TUHS

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6557 discussions

Re: [TUHS] Ethernet in /dev (was Re: Were all of you.. Hippies?)

by Norman Wilson

Joerg Schilling: This is done on a UNIX implementation that uses STREAMS. SVr4 is such a UNIX. ====== I know that SVr4 has STREAMS (somewhat more elaborate than the original stream I/O system, but the same principles), and knew (though I'd forgotten) that Ethernet devices are stream-capable. I did an implementation of the late lamented Coraid's AoE protocol that took advantage of that. Somewhat like the Research IP implementation, in fact: there was an AoE line discipline to be pushed … [View More]

8 years, 4 months

Re: [TUHS] Release of 8th, 9th and 10th Editions Unix

by Norman Wilson

Arnold: > Well, I'll take credit for pushing Norman yet again. :-) ARGGH. That should have been Well, I'll take credit for pushing Warren ... ^^^^^^ ===== I confess I didn't notice the fumble the first time. But in fact Warren has had the dubious pleasure of pushing me for something more than once. So just think of it as another level of indirection. Norman Wilson Toronto ON

8 years, 4 months

Re: [TUHS] Ethernet in /dev (was Re: Were all of you.. Hippies?)

by Norman Wilson

Ron Natalie: It's a violation of the network layering concept to require or even allow the user to bind the application data streams to a physical device. ===== Oh, come on. If you mean an applications programmer shouldn't have to wallow in low-level network details, I agree. That's one of the reasons I think the socket interface now standard in nearly every UNIX is an abomination. It reminds me of the binary data structures you had to assemble just to open a file in TOPS-10, only ten … [View More]

8 years, 4 months

Ethernet in /dev (was Re: Were all of you.. Hippies?)

by Norman Wilson

Josh Good: Which brings up a question I have: why didn't UNIX implement ethernet network interfaces as file names in the filesystem? Was that "novelty" a BDS development straying away from AT&T UNIX? ====== Remember that UNIX has long been a family of systems; it's risky to make blanket statements! The following is from memory; I haven't looked at this stuff for a while and am a few kilometers from my manuals as I type this. I can dig out the complete story later if anyone wants … [View More]it; for now, this is just the flavour and the existence proof. Research UNIX, once it supported Ethernet at all, did so using devices in /dev; e.g. /dev/qe0[0-7] were the conventional names for the first DEQNA/DELQA device on a MicroVAX. There were eight subdevices per physical device, each a channel that might receive datagrams of a particular 16-bit type, programmed by an ioctl. To set up what we now call an IP interface, one did the following: a. Open an unused channel for the proper Ethernet physical device. (I think the devices were exclusive- open to make this easier: open /dev/qe00, then qe01, and so on until one succeeds.) b. Issue the ioctl to set the desired datagram type, usually 0x800. c. Push the IP stream line discipline onto the open file. d. Issue an ioctl to inform that IP instance of its address and netmask. Now datagrams of the specified type arriving on that device are fed to the IP subsystem, and the IP subsystem uses the IP address and mask and possibly other information to decide which datagrams to route to that IP instance, which sends them out that physical device. I forget how ARP and Ethernet encapsulation fit in. I know that they were someone more naive early on, and that in the 10/e systems I can now admit I have running at home I made things a bit smarter and less brittle. But that's the basic architecture. So how does one actually make, say, a TCP connection? Another layer of the same sort: There are devices /dev/ipX, served by an IP device driver that is part of the IP subsystem. Originally minor device X was hard-connected to IP protocol X; I later changed that to be ioctl-configured as well. To make TCP usable: a. Open /dev/ip6 (old school), or find an unused /dev/ipX (again they are exclusive-open) and configure it to accept protocol 6. b. Push the TCP stream line discipline onto the open file. c. There are probably things one could then configure, but I don't remember them offhand. To make a TCP call, open an unused /dev/tcpNN device; write something to it (or maybe it was an ioctl) with the desired destination address; wait for an error or success. On success, writes to the file descriptor send to the network, encapsulated as a TCP stream; reads receive. To receive a TCP call, open an unused /dev/tcpNN device, and write something (or ioctl) to say `I want to listen on this local port.' Then read the file. When a call arrives, you will read a message saying who's calling, and what /dev/tcpXX device you should open to accept the call. Notice the general scheme: for both TCP and IP (and there was a primitive UDP at one point, but it has fallen out of use on my systems), the protocol implementation comprises: 1. A line discipline: push it onto devices that will transport your data. 2. A device driver: use those devices to send and receive calls. The two are inextricably coupled inside the operating system, of course. There are all sorts of unfortunate details surrounding communications; e.g. the TCP code knows it is talking to IP, and constructs datagrams with partly-filled-in IP headers. (It is not clear one can do better than that in practice, because the protocols themselves really are linked, but I still think it's unfortunate.) On the other hand, that the junctions between plumbing are accessible makes some things very simple. I wrote a PPP implementation in user mode, with no kernel changes: to plug itself into IP, it just pushed the IP line discipline onto one end of a pipe, and read and wrote datagrams on the other. I later extended it to PPPoE by having it open an Ethernet device set to the proper datagram types (there is one for data and another for connection setup). On the other other hand, there are no permissions on stream line disciplines, so an untrustworthy person (if I allowed such on my systems) could push the IP line discipline onto his own pipe and send whatever datagrams he liked. This is decidedly a flaw. Those familiar with the original stream-system implementation have already spotted a lesser flaw: the file descriptor with IP pushed on (or TCP, or whatever) must remain open; when it is closed, everything shuts down. In practice it is usually useful to have a daemon listening to that file anyway; that's a good way for the system to report errors or confusion. In practice, TCP incalls and outcalls all went through a special daemon anyway, so that programs didn't have to be full of TCP-specific crap; that's what Dave Presotto's `connection server' is all about. Norman Wilson Toronto ON [View Less]

8 years, 4 months

Re: [TUHS] 8th Edition Research Unix on SIMH

by Jason Stevens

Thanks for the hints, and whatnot... I got v8 running! > ---------- > From: Tim Newsham > Sent: Wednesday, March 29, 2017 7:50 AM > To: David du Colombier > Cc: The Eunuchs Hysterical Society > Subject: Re: [TUHS] 8th Edition Research Unix on SIMH > > Would be great if someone scripted it up to make it dog-simple. > Here's how I did it for v6: http://www.thenewsh.com/~newsham/myv6/README > (I should do this, but I'm not sure I'll have time in the near … [View More]

8 years, 4 months

Searching for 9th Edition Research Unix mail / Mail / mailx

by Steffen Nurpmeso

I am maintaining a BSD Mail derivative and one goal of the project is to have the complete history of Unix mail and BSD Mail in the repository. There yet exists a [timeline] branch, which has been fed with data from TUHS (thank you!) and CSRG; but it is coarse and further linear history and so the new V8 and V10 cannot be inserted, i will need to add new [unix-mail] and [bsd-Mail] (and maybe [bsd-csrg] with all commits preserved, like Spinellis did so in the Unix-history repository). Thanks … [View More]

8 years, 4 months

Release of 8th, 9th and 10th Editions Unix

by Warren Toomey

All, today after some heroic efforts by numerous people over many years, Nokia-Alcatel has issued this statement at https://media-bell-labs-com.s3.amazonaws.com/pages/20170327_1602/statement%… Statement Regarding Research Unix Editions 8, 9, and 10 Alcatel-Lucent USA Inc. (“ALU-USA”), on behalf of itself and Nokia Bell Laboratories agrees, to the extent of its ability to do so, that it will not assert its copyright rights with respect to any non-commercial copying, distribution, performance, … [View More]

8 years, 4 months

Re: [TUHS] 8th Edition Research Unix on SIMH

by jnc＠mercury.lcs.mit.edu

> From: Tim Newsham > Would be great if someone scripted it up to make it dog-simple. But if people just have to press a button (basically), they won't learn anything. I guess I'm not understanding the point of the exercise? To say they have V6 running? So what? All they did was press a button. If it's to experience a retro-computing environment, well, a person who's never used one of these older systems is going to be kind of lost - what are they going to do, type 'ls -ls' and look … [View More]

8 years, 4 months

Re: [TUHS] 8th Edition Research Unix on SIMH

by jnc＠mercury.lcs.mit.edu

> From: Grant Taylor > However, I've had to teach enough people to know that they need a way to > boot strap themselves into an environment to start learning. Right, but wouldn't they learn more from a clear and concise hand-holding which explains what they are doing and why - 'do this which does that to get this'? There is no more a royal road to knowing a system, than there is to mathematics. > I do consider what (I believe) Warren put together for the UUCP project … [View More]

8 years, 4 months

Re: [TUHS] Happy birthday, PDP-8!

by Johnny Billquist

On 2017-03-28 09:37, jnc(a)mercury.lcs.mit.edu (Noel Chiappa) wrote: > > > From: Johnny Billquist > > > the PDP-11 have the means of doing this as well.... If anyone ever > > wondered about the strangeness of the JSR instruction of the PDP-11, it > > is precisely because of this. > > ... > > I doubt Unix ever used this, but maybe someone know of some obscure > > inner kernel code that do. :-) > > Actually Unix … [View More]

8 years, 4 months

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TUHS