Brasstacks

I've been playing around a bit more with the Incompatible Timesharing System (ITS). I figured out enough networking on my Mac to be able to use the Java Supdup terminal application to interact with KLH-10 simulating the KS10 architecture. As part of my study, I have also been converting some INFO files to Texinfo, starting the with the file (slow link to UP.update.uu.se ITS system) INFO;DDT > which Bjorn Victor converted to an HTML version: DDT Primer ). I like Texinfo because it can (theoretically) print nice looking books for an ebook reader like my new Kindle Paperwhite, as well as Info compatible for Emacs navigation, and HTML. Actually distributing these files is problematic. ITS generally seems to have operated with a pretty free notion of distribution: send a magnetic tape to pretty much anyone with a PDP-10 who asked, without executing any kind of explicit license agreement, or even having copyright notices on the text. Anyone with access to the system could take i...

OK, so ITS has only one level of directory in its file system, otherwise known as the SNAME portion of a filename. How do you create a directory if there isn't one already? For instance, if you login as an unknown user JAO and ITS complains it can't find MD:USERS1;LOGIN JAO , and Emacs won't let you create a file USERS1;LOGIN JAO because USERS1; doesn't exist, what do you do? I expected there to be a DDT command to create a directory. But there isn't one. I found a cryptic comment to "look at the documentation for the OPEN UUO." So I did. Examining SYSDOC;_CALLS.124 The file names ..NEW. (UDIR) cause a new directory to be created with the given sname if none already exists. Creating a directory in this way causes a message to be printed on the system console. (A directory is destroyed only when the disks are salvaged by the stand-alone salvager, which is generally run just before the time-sharing system is restarted. A directory is then destroy...

I've cycled back to being interested in the Incompatible Timesharing System (ITS). In the interim, I replaced my G4 iBook with a Intel-based MacBookPro. With a bit of hacking, I was actually able to get local networking to communicate with the simulated PDP-10, and thought I would record some of the details. I needed to Install tuntaposx . I used the macports version. Crudely hack the ks-base-its build in klh10-2.0h from panda-dist (and additional patches) to define KLH10_NET_TUN=1 under Mac OS X. I need to clean up my own sources and put them up on github. Also, I needed to hack around the removal of "mtio.h" from Mac OS X 10.6, borrowing the minimum definitions from FreeBSD headers. I guess Apple decided they really didn't want tape drives connected to their machines. Maybe it is still in OS X server? There are a few rough edges in tun/tap support. Following a hint I found online, I open a bash shell as root, and execute exec 4<> /dev/tap0 # create t...

This is not particularly interesting, but I wanted to record a couple of links to ChaosNET code for the PDP-10. The ChaosNET memo describes an ITS (Incompatible Time-Sharing System) interface, for which the code is somewhere in the ITS sources, and a Lisp Machine implementation, for which code is in the CADR sources and Symbolics code base, but also a TOPS-20/TENEX implementation, a VMS/VAX implementation, and a UNIX implementation. The UNIX implementation was documented by James E. Kulp for Symbolics, and the code seems to have survived. The TOPS-20/TENEX is harder to find, but it looks like BitSavers' Foonly archives have some files. DSK:<FOONEX>CHAOS.MAC;399 DSK:<FOONEX>CHABUG.MAC;8 DSK:<FOONEX>CHAOS0.MAC;3 DSK:<FOONEX>CHATTY.MAC;21 I have no idea whether this is at all related to the implementation the AI MEMO mentions. A Google search turns up some interesting code (might be for the PDP-11 front end, for ITS) from AI:SYSTEM CH10.defs1 ...

My blogging has been much less frequent of late, mostly because of an unfortunate abundance of non-computer issues. Despite those, I believe I have made some progress in my Chaosnet-on-OpenMCL work, but I've switched most of my hobby-development to Python, mostly to get in touch with trends outside the Lisp Universe. My current main project circulates around ChaosNET emulation; the main thing going for Python here is a socket interface that is roughly compatible between UNIX-like and Windows operating systems. Lisp can support that as well, but not for my favorite and familiar implementations. (One thing I hope to try before I get through this is to get an asyncore-like framework set up in CLISP.) So far, I have implemented a `chaosd' process in Python that simulates multiple ChaosNET `ethers' in the form of localhost TCP streams (on Windows or UNIX-like) or UNIX-domain sockets (on UNIX-like); each stream corresponds to a subnet. The idea has manifold goals: Allow the...

A bunch of stuff I was reading back then Weak Data Structures write-up by Bruno Haible, courtesy of Gary King . The classic UNIX HATERS Handbook. Panda's TOPS-20 System. Spare Time Gizmos store front to buy actual hardware emulators of the PDP-8. Rainer Joswig e-mail on feel of old Symbolics Lisp Machines An e-mail discussion about CHAOS vs. TCP in port collisions, a list of Symbolics CHAOS services Google cache of mahalito Symbolics Y2K statement ITS site HACK directory Google Groups discussion on Basic Chaosnet information Google Groups discussion on Chaosnet and ARP Google Groups discussion on Transmitting Chaosnet over Ethernet Google Groups discussion on Why Chaosnet (nostalgia) Google groups search for chaosnet ITS build information build.doc.txt 36bit.org Retro PDP-10

Wanted to collect a few links on ITS, the Incompatible Time-Sharing System The ITS 1.5 Reference Manual Bjorn Victor's Luser's Guide Bjorn Victor's e-mail setup (perhaps useful information for Lispm Zmail setup) The KLH10 PDP-10 emulator More information on PDP-10 emulation The www.its.os.org archive of AI & MC Paul Svensson's ITS system on the Web