware people, not software people; they required a somewhat arcane configuration language, one that made more sense if you understood how the different pieces of hardware connected together. I learned to work with it and found it no less usable than, say, the clunky verbose command languages of DEC's operating systems; but I have always preferred to think in low levels. DEC's diags were far from perfect, but they were a hell of a lot better than the largely-nonexistent diags available for modern Intel-architecture systems. I am right now dealing with a system that has an intermittent fault, that causes the OS to crash in the middle of some device driver every so often. Other identical systems don't, so I don't think it's software. Were it a PDP-11 or a VAX I'd fire up the diagnostics for a while, and have at least a chance of spotting the problem; today, memtest is about the only such option, and a solid week of running memtest didn't shake out anything (reasonably enough, who says it's a memory problem?). Give me XXDP, not just the Blue Screen of Death. Norman Wilson Toronto ON

3 years, 10 months

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Re: [TUHS] Is it time to resurrect the original dsw (delete with switches)?

by norman＠oclsc.org

Not to get into what is soemthing of a religious war, but this was the paper that convinced me that silent data corruption in storage is worth thinking about: http://www.cs.toronto.edu/~bianca/papers/fast08.pdf A key point is that the character of the errors they found suggests it's not just the disks one ought to worry about, but all the hardware and software (much of the latter inside disks and storage controllers and the like) in the storage stack. I had heard anecdotes long before (e.g. from Andrew Hume) suggesting silent data corruption had become prominent enough to matter, but this paper was the first real study I came across. I have used ZFS for my home file server for more than a decade; presently on an antique version of Solaris, but I hope to migrate to OpenZFS on a newer OS and hardware. So far as I can tell ZFS in old Solaris is quite stable and reliable. As Ted has said, there are philosophical reasons why some prefer to avoid it, but if you don't subscribe to those it's a fine answer. I've been hearing anecdotes since forever about sharp edges lurking here and there in BtrFS. It does seem to be eternally unready for production use if you really care about your data. It's all anecdotes so I don't know how seriously to take it, but since I'm comfortable with ZFS I don't worry about it. Norman Wilson Toronto ON PS: Disclosure: I work in the same (large) CS department as Bianca Schroeder, and admire her work in general, though the paper cited above was my first taste of it.

3 years, 10 months

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Re: [TUHS] Can't break line warning

by Douglas McIlroy

This may be due to logic similar to that of a classic feature that I always deemed a bug: troff begins a new page when the current page is exactly filled, rather than waiting until forced by content that doesn't fit. If this condition happens at the end of a document, a spurious blank page results. Worse, if the page header happens to change just after the exactly filled page, the old heading will be produced before the new heading is read. Doug

3 years, 10 months

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Systematic approach to command-line interfaces

by Douglas McIlroy

> fork() is a great model for a single-threaded text processing pipeline to do > automated typesetting. (More generally, anything that is a straightforward > composition of filter/transform stages.) Which is, y'know, what Unix is *for*. > It's not so great for a responsive GUI in front of a multi-function interactive program. "Single-threaded" is not a term I would apply to multiple processes in a pipeline. If you mean a single track of data flow, fine, but the fact that that's a prevalent configuration of cooperating processes in Unix is an artifact of shell syntax, not an inherent property of pipe-style IPC. The cooperating processes in Rob Pike's 20th century window systems and screen editors, for example, worked smoothly without interrupts or events - only stream connections. I see no abstract distinction between these programs and "stuff people play with on their phones." It bears repeating, too, that stream connections are much easier to reason about than asynchronous communication. Thus code built on streams is far less vulnerable to timing bugs. At last a prince has come to awaken the sleeping beauty of stream connections. In Go (Pike again) we have a widely accepted programming language that can fully exploit them, "[w]hich is, y'know, what Unix is 'for'." (If you wish, you may read "process" above to include threads, but I'll stay out of that.) Doug

3 years, 11 months

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Who is that in the framed photograph near the ceiling?

by norman＠oclsc.org

Steve Simon: once again i am taken aback at the good taste of the residents of the unix room. As a whilom denizen of that esteemed playroom, I question both the accuracy and the relevance of that metric. Besides, what happened to the sheep shelf? Was it scrubbed away after I left? And, Ken, whatever happened to Dolly the Sheep (after she was hidden to avoid upsetting visitors)? Norman Wilson Toronto ON No longer a subscriber to sheep! magazine

3 years, 11 months

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Who is that in the framed photograph near the ceiling?

by Steve Simon

great picture. once again i am taken aback at the good taste of the residents of the unix room. -Steve

3 years, 11 months

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Who is that in the framed photograph near the ceiling?

by William Cheswick

> I don't think anyone knows. Nobody relevant, I believe. > > -rob I understand that Dave Presotto bought that photo at a garage sale for $1. The photo hung in the Unix Room for years, at one point labeled “Peter Weinberger.” One day I removed it from its careful mounting and scanned in the photo. It bore the label “what, no steak?” The photo was stolen from a wall sometime after I left. The scanned image is at https://cheswick.com/ches/tmp/whatnosteak.jpeg ches

3 years, 11 months

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