vandys@Lindy.STANFORD.EDU (Andy Valencia) (06/09/87)
From: mcvax!stc-c!reza@seismo.CSS.GOV Date: Mon, 8 Jun 87 18:25:53 -0100 To: vandys@lindy.stanford.edu Subject: Multiuser MINIX I am very much interested to know how to get an IBM PC/AT running MINIXr. I would appreciate any help you could give to me. Thanks, Reza Fardoom STC Telecommunication Ltd, London Sorry to bother everybody, but (1) mcvax doesn't know from "stc-c", and (2) perhaps my RS-232 posting gave all the right software but none of the right information. I will try to make amends. First, in case it got lost somewhere, the RS-232 driver for MINIX was posted a bit more than a week ago. If you didn't get it, and want it, please mail me. I will re-post or mail direct, based on head count. How to get a second user on your PC (or AT, makes no difference): 1. Verify that your serial port works I am talking about your standard IBM-PC COM1: port. Boot up DOS and run a terminal emulator. Plug a modem into the port, make a call via the modem. When this works, you're ready to go on. Incidentally, if your modem has straps for such things, set it to 300 baud. 2. Install the diffs indicated If you don't understand the diffs, find a UNIX guru and have them explain it to you. 3. Re-build As recommended by AST himself, re-build your kernel without changes before trying to re-build WITH changes. The procedure is in the book, and tends to work. Don't forget to make the library module setpgrp.c, and to recompile init.c! 4. Add a line to /etc/ttys This file is read by init to tell which tty lines need to have a login: prompt put on them. The file should be a single line, "100" This enables your console port. Add a line "101" to enable the new TTY port, then write this file BACK TO FLOPPY DISK (/etc/ttys is just a copy of it on the RAM disk). 5. Make a device special file for the new TTY Let's say your mounted your root file system in step (4) above onto /user. You've just copied /etc/ttys to /user/etc/ttys. Before umount'ing the disk, run the command % mknod /user/dev/tty1 c 4 1 This creates tty1 with major number 4 (the TTY driver) and minor number 1 (tty1, the RS-232 driver). Do NOT try: % mknod /dev/tty1 c 4 1 % cp /dev/tty1 /user/dev/tty1 as this will try to open /dev/tty1 and read data from it. We want to create a device entry on the floppy, not copy the device's data! 6. Reboot Unmount & sync after step 5! When your system is coming back up, right after it prompts for the date & time "login:" should be printed on your /dev/tty1 port. Login should proceed normally on either port. 7. Problems I wish I could be more helpful. The TTY scheme under MINIX is a nightmare. The most common sort of "crash" is where FS or MM gets blocked on TTY, and TTY doesn't answer. Follow the code paths by eye while considering what you did right before the lock-up. Add printf()s at strategic points, recompile and try again. I bought an Orchid accelerator for my XT so that this cycle wouldn't drive me mad with its slowness (it works fine, once you've installed the excellent xt_wini.c fixes posted a while ago). It still drove me mad. Good luck, Andrew Valencia vandys@lindy.stanford.edu br.ajv@rlg.BITNET (415)329-3524 work
squibby@eleazar.dartmouth.edu (Clark L. Breyman) (02/16/90)
I'm interested in possibly using Minix for a college radio station system and need some info on multi-user minix (pardon my general ignorance on minix): Do all versions of Minix support multiple users? How many? Do the memory constraints become a problem? Can the ST support more than the console and the RS-232? What sort of computing horsepower is needed for 2 users (Would a 8MHz PC w/640K be OK?) 4 users? Have drivers for multiple serial ports been written for Minix 86? Thank you very much, C Breyman squibby@do.ucsd.edu squibby@dartmouth.edu