TUHS

tuhs@tuhs.org

6532 discussions

Joe Condon [ long, slightly off-topic post ]

by Jon Steinhart

So as part of my attempt to remember the names of the folks with who I worked I just read Joe's wikipedia page which doesn't seem accurate to me. If this is too off topic let me know. The page says that Joe "was exposed to UNIX on the Honeywell 516 machines in the early 1970s." This seems wrong to me. We did have a 516, but it ran an experimental virtual memory system called 516-TSS. I lived on this system and still have some of the octal instruction opcodes burned into my brain-ROM. I seem to recall that the department got a PDP-11/40 that ran UNIX version 3 in maybe the summer of 1972 which I used for writing up the documentation for my project. The page also says that "Condon and Ken Thompson promoted the use of the C programming language for AT&T’s switching system control programs. Condon acquired a small AT&T PBX (telephone switch) that handled about 50 phones; he made the necessary hardware changes and Thompson wrote the necessary software programs. The PBX code rewrite in C was a success and hastened the adoption of C for all switching system software within AT&T." This also doesn't match my recollection. One of the big projects in the department was what I think was called SS1 for Slave Switch 1, which was an all-digital telephone exchange. It replaced some other monstrosity whose details I can't recall except that Joe and Dave Weller signed the appropriate paperwork allowing me to take a good portion of it home when it was decommissioned giving me a huge stock of Augat wirewrap boards and 7400-series parts. The SS1 was originally going to use LSI-11s but the stupid way in which DEC implemented the DRAM refresh made that impossible. I think that the final thing used a couple of PDP-10s. As part of being all-digital it used the digital filter work by Jim Kaiser and Hal Alles. I do remember going into Carl Christensen's office to ask him a question and found him staring at a huge C listing; it turns out that a bug in the code had caused SS1 to send KP pulses without their corresponding ST pulses with the result that every single keypulse sender in the Berkeley Heights telephone exchange was taken off line and needed to be manually reset to restore long distance service. They were not happy. Anyway, unless there was something that happened later after I was gone, I'm thinking that the wikipedia page is incorrect and that this PBX was built, not acquired. It was, as far as I know, the first use of C to control machinery. It's actually because of this machine that I'm trying to track down the name of some folks from down at the end of the hall. I have strong memories of the Bell System exhibit at the '64 World's Fair, especially the booth where one could go and talk and they had bar graphs on a monitor showing the spectrum of your speech and could mess with it. Many years later, while waiting for some deck of cards to finish loading, I poked my head into the lab down the hall to see what they were doing in there, and noticed polaroid photos of that exhibit featuring the guys in the lab. Once they stopped telling stories from the World's Fair, they taught me a lesson about systems engineering that opened my eyes. They were developing a circuit that replaced the pound of iron hybrid transformers that were on every telephone line with a small toroid and an op-amp. Their circuit would sense when the iron was getting close to saturation and run current through an additional winding to keep it in the linear region. While that circuit cost a lot more than a hybrid transformer, it paid for itself by reducing the amount of concrete needed to build telephone exchanges. Would love to know who these guys were which is why an org chart would help. And maybe someone out there like Ken can help me out with the accurate history. Jon

6 years, 2 months

Re: [TUHS] 516-TSS, was re: Joe Condon

by jnc＠mercury.lcs.mit.edu

> From: Grant Taylor > What OS did the 516 / TIP run? Google is your friend. A Web search for 'ARPANET IMP software' will answer your question. Noel

6 years, 2 months

Re: [TUHS] UNIX System Internals

by jnc＠mercury.lcs.mit.edu

> From: Jon Steinhart > OK, well, how do we make this happen? Is it bound or un-bound, and if the former, are you OK with unbinding it? If the former, and 'no', we either need to rope in someone with one of those special rigs for scanning books, or do it by hand. If not, I have an auto-feed scanner, and volunteer to do it. How large are the pages? Noel

6 years, 2 months

UNIX System Internals

by Jon Steinhart

Don't know if this is of interest to anybody out there, but I was just looking for something else in the basement and came across two notebooks that look like a UNIX System Internals course. Appears to cover version 6, version 7, PWB, 32V, System III, and System V. Has the Western Electric seal of disapproval on the front. Jon

6 years, 2 months

UNIX System Internals

by Norman Wilson

I'd love to see this stuff. Were I not so far away I'd offer to scan them for you, but it shouldn't be hard to find someone who can in the Bay Area. (Attention USENIX Association, I approve use of my membership dues to support this!) Norman Wilson Toronto ON

6 years, 2 months

looking for HOSTS.TXT parsers and how is /dev/net/HOSTNAME enabled?

by reed＠reedmedia.net

This email is two parts. I am researching 1970's symbolic name to network address mapping routines. 1) I am looking for parsers for ancient (pre mid 1982) HOSTS.TXT. Since this is Unix list, for Unix is fine :) RFC 597 (12 December 1973) says a hostname list will be maintained at the NIC with the location to be announced. (Interestingly NIC as in FEINLER@NIC is probably a nickname as it is not listed in the host status list. I am guessing it is a nickname for SRI-ARC or OFFICE-1.) RFC 606 (December 1973) says there are different hosts lists, but "now" there is "the official list of host names". It proposed that it should be maintained online in machine-readable form. It proposes a format and suggested attributes. RFC 607 (January 10, 1974) the NIC agrees that NIC maintain a text file of hostnames, addresses, and attributes. (It has also been suggested separately.) The source is maintained in NLS format with multiple attributes. (What is this NLS format?) A program could be written to generate a weekly ASCII file. They will write the program and the generated file will be at OFFICE-1 (IMP #43?) with pathname of <NETINFO>HOSTS.TXT (It's not Unix. It's TENEX I think. The ">" is the directory delimiter, but what is "<"?) I have found a few copies of a hostname table, like https://emaillab.jp/pub/hosts/1974/host_names_1974.pdf and https://www.bortzmeyer.org/files/hosts.txt-1982-1.pdf But these don't appear to be the machine parseable files as defined in the RFC 608 format. These are just printed formats. (I have also found many of the host status reports.) Well I cannot find a copy of the HOSTS.TXT file anywhere. I am not looking for the RFC 810 (1 March 1982) or later format (which is easily found). http://pdp-10.trailing-edge.com/SRI_NIC_PERM_SRC_3_19910112/01/utility/ps-p… may have copies of it (old format is OHOSTS.TXT). But I cannot figure out if or where there are individual file downloads there. Any ideas?) That leads me to my question ... does anyone know where parser code for the HOSTS.TXT file is at? 2) I skimmed through some C code (for Unix) for sendmsg, mmdf, srvrftp, mailer.c, telnet.c that use /dev/net/ followed by up to 14-character hostname. I am trying to find the kernel code or routines that enable device driver named with a hostname. Any ideas? (In particular I'd like to know how those names map to a remote host's address.) I am researching 1970's symbolic name to network address mapping routines, but the only ones I have found are primitive: Purdue's "modest UNIX network" using mx and Berkeley's Berknet (single letter hostnames). But both use simple compiled-in name-to-address tables. (The Purdue implementation looks interesting as it has some design to connect between IMPs too, but I don't see any code for finding IMP numbers via names. By the way, their "csh" tool was their "connected shell" to run a shell on a remote host. The manual had the list of hostnames in it. See the Purdue usenix tape.) Thanks, Jeremy C. Reed echo 'EhZ[h ^jjf0%%h[[Zc[Z_W$d[j%Xeeai%ZW[ced#]dk#f[d]k_d%' | \ tr '#-~' '\-.-{'

6 years, 2 months

Paper discussing Unix boot process?

by Pat Barron

Long ago, I could swear I'd read a paper (or a TM, or something) that described the process of a Unix system booting. It presented a timeline describing the sequence of how the boot blocks are loaded, the kernel is loaded, MMU turned on, etc. However, other than that, I can't recall a thing about it - can't remember the title, the author, or where I found it. I don't remember if it talked about this process on a Bell Labs Unix system, or a BSD system (though it had to be one of those - either 7th Edition or BSD). The timeframe was probably mid to late 1980's, though I could be wrong about that. Does this ring a bell with anyone? I really wish I could find it again... --Pat.

6 years, 2 months

Talk about some interesting things about Dennis

by Norman Wilson

What is Dennis's character? Is he very humorous? Thank you. He was more humorous when he was still alive, but I think he would have appreciated this joke. Norman Wilson Toronto ON

6 years, 2 months

Talk about some interesting things about Dennis

by Caipenghui

Hello, everyone! Can you share some interesting things around Dennis? What is Dennis's character? Is he very humorous? Thank you. Caipenghui

6 years, 2 months

Re: [TUHS] Paper discussing Unix boot process?

by Paul Ruizendaal

Maybe xv6 has an explanation of the boot process that is of use to the original poster: https://pdos.csail.mit.edu/6.828/2018/xv6.html Paul

6 years, 2 months

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

1996

1995

1994

1993

1992

1991

1990

TUHS