unix@cbosgd.UUCP (03/11/85)
From: Ron Heiby (The Moderator) <unix-request@cbosgd.UUCP> Unix Technical Discussions Sun, 10 Mar 1985 Volume 1 : Issue 9 Today's topics: Looking for Compupro 68K Driver Help Where does Unix use the 8th bit of chars? Need SW to control Logic Analyzer C <-> f77 Interfacing Looking for LZ Compression Implementations ---------------------------------------------------------------------- Date: 14 Feb 85 21:33:59 GMT From: stuey@wlcrjs.UUCP (Stu Heiss) Subject: help needed with 68k Here's a stickey one. I've just brought up unix on Compupro hardware with a 68k cpu using the 68451 mm. This system is not currently configurable and I need to be able to do port i/o to a foriegn board in the system. The cpu card maps memory requests to the top 64k to the i/o ports - so you have to be able to address absolute memory - which the memory management forbids. Got any ideas? What about /dev/mem or /dev/kmem? Also, I'd like to get a driver for my Sugart 4008's ready in anticipation of the reconfig files. I've got low level code written in c, but not in device driver form. I've no idea what a driver's supposed to look like - no doc on how to write one. Where do you get this kind of information? Is there any such thing as standard skeleton driver code to use as a starting point? Pleas reply with mail to ===> ihnp4!wlcrjs!stuey - Stu ------------------------------ Date: 9 Feb 85 22:17:12 GMT From: gll@sfmag.UUCP (G.L.Lindgren) Subject: Use of 8th bit in UNIX System I am in the process writing requirements for the "internationalization" of the UNIX System. One of the key ingredients in this effort is support for full 8-bit byte streams throughout the UNIX System. As many of you know, there are many areas in UNIX that take advantage of the 8th bit for local processing. For example, the shell uses the 8th bit for keeping track of quoting. *************************** I NEED YOUR HELP! *************************** I need to prepare a list of all the places in UNIX (e.g., drivers, library routines, utilities, etc) that use the 8th bit. I would also appreciate any suggestions on how these places can be changed to not use the 8th bit. If you have any information that might be helpful to me in preparing this list, I'd appreciate it. Thank you, Gary Lindgren AT&T Bell Laboratories 190 River Road Summit, N.J. 07901 ihnp4!attunix!gll 201-522-6170 x6170 sfsno!gll ------------------------------ Date: 8 Feb 85 06:08:29 GMT From: "George R. Cross" <cross%lsu.csnet@CSNET-RELAY.ARPA> Subject: Tektronix 1240 Logic Analyzer Does anyone have or know of any interesting software to control the Tektronix 1240 Logic Analyzer through the RS232 port under Unix? George R. Cross, Computer Science Department Louisiana State University, Baton Rouge, LA 70803-4020 Phone: 504-388-1495 CSNET: cross@lsu ARPA: cross%lsu@csnet-relay BITNET: cscros at nsnccvm cscros%nsnccvm.BITNET@wiscvm.ARPA ------------------------------ Date: 6 Feb 85 17:29:03 GMT From: roy@phri.UUCP (Roy Smith) Subject: F77 -> C routine communication I have a program which has f77 and C modules (main in fortran, much of the I/O in C). On the fortran side I have declared "character*512 (512)". If I want to pass this 512x512 array of characters to a C routine, how should I declare the formal parameter? -- allegra!vax135!timeinc\ cmcl2!rocky2!cubsvax>!phri!roy (Roy Smith) ihnp4!timeinc/ ------------------------------ Date: 11 Feb 85 22:35:11 GMT From: Michael M. How <OA.HOW@MIT-XX.ARPA> Subject: LZ compression algorithm Judging from recent messages, I see they is some interest in LZ compression algorithm. I would like to sum up some of the work I have done with the algorithm and exchange some ideas about implementation. Back in Oct. 1983 , Miller and Wegman from IBM Yorktown gave a talk about their extensions to the LZ algorithm. They proposed an LRU replacement to handle dictionary overflow. They also devised a string extension version of the algorithm. In particular, to form the new string to insert in the dictionary, concatenate the previous dictionary match with the match just found. This allows much faster buildup of dictionary entries. The most interesting part of their work was applying this to terminal sessions. The algorithm sat between an IBM PC and a CMS system. Results they claim are 4 to 8:1 compression, so you 1200 baud sessions look 9600. I investigate applying this to a character oriented system, UNIX in particular. Results of course are good. What I am interested is finding other implementation of the LZ compression and seeing how people handle dictionary overflow, matching. I would be interested in performance figures. The IBM implementation running on a 3081 compressed 1 million character of English text in less than 20 seconds. My version has compressed about 1000 chars/sec for 90K file on a VAX/750. In using this for terminal sessions, I would like to improve the speed on the VAX (the decompression side on the PC just rips). Thank you, Michael How ------------------------------ End of Unix Technical Discussions ***************************** -- Ronald W. Heiby / ihnp4!{wnuxa!heiby|wnuxb!netnews} AT&T Information Systems, Inc. Lisle, IL (CU-D21)