Paul - you made a couple of comments and asked a few questions which I'll take a shot at best I can having been there. Sam spent a few hours in my apartment drinking beer and watching football, and sometimes doing laundry much less and arguing networking stuff. (I had a washer and dryer in those days and he had a vacuum cleaner which I borrowed from him). Before CSRG, Sam had been working for a networking start up in the lower bay who's name escapes me at the moment. IIRC they had been doing a terminal concentrator of some type. Previous to UCB, I had been at Tek. Presotto at DEC, Baden and George at Pr1me on the their 750. Sundays were often a football and beer session, usually at Mike Carey and my place. On Fri, Sep 22, 2017 at 6:36 AM, Paul Ruizendaal <pnr(a)planet.nl> wrote: ​The Accent system was definitely heavy on people's mind. The 1979 CMU SPICE machine proposal had made quite a splash (I should scan it, I still have an original copy). Bert Halstead and Gettys later told me the story at MIT how they had a meeting when it came out and the whole tone was 'what are we going to do what the CMU thing'​ (the result was Athena). By the time I got Berkeley, most of the community was watching what was going on. The issue in the end with Accent was that they did wrote it in Pascal and it was not done with a UNIX API base (hence Mach would be C and build into BSD). But Accent was the new cool system and UNIX was not (yet) centered as the 'the' system in the DARPA community. DARPA was still reeling from the move from the PDP-10, and a lot people were not 100% happy with that (we have been discussing rms's hating Unix and still pushing ITS as an example - he was hardly the only one). While the VAX has the HW was officially the DARPA system, Stanford was pushing for VMS if you remember. Some folks want different HW from the VAX too. CMU & MIT were pushing DARPA for the idea of person workstations (Stanford would join that too soon after an CMU EE would do his grad work at Stanford - Andy B and build the "SUN" -- taking the ideas from the old CMU distributed front-end project to a level no one ever imagined). The point is that DARPA is kinda mixed up and the politics are not as clear as it might seem 30 years later. Rashid had presented the ports idea and whole Accent network model at a DARPA PI meeting at Berkeley, I want to say in the Fall 1981-ish (date may be off by a year or two). IIRC he gave the Berkeley systems seminar that week too. All the UCB System people like me, had the paper and we were abuzz about it. Mike Powell of Cray DemOS fame, was teaching the Grad OS course and he was mixed up in the argument; as was Bart Miller (now at U Wisc) who was one of his students then. Mike has us all writing different papers and proposing different ideas. Who specifically contributed what is hard to say at this point, although Joy was the master craftsman and final author/implementor of what went into the CRSG system. At lot of test stuff was done in private code or in other UCB OS's work. But Joy was absolutely trying to come up with something for UNIX that would give a lot of the functionality of the Accent in more UNIX centric manner because he felt he needed to keep the DARPA focused on UNIX as the system of choice. Hence overlaying the file descriptor in the socket call while Rashid in Mach, would leave ports as separate concept. ​Sam is a good friend and I give him credit for many things. Primarily as making sure the BSD system worked. As I have always said about Joy, "he types open curly brace, close curly brace and he patches faster than anyone I have even known.​" So, besides mopping up after Bill, the three things I know you can credit to Sam are routed, rcp/rsh, and trailers in the headers. Besides that, he was in on everything, but what was his, what was Bills, what was someone's else's is hard. As one of my friends who did his undergrad @ MIT who was also a UCB grad student when I there put it (describing MIT's job control that Joy swiped and added to BSD), "Bill recognized a lot of great ideas and then peed on them to make them smell like UCB." ​Exactly... Although the way that worked, was actually a side effect/bug in name.​ ​It really was before 1980. Those of us that lived networking in the 70s, we were still trying to figure out what was the right way to do a lot of things. By the early 80s we agreed we had to have it, but best known methods were still off. We were still fighting the wars of SNA vs. DECnet vs Wangnet vs MAP vs YourNet vs TelCo vs .... People had not yet recognized Metcalfe's Law.​ Which really is an example of where engineers forget the technology is actually driven by economics. The 'winner' may not be the technology that is the 'best' from 'theory.' We forget that fact often on this list too I fear. I know it hurts, a number of things I have been part in my career I 'know' were 'better' than what 'won' but it does not matter. They were not economical. Clem

On 9/22/17 10:42 AM, Chet Ramey wrote: Though to be fair I think Kulp was an MIT guy who was inspired by ITS. -- ``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://cnswww.cns.cwru.edu/~chet/

Chet Ramey wrote: Yes, that's what he wrote to me when I asked him about it.

[I said] That's independent of this issue. The problem is that when you call bind(), the system does not know if you are doing it as the first half of bind()/connect(), or as the first half of bind()/listen( (followed by an accept() loop). If you are going to do the latter, you are declaring that you want to serve *new* SYN requests. This is when you (currently) must set SO_REUSEADDR, because bind() checks your local address against the universe of all local/remote pairs. But if the system knows that your call (which, remember, isn't bind() anymore) is your declaration of intent to be a server, the OS can just check whether there's already someone declared as "the server". If you intend to "serve" one specific foreign address (FTP): bind_and_connect(fd, local, remote); the test is: "does <local,remote> specify a unique address" (and possibly "does <local> match what we already suggested to you and reserved for you). If you intend to serve "*": bind_and_connect(fd, local, NULL); the test is: "is there already a <local,*>". In the server case any existing 2MSL timeouts are irrelevant; what matters is whether you are competing with another server. (Note that libc will probably have various convenience wrappers atop the system call, kind of like libc has system() atop fork/exec. Most programs just want to create and bind_and_connect a socket in one pass.) Chris

On Fri, Sep 22, 2017 at 2:14 PM, Chris Torek &lt;torek(a)torek.net&gt; wrote: ​Which is exactly my point....​As Larry said -- "*Huh, I too thought Bill Joy did it. Did he integrate it and get credit that way?"* Most people, even really smart ones that know a lot of the history like Larry, think job control came from BSD. Bill recognized a good idea (and I believe it came in on the PDP-11 version from IIASA and MIT BTW) and then peed on it as it was made part of 4.1BSD. To his credit, he was amazing at recognizing some great ideas and integrating them; and some of them make the system much more usable and I could not live without (I really would not want to type day-2-day to V6 or V7 - which I did years ago and love it ->> then <<). The core BSD system is the basic UNIX that the ROMs in my fingers and my brain expect when I'm typing. Bill was the person that shepherded it and I thank him. But it was a work of a lot people, but at UCB (and not just CSRG) and outside.

Sure, but here again you can have the shell hang on to the (kernel allocated) pgroup, and any control operation amounts to, e.g., "set tty pgroup to the one for my pgroupid X". Since the shell is waiting for everything in the pipeline to exit, the shell knows when to close its "pgid descriptor". (If you abandon the pipeline entirely, you also abandon the ability to attach it to a tty. There should be some way to "rejoin" pgroups, which would let you attach them to new tty sessions, which is something that is missing from the current system. But that's another thing entirely.) Chris