From tuhs at tuhs.org Wed Oct 1 01:22:18 2025 From: tuhs at tuhs.org (Lars Brinkhoff via TUHS) Date: Tue, 30 Sep 2025 15:22:18 +0000 Subject: [TUHS] Interesting MIT links In-Reply-To: <735ea170-d408-73e5-9307-067e5d4ed53b@bitsavers.org> (Al Kossow via TUHS's message of "Mon, 29 Sep 2025 11:19:59 -0700") References: <7wikh15g5b.fsf@junk.nocrew.org> <735ea170-d408-73e5-9307-067e5d4ed53b@bitsavers.org> Message-ID: <7w7bxg3qz9.fsf@junk.nocrew.org> Al Kossow wrote: > Did all the file recovery documents (like the system names) make it > into what the MIT Archives have, or just the tape images? I didn't seem. Often I had to infer which system a tape came from from its contents. Some tapes have photos of the label. > There are problems with the images as well, like John Bordynuik > inventing his own .tap format with bad blocks handled differently, all > undocumented... I have seen many variants in there, such as little or big endian record size, records padded to 16 bits or not. Some records have frames dropped from the beginning or the end. Also old ITS backup tapes were transferred from low density tapes to a fewer number of high density tapes in the 80s, so sometimes same file appear in multiple savesets on a single tape. From tuhs at tuhs.org Wed Oct 1 01:29:48 2025 From: tuhs at tuhs.org (Lars Brinkhoff via TUHS) Date: Tue, 30 Sep 2025 15:29:48 +0000 Subject: [TUHS] Interesting MIT links In-Reply-To: (Rich Salz via TUHS's message of "Mon, 29 Sep 2025 11:57:06 -0400") References: Message-ID: <7w34843qmr.fsf@junk.nocrew.org> Rich Salz wrote: > There *must* be Unix stuff in the MIT collection. One unusual thing I found was a copy of Harris HCX/UX. It's their Unix port for the "Tahoe" architecture; you know as in 4.3BSD-Tahoe. I don't know what to do about this. From tuhs at tuhs.org Wed Oct 1 08:55:14 2025 From: tuhs at tuhs.org (jslee via TUHS) Date: Wed, 01 Oct 2025 08:55:14 +1000 Subject: [TUHS] Interesting MIT links In-Reply-To: <7w34843qmr.fsf@junk.nocrew.org> References: <7w34843qmr.fsf@junk.nocrew.org> Message-ID: <5a5b2deb-bf64-4695-bd55-f7cc88ebf17b@app.fastmail.com> Hi, On Wed, 1 Oct 2025, at 01:29, Lars Brinkhoff via TUHS wrote: > Rich Salz wrote: >> There *must* be Unix stuff in the MIT collection. > > One unusual thing I found was a copy of Harris HCX/UX. I had never heard of the Harris before today. I’d heard of BSD Tahoe (I think Rich Stevens may have mentioned it in one of his books? Or maybe I just saw it in a family tree…) but not the machine Anyway mainly posting as after some googling I found this blogue poste: https://virtuallyfun.com/2017/02/24/the-harris-hcx-9-aka-tahoe-platform/ One commenter mentions that Dayton University also had one of these machines. John From tuhs at tuhs.org Fri Oct 3 11:33:25 2025 From: tuhs at tuhs.org (christopher fujino via TUHS) Date: Thu, 2 Oct 2025 18:33:25 -0700 Subject: [TUHS] The origins of portability in C Message-ID: I have often read things like, "`int`s in C are of unfixed size so that Unix could be ported." So I was surprised to read in Dennis Ritchie's "The Development of the C Language" that: PL/I, the implementation language of Multics, was not much to our > tastes, but we were also using other languages, including BCPL, and we > regretted losing the > advantages of writing programs in a language above the level of assembler, > such as ease of writ- > ing and clarity of understanding. At the time we did not put much weight > on portability; interest > in this arose later. > Brian Kernighan quotes Steve Johnson in "Unix: A History and a Memoir": There was another pressure to make Unix portable. A number of DEC's > competitors were beginning to grumble that regulated AT&T had too cozy a > relationship with DEC. We pointed out that there were no other machines > like the PDP-11 on the market, but this argument was getting weaker. > Dennis hooked me into the portability effort with one sentence: 'I think > that it would be easier to move Unix to another piece of hardware than to > rewrite an application to run under a different operating system.' I was > all in from that point on. A few questions: 1. Was Johnson's Portable C Compiler developed explicitly to port Unix, or was it already around? 2. And if it was already around, what was the initial motivation for creating a portable C compiler? 3. Am I right to assume that prior to the Portable C Compiler, C's primitives were thought of as PDP-11 specific? Thanks! Chris From tuhs at tuhs.org Fri Oct 3 11:52:00 2025 From: tuhs at tuhs.org (Rob Pike via TUHS) Date: Fri, 3 Oct 2025 11:52:00 +1000 Subject: [TUHS] The origins of portability in C In-Reply-To: References: Message-ID: It was done for the port to the Interdata. To answer question 3, I often heard (and early on, believed) that things like *p++ were invented for the addressing modes on the PDP-11, but was told by Ken and Dennis that they were not original. -rob On Fri, Oct 3, 2025 at 11:34 AM christopher fujino via TUHS wrote: > I have often read things like, "`int`s in C are of unfixed size so that > Unix could be ported." So I was surprised to read in Dennis Ritchie's "The > Development of the C Language" that: > > PL/I, the implementation language of Multics, was not much to our > > tastes, but we were also using other languages, including BCPL, and we > > regretted losing the > > advantages of writing programs in a language above the level of > assembler, > > such as ease of writ- > > ing and clarity of understanding. At the time we did not put much weight > > on portability; interest > > in this arose later. > > > > Brian Kernighan quotes Steve Johnson in "Unix: A History and a Memoir": > > There was another pressure to make Unix portable. A number of DEC's > > competitors were beginning to grumble that regulated AT&T had too cozy a > > relationship with DEC. We pointed out that there were no other machines > > like the PDP-11 on the market, but this argument was getting weaker. > > Dennis hooked me into the portability effort with one sentence: 'I think > > that it would be easier to move Unix to another piece of hardware than to > > rewrite an application to run under a different operating system.' I was > > all in from that point on. > > > A few questions: > > 1. Was Johnson's Portable C Compiler developed explicitly to port Unix, or > was it already around? > 2. And if it was already around, what was the initial motivation for > creating a portable C compiler? > 3. Am I right to assume that prior to the Portable C Compiler, C's > primitives were thought of as PDP-11 specific? > > Thanks! > > Chris > From tuhs at tuhs.org Fri Oct 3 13:02:47 2025 From: tuhs at tuhs.org (Dave Horsfall via TUHS) Date: Fri, 3 Oct 2025 13:02:47 +1000 (EST) Subject: [TUHS] The origins of portability in C In-Reply-To: References: Message-ID: On Fri, 3 Oct 2025, Rob Pike via TUHS wrote: > It was done for the port to the Interdata. To answer question 3, I often > heard (and early on, believed) that things like *p++ were invented for > the addressing modes on the PDP-11, but was told by Ken and Dennis that > they were not original. I believe the same thing was said about the SOB instruction too. -- Dave From tuhs at tuhs.org Fri Oct 3 14:30:53 2025 From: tuhs at tuhs.org (ron minnich via TUHS) Date: Thu, 2 Oct 2025 21:30:53 -0700 Subject: [TUHS] The origins of portability in C In-Reply-To: References: Message-ID: if an instruction named SOB had not existed, it would have been necessary to create one. On Thu, Oct 2, 2025 at 8:14 PM Dave Horsfall via TUHS wrote: > On Fri, 3 Oct 2025, Rob Pike via TUHS wrote: > > > It was done for the port to the Interdata. To answer question 3, I often > > heard (and early on, believed) that things like *p++ were invented for > > the addressing modes on the PDP-11, but was told by Ken and Dennis that > > they were not original. > > I believe the same thing was said about the SOB instruction too. > > -- Dave > From tuhs at tuhs.org Sat Oct 4 00:12:01 2025 From: tuhs at tuhs.org (Douglas McIlroy via TUHS) Date: Fri, 3 Oct 2025 10:12:01 -0400 Subject: [TUHS] The origins of portability in C External Inbox Forums Message-ID: Portability of Fortran code was a major theme at Bell Labs. Phyllis Fox oversaw the creation of the Port library of numerical software, which became publicly available upon the advent of the internet. Before the Port library, Stan Brown, Barbara Rider, and Andy Hall had been central to an ambitious portability effort for Altran, a symbolic-algebra language. They identified Pfort, a subset of Fortran that was portable except for issues of data representation. In particular, Altran implemented multiple-precision integers. A verifier to assure that Fortran code complied with Pfort was written in Pfort. The M6 macroprocessor, also written in Pfort, was created to deal with adjusting Fortran code that depended on word size or character code. The Altran compiler itself was written in Pfort tailored by a set of M6 definitions for each machine architecture. Of course making C portable was a bigger deal than doing it for Altran. C had to compile to different instruction sets, while Altran always compiled to Pfort. But the Altran portability effort certainly fed into the C project, particularly via Steve Johnson, who worked on both. One notable congruence is their use of macro preprocessors. Doug From tuhs at tuhs.org Sun Oct 5 06:38:00 2025 From: tuhs at tuhs.org (David Barto via TUHS) Date: Sat, 4 Oct 2025 13:38:00 -0700 Subject: [TUHS] inode - does it have a meaning? Message-ID: <143E170E-F64F-4AEE-83B1-BAB134267099@kdbarto.org> In a blog post today I read: In most modern file systems, those data structures are known as inodes, and their numbers are inode numbers, sometimes shortened to inodes. The term is thought to be a contraction of index node, which certainly makes sense, but is lost in the mists of time. This was written by a fellow who is reasonably smart and knows his way around things MacOS, though not things UNIX. So before I go and tell him that inode really does mean ‘index node’, I’m checking here to clear the “mists of time.” I’ve always understood it to be a shortening of ‘index node’. Wikipedia (https://en.wikipedia.org/wiki/Inode) says There has been uncertainty on the Linux kernel mailing list about the reason for the "i" in "inode". In 2002, the question was brought to Unix pioneer Dennis Ritchie, who replied:[4] In truth, I don't know either. It was just a term that we started to use. "Index" is my best guess, because of the slightly unusual file system structure that stored the access information of files as a flat array on the disk, with all the hierarchical directory information living aside from this. Thus the i-number is an index in this array, the i-node is the selected element of the array. (The "i-" notation was used in the 1st edition manual; its hyphen was gradually dropped.) Further the Wikipedia article states that Bach says that the word ‘inode’ is a contraction of the term index node. So is there a ‘definitive’ answer for this, or is it really lost in the mists of time? David Men always learn from their mistakes how to make new ones. A.J.P. Taylor David Barto barto at kdbarto.org From tuhs at tuhs.org Sun Oct 5 07:15:28 2025 From: tuhs at tuhs.org (Jim Mellander via TUHS) Date: Sat, 4 Oct 2025 14:15:28 -0700 Subject: [TUHS] PDP-11/70 in Cory Hall, Berkeley '74 or 75 Message-ID: Hi all: I had the occasion to use the PDP-11/70 on the ground floor of Cory Hall. I was not a student, but was in the Navy stationed at Treasure Island, but groked Unix & visited there on my time off to tinker, among other things. I always have wondered who were the long hairs who were working inside the glass partition on the system. Also, I played with a PDP-11/45 in Evans Hall. I'm interested in any information anyone has about those times and places. Thanks in advance, Jim Mellander From tuhs at tuhs.org Sun Oct 5 07:57:15 2025 From: tuhs at tuhs.org (steve jenkin via TUHS) Date: Sun, 5 Oct 2025 08:57:15 +1100 Subject: [TUHS] inode - does it have a meaning? In-Reply-To: <143E170E-F64F-4AEE-83B1-BAB134267099@kdbarto.org> References: <143E170E-F64F-4AEE-83B1-BAB134267099@kdbarto.org> Message-ID: <0BD89802-685A-4416-9527-5CF39F0274B6@canb.auug.org.au> In 1989, Ken was interviewed by Mike Mahoney of Princeton, as part of the “Unix Oral History Project”. It seems ‘inode’ was being used from 1969 when Ken & Dennis were doing design, with Rudd Canaday in his office. ====================== Princeton have removed the original site. Copes can be found at: An edited summary by Mahoney: ====================== Ken’s Interview of "9-6-89" Thompson: Yeah. I was doing it on the 635 at the time. Yeah . I got these exponential curves where before it would get into trouble it would go way out and get lots and lots of simultaneous accesses going… I was playing with a disk sorting algorithms and caching algorithms at the time. All of those actually went into UNIX. Um. MSM: This would be the research aspect of the work? Thompson: Yeah. Then in the actual design. At that point, it just went to… There was a model of a user and a model of this, and they generated activities, and the activity went into the disks that were sorted and things like that. Um, um. It was never down to a design to the point of where you put the addresses, how you expand files and things like that. It was never down to that level. It was always at some higher level. I think it was just like one or two meetings, Dennis and Canaday and myself. Was just discussing these ideas of the general nature of keeping the files out of each other's hair and the nitty-gritty of expanding. Of the real implementation, where you put the block addresses, where you put this and this. I remember, um, we did it in Canaday's office. At the end of this discussion Canaday picked up the phone, and there was a new service in Bell Laboratories, dictation, where you call up essentially a tape recorder and you give notes, and then the next morning notes are typed and sent to you. The next day, these notes came back and the acronyms were butchered, like "inode" was "eyen" (Laughing). ====================== > On 5 Oct 2025, at 07:38, David Barto via TUHS wrote: > > In a blog post today I read: > > In most modern file systems, those data structures are > known as inodes, and their numbers are inode numbers, > sometimes shortened to inodes. The term is thought > to be a contraction of index node, which certainly > makes sense, but is lost in the mists of time. > > This was written by a fellow who is reasonably smart and knows > his way around things MacOS, though not things UNIX. So before > I go and tell him that inode really does mean ‘index node’, I’m > checking here to clear the “mists of time.” > > I’ve always understood it to be a shortening of ‘index node’. > > Wikipedia (https://en.wikipedia.org/wiki/Inode) says > > There has been uncertainty on the Linux kernel mailing list > about the reason for the "i" in "inode". In 2002, the question > was brought to Unix pioneer Dennis Ritchie, who replied:[4] > > In truth, I don't know either. It was just a term that we > started to use. "Index" is my best guess, because of the > slightly unusual file system structure that stored the > access information of files as a flat array on the disk, > with all the hierarchical directory information living > aside from this. Thus the i-number is an index in this array, > the i-node is the selected element of the array. > (The "i-" notation was used in the 1st edition manual; > its hyphen was gradually dropped.) > > Further the Wikipedia article states that Bach says that the word ‘inode’ > is a contraction of the term index node. > > So is there a ‘definitive’ answer for this, or is it really lost in > the mists of time? > > David > > Men always learn from their mistakes how to make new ones. > A.J.P. Taylor > > David Barto > barto at kdbarto.org > > > -- Steve Jenkin, IT Systems and Design 0412 786 915 (+61 412 786 915) PO Box 38, Kippax ACT 2615, AUSTRALIA mailto:sjenkin at canb.auug.org.au http://members.tip.net.au/~sjenkin From tuhs at tuhs.org Sun Oct 5 08:54:30 2025 From: tuhs at tuhs.org (Steffen Nurpmeso via TUHS) Date: Sun, 05 Oct 2025 00:54:30 +0200 Subject: [TUHS] inode - does it have a meaning? In-Reply-To: <143E170E-F64F-4AEE-83B1-BAB134267099@kdbarto.org> References: <143E170E-F64F-4AEE-83B1-BAB134267099@kdbarto.org> Message-ID: <20251004225430.mp_rFBJr@steffen%sdaoden.eu> David Barto via TUHS wrote in <143E170E-F64F-4AEE-83B1-BAB134267099 at kdbarto.org>: |In a blog post today I read: | | In most modern file systems, those data structures are | known as inodes, and their numbers are inode numbers, | sometimes shortened to inodes. The term is thought | to be a contraction of index node, which certainly | makes sense, but is lost in the mists of time. | |This was written by a fellow who is reasonably smart and knows |his way around things MacOS, though not things UNIX. So before |I go and tell him that inode really does mean ‘index node’, I’m |checking here to clear the “mists of time.” | |I’ve always understood it to be a shortening of ‘index node’. | |Wikipedia (https://en.wikipedia.org/wiki/Inode) says | | There has been uncertainty on the Linux kernel mailing list | about the reason for the "i" in "inode". In 2002, the question | was brought to Unix pioneer Dennis Ritchie, who replied:[4] | | In truth, I don't know either. It was just a term that we | started to use. "Index" is my best guess, because of the | slightly unusual file system structure that stored the | access information of files as a flat array on the disk, | with all the hierarchical directory information living | aside from this. Thus the i-number is an index in this array, | the i-node is the selected element of the array. | (The "i-" notation was used in the 1st edition manual; | its hyphen was gradually dropped.) | |Further the Wikipedia article states that Bach says that the word ‘inode’ |is a contraction of the term index node. | |So is there a ‘definitive’ answer for this, or is it really lost in |the mists of time? Sure is to me only that in 4.2BSD the "A Fast File System for UNIX" paper (share/doc/smm/05.fastfs/) talks +Every file has a descriptor associated with it called an +.I "inode". +The inode contains information describing ownership of the file, +time stamps marking last modification and access times for the file, +and an array of indices that point to the data blocks for the file. +For the purposes of this section, we assume that the first 8 blocks +of the file are directly referenced by values stored +in the inode structure itself*. Node with array of indices. Isn't this an influential paper? Not mentioned in Wikipedia. --steffen | |Der Kragenbaer, The moon bear, |der holt sich munter he cheerfully and one by one |einen nach dem anderen runter wa.ks himself off |(By Robert Gernhardt) From tuhs at tuhs.org Sun Oct 5 09:04:47 2025 From: tuhs at tuhs.org (Jon Forrest via TUHS) Date: Sat, 4 Oct 2025 16:04:47 -0700 Subject: [TUHS] inode - does it have a meaning? In-Reply-To: <143E170E-F64F-4AEE-83B1-BAB134267099@kdbarto.org> References: <143E170E-F64F-4AEE-83B1-BAB134267099@kdbarto.org> Message-ID: On 10/4/25 1:38 PM, David Barto via TUHS wrote: > In a blog post today I read: > > In most modern file systems, those data structures are > known as inodes, and their numbers are inode numbers, > sometimes shortened to inodes. The term is thought > to be a contraction of index node, which certainly > makes sense, but is lost in the mists of time. The "provably secure" version of Unix, called KSOS, used "jnodes" instead of "inodes". I think this was because the main architect of KSOS was Jay McCauley, and he named them after himself. Jon From tuhs at tuhs.org Sun Oct 5 09:16:32 2025 From: tuhs at tuhs.org (Noel Chiappa via TUHS) Date: Sat, 4 Oct 2025 19:16:32 -0400 (EDT) Subject: [TUHS] inode - does it have a meaning? Message-ID: <20251004231632.77B4418C077@mercury.lcs.mit.edu> > From: Steffen Nurpmeso > Isn't this an influential paper. Written well over a decade after initial UNIX. The chances that anyone there knew anything about very early UNIX (especially as old documents had not yet started to show up on the early Internet, back then) are zero. Noel From tuhs at tuhs.org Sun Oct 5 09:24:01 2025 From: tuhs at tuhs.org (Warner Losh via TUHS) Date: Sat, 4 Oct 2025 17:24:01 -0600 Subject: [TUHS] inode - does it have a meaning? In-Reply-To: <20251004231632.77B4418C077@mercury.lcs.mit.edu> References: <20251004231632.77B4418C077@mercury.lcs.mit.edu> Message-ID: On Sat, Oct 4, 2025 at 5:16 PM Noel Chiappa via TUHS wrote: > > From: Steffen Nurpmeso > > > Isn't this an influential paper. > > Written well over a decade after initial UNIX. The chances that anyone > there > knew anything about very early UNIX (especially as old documents had not > yet > started to show up on the early Internet, back then) are zero. > Yet they could have had it from oral history, given Ken's 1975 sabbatical to Berkeley, no? And the paper pre-dates his later recollections, and surely he reviewed it and would have raised an objection if he knew it was wrong. Kirk McKusick, the author, is on this list, I think. Though, I will grant it's not primary evidence. Warner From tuhs at tuhs.org Sun Oct 5 14:57:03 2025 From: tuhs at tuhs.org (Warren Toomey via TUHS) Date: Sun, 5 Oct 2025 14:57:03 +1000 Subject: [TUHS] inode - does it have a meaning? In-Reply-To: <143E170E-F64F-4AEE-83B1-BAB134267099@kdbarto.org> References: <143E170E-F64F-4AEE-83B1-BAB134267099@kdbarto.org> Message-ID: On Sat, Oct 04, 2025 at 01:38:00PM -0700, David Barto via TUHS wrote: > In a blog post today I read: > > In most modern file systems, those data structures are > known as inodes, and their numbers are inode numbers, > sometimes shortened to inodes. The term is thought > to be a contraction of index node, which certainly > makes sense, but is lost in the mists of time. This is in the 197 CACM paper: A directory entry contains only a name for the associated file and a pointer to the file itself. This pointer is an integer called the i-number (for index number) of the file. When the file is accessed, its i-number is used as an index into a system table (the i-list) stored in a known part of the device on which the directory resides. The entry thereby found (the file’s i-node) contains the description of the file ... But an earlier version of the paper has this: A directory entry contains only a name for the associated file and a pointer to the file itself. This pointer is an integer called the i-number (for identification number) of the file. See https://github.com/DoctorWkt/unix_timesharing_paper/blob/master/filesystem.md So you could argue that, at the time of this draft, the wording implies "identification node" for i-node. Cheers, Warren