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Getting Started Computing at the Al Lab by Christopher C

1. Getting Started Using TOPS 20 Page 53 another machine 7 9 2 Comlinks Comlinks are the most interactive way of communicating with another user on Tops 20 When two users are in a comlink they will each everything which is being displayed on any of the consoles Since a comlink will interrupt whatever a person is doing you should probably SEND to the person asking if it is OK to link first To establish a comlink with another person use the talk command talk name f This will link your terminals together Each person in the link takes turns typing When you are done saying something type a blank line to let the other person know you are finished Since you probably do not want to type commands to your EXEC during a comlink you should type the REMARK command Link from JFC TTY10 GremARK mode Type Remark End with 2Z this is a comment Ihis is another comment 9 The person who you linked to will also have to type the REMARK command When you are done conversing type tz and the break command z l breAK links with Q There is an etiquette for talking to people in comlinks Because a comlink is a pretty violent interruption you should usually ask someone with a send for permission to enter a comlink Each person in the link takes turns typing When you are done saying something type a blank line to let the other person know you are finished If you are in a multi way comlink you should sign your na
2. 7 September 1982 Geiting Staried TW ddtsym ttytyp if e q amp lt Ztysty Ztydil gt jump mail ddtsym tctyp if e q tnsfwo jump mail tVOn a Concept tw if more 0 1VYestWS tctyp c100 jump hack 1VNotW 1TVVT100 WS if more 0 1VYestWS crtsty vt100 jump hack 1VNotW tag hack self delwarn 2 morwarn 0 sndflg 1 byerun 1 kill gmsgs D vktV UsingiTS Figure 6 2 Sample DDT init Page 36 Z Cardnmik m OUO Getting Started Using ITS Page 87 6 9 Inquire To make an Inquire entry on ITS run the INQUIR program The WHOIS command will print on your terminal all the inforrhation associated with a user in the ITS Inquire database A single Inquire database is shared between all the ITS machines if you are known on one ITS you are known on all of them Example whois kwh KWH A Ken Haase Last logout 6 23 82 No plan Ken 02 Hacking amateur systems for Minsky Birthday December 3 NE43 352 3 1728 Home phone 491 0012 Senior House 4 Ames St Cambridge MA 01239 Smile Numerous commands and programs exist to see who is logged in The most common ones are WHOJ and FINGER Example whoj T24 XGP XGPSPL T43 DCB TEX T53 CSTACY EMACS T56 KEW R T67 CARL HACTRN KILL finger User Full name Jobnam Idle TTY Console location XGP O Xerox Graphics Printer XGPSPL 26 T24 Datapoint Near XGP DCB Dan Brotsky TEX TA3 NE438A
3. 8 23 82 PGS SYSENG 3 PEEK 474 22 616 10 30 81 00 68 18 4 13 82 MOON KILL 6 7 Terminal Support ITS is a designed for use with display terminals If you are using a hardwired terminal a Knight TV or are using the SUPDUP protocol across a network ITS will usually already know your terminal s Me characteristics However coming from a dialup line or a TELNET connection such as an ARPAnet TAC ITS will need to be informed about your terminal ITS provides support for a variety of terminals through two programs TCTYP and CRTSTY The TCTYP command is for terminals which ITS knows about natively while CRTSTY is used for more complicated support and display optimization TCTYP will aseeni a simple Inu which specifies the type of terminal you have such as a Concept 100 tctyp c100 KILL TCTYP also understands more complicated specifications A very simple example of this is telling the system how many lines your screen has On some terminals for instance an Ann Arbor Ambassador giving this specification will cause ITS to transmit the codes necessary to actually set the size you want tctyp aaa height 48 KILL Giving the command stctyp 7 September 1982 Getting Started Using ITS Pages will cause TCTYP to list the terminals and options which it understands The CRTSTY program works by logging you in on an additional job and intercepting and translating your input output stream to the system This
4. 814 Brotsk CSTACY Christopher C Stacy EMACS 153 914 Greenblatt x67 KEW Karen E Wieckert R T56 819 Davis x5879 CARL Car Hewitt HACTRN 167 813 Hewitt x5873 PGS Patrick Sobalvarro CADR25 902 Robot room x67 KMP Kent M Pitman CADR22 339 Sorcerer s App DPH Daniel Huttenlocher CADR21 722 FPS Express x6 GREGOR B Gregor Kiczales CADR20 2 706 Educational Co ECC H Eugene C Ciccarelli CADR18 907 CADR 1 s room LEVITT David Levitt CADR 9 721 Music Hacker s PGS Patrick G Sobalvarro CADR 7 936 LispM Factory HENRY Henry Lieberman CADR 4 14 912 Lounge Lizard NIS Keith Nishihara CADR 3 903 Vison x6765 DANIEL Daniel Weise CADR 1 907 Son of CONS 6 10 Communication On ITS there are three basic ways to communicate with other users comlink sends and mail Each of the three ways is best suited to a particular type of interaction 7 September 1982 Getting Started Using TS Page 38 6 10 1 SENDs The SEND command is available for sending user a quick interactive the other user must be logged in message To get the fancy version of SEND which understands about talking to multiple networks be sure to set the SNDFLG variable as shown in the sample DDT init file above Simply type the command SEND followed by the uname of the person you wish to send to a SPACE or carriage return and your message Your message may be as long as you like to end it type control C Example send levitt Is the music room free right now tC I
5. TECO 16 Tectronix 5 TELNET 8 13 Terminals 6 TEX 17 Text justifiers 17 Timesnharina 3 TIP 12 Tops 20 3 TVs 22 Twenex 3 Typesetting 17 Unprotect 44 User groups 45 VAX 3 Versatek 5 WHOIS 37 51 Wholine 34 Window 19 XGP 5 32 Zmacs 16 ZORK 25 Zwei 16 21 7 September 1982
6. The DIRECTORY and VDIRECTORY verbose directory commands are usful for seeing which files are in a directory The DELETE command deletes files The EXPUNGE command gets rid of deleted files in a directory The COPY command makes copies of files and the RENAME command changes a file s name You can move files around in the file system with these commands but the RENAME command will not move a file across a disk device 7 6 6 Hardcopying files To send a file to the Dover printer use the DOVERSEND program If the file is not already in press format you will need to use the PRESSIFY program first These programs are selt documenting 7 6 7 Creating Directories A directory has a name and some attributes These attributes determine such things as whether the directory can be used to login with how much space the files in it can consume and what groups it is part of 7 September 1982 Getting Started Using TOPS 20 Page 50 To list the attributes of a directory use the INFO DIR command Example info dir lt pa gt Name PS lt PA gt Working disk storage page limit inf Permanent disk storage page Timit inf Creator of login subdirs Login subdirs allowed Number of directory 720 Account default for Login none set Maximum subdirectories allowed 967 User groups 120 Directory groups 120 The quota attributes such as the amount of disk used are typically some very large number displayed as inf This is
7. because most users on OZ have no interest in arbitrary limits to the amount of storage that lab members use The BUILD command allows you to make new directories and to alter the attributes of existing directories build ps Kjdo thesis Once inside BUILD mode you can enter Build subcommands Type LIST VERBOSE at BUILD to see what the different characteristics of the directory you can modily When you are done in BUILD mode type RETURN twice to exit back to the EXEC One interesting paramter to set with BUILD is GENERATIONS TO KEEP This variable says how many versions of a file to let you write to disk in the directory If this number is zero any time you write a new version of a filem it is stored on disk If this number is positive number n only the most recent n versions of your file will be availabte the old generations are automatically deleted when you write out a new one 7 6 8 Changing Passwords To set the password on a directory use the SET command set dir pass lt danny gt Old Password New Password Retype new password When the Protector facility is fully operational the capability to create toplevel directories and login able subdirectories will be restricted from users and new commands will be introduced 7 September 1982 Getting Started Using TOPS 20 Page 51 7 7 Terminal Support f The version of Tops 20 which runs on OZ has been enhanced to provide some support for display term
8. can serid mail askirig to be put o mailing list To get on a mailing list you should usually not send mail t the list itself This is especiafty true of large mailing lists where the many people on the list are normally uririterest d i th comings and goings of the audiance Except for BUG mailing lists most mailing lists of much size have a maintainer who is reponsible for adding and defetirig people from the list as they request By convention the maintainer of the FOOBAZ list can be reach d by sending mra fo FOOBAZ REQUEST d Sometimes an archive file is set up as a recipient on a mailing fist ff a matting list has a archive you can delete your copies of the messages assuming you received thier arid refer to the ones in the archive instead This saves disk space and preserves the discussioris for posterity x 7 Santambher TARF Getting Started Networks Paget 2 5 1 BBoards Electronic Bboards are similar to electronic mail but are used for one way announcements instead of conversations BBoards can be conceptually divided into two categories system messages which everyone should see and other stuff Certain BBoards are used for just System Messages Good relations among users rely in part on people not being inundated with junk mail system messages which go to inappropriate addresses are junk mail System Messages are items like listings of Lab seminars and machine maintenance schedules Other Stuf
9. means that it uses up an additional job slot and n additional virtual port STY on the machine There are a limited number of STYs on the machine Entering the command crtst will make CRTSTY print out what options it supports 6 7 1 Wholines if you are not using a Knight TV and still desire a wholine on your screen there are some programs to provide one The WHOLIN program works on most terminals while the H19WHO puts a wholine on the 25th line of an H19 terminal The VTTIME program will put time of day clock in the lower right corner of your screen Finally an argument of wholine to the CRTSTY program will provide a CRTSTY user with a wholine 6 8 Customization Customization involves some slight magic If you find this section confuing don t hesitate to get a more experienced user to help you I There are a number of variables in your DOT which control the exact behaviour of some of your commands You can set these by telling DDT to make itself the current job with the SELF command To poke the desired value into the variable type the name of the variable a slash the value and a carriage return One of the interesting variables is called DEL WARN A non zero value for DELWARN will enable the short form delete command By setting it to the value two 2 you will also make DOT print a brief explanation of what it will do it you press return In this example we will set the DELWARN variable type a short form PRI
10. researchers about all kinds of things For example personal messages to other ARPAnet subscribers for example to arrange a get together or check and say a friendly hello are generally not considered harmful This is one of the ways in which we adapt the network environment to our community It is very clear that without that sort of freedom the network could not have evolved to its current point of technical and social sophistication Sending electronic mail over the ARPAnet for commercial profit or political purposes is both anti social and illegal By sending such messages you can offend many people and it is possible to get MIT in serious trouble with the Government agencies which manage the ARPAnet 7 September 1982 Getting Started Networks Page 10 2 5 Mailing Lists A mailing list is a collection of individual network addresses called by a single name Mailing lists are useful ways of dissemenating information to specific groups of people Through years of experimentation on the ITS computers and its advanced mail software MIT pioneered the development of mailing lists Mailing lists have come from the realm of novelty to be recognized as an important research tool used every day Some mailing lists are somewhat private and are intended for communication between pecific group of people Most mailing lists however are public and anyone can join then Some mailing lists are quite large a few mailing lists have se
11. resources The Lisp system software for the Lisp Machine was originally written at the Al lab It is being continually enhanced and improved by both people at the fab and by outside companies who manufacture Lisp Machines Lisp Machines use special consoles with hi resolution bit mapped displays and fancy keyboards and little boxes known as mice which are fun to roll around on tabletops Some of the Lisp Machines are equipped with high resolution color displays Our current LispMs were constructed at the laboratory there are plans to purchase many additional machines which feature an improved hardware design from outside the lab in the near future Some of the LispMs have Floating Point Systems hardware attached to them These peripheral processors can be used for certain types of number crunching For example the FPS boxes are used for doing some of the computations required for speech analysis One Lisp Machine CADR 27 has been dedicated as a central Filecomputer The Filecomputer has several 300 megabyte disk drives attached to it and represents a butk repcsitory for files 7 September 1982 Getting Started Introduction Page 3 1 2 Timesharing Currently the Al lab has two large timesharing computers available for general use by lab members These two machines computers provide laboratory members with netwdrk access central file storage document preperation facilities and software development tools MIT AI0 is a modifi
12. the same as her login name on PS structure A feature of files on Tops 20 is that they do not necessarily go away when deleted To make a file really go away from disk you need to expunge the directory the file is in Sometimes when the system gets low on disk space it will expunge your deleted files for you The EXPUNGE command expunges directories Gexpunge lt mumb e gt PS lt MUMBLE gt 33 pages freed In Tops 20 there is the notion of a connected directory When a user is connected to a directory he enjoys all the access rights of the directory ewner The directory you are connected to when you log in is your own directory on the PS structure 7 6 2 Subdirectories Tops 20 supports subdirectories which allow you to group related files together and help manage your directory A subdirectory is pretty much like your toplevel directory and has a name which looks something like lt YOURNAME F00 Subirectories make files on the system appear to be tree structured The top node in the three is the lt ROOT DIRECTORY gt From this root at the apex individual directories belonging to users emerge Underneath a user might be additional directory nodes Many users find that subdirectory nodes help them to organize their files 7 6 3 Logical Names A logical name can be thought of as a way of referring to a particular set of files by an alias Logical names are especially useful if you dont want to specify the name of a di
13. 2 Getting Started Using ITS ITS 1279 7 27 82 3 38 05 TVS 8 11 USERS 14 0 23 User Full name Jobnam Idle XGP Q Xerox Graphics Printer XGPSPL DCB KLH KLOTZ KEW SHIM MINSKY GJS RICH PHW RMS POGGIO CARL PGS KENT KMP DPH GREGOR B ECC H LEVITT PGS CSTACY HENRY NIS AGRE DANIEL System up time 3 15 48 Free Lisp Machines Dan Brotsky Ken Harrenstien Leigh L Klotz Karen E Wieckert Shimon U11man Marvin Minsky Gerald J Sussman Chuck Rich Patrick H Winston Richard M Stallman Tomaso Poggio Carl Hewitt Patrick Sobalvarro Kent Stevens Kent M Pitman Daniel Huttenlocher Gregor Kiczales Eugene C Ciccarelli David Levitt Patrick G Sobalvarro Christopher C Stacy Henry Lieberman Keith Nishihara Phil Agre Daniel Weise TEX MIDAS TECO Happy Birthday to SUNNY and MOBIUS 26 CADR 8 747 CADR19 361 TTY T24 T43 144 T55 156 T57 T60 T61 T62 T63 T64 T66 T67 Page 23 42 SB 0 PG 0 CORE 0 365 43 Console location Datapoint Near XGP 9th NE438A 814 Brotsky Net site SRI NIC 926 Sealy x6765 819 Davis 5879 822 Ullman x5033 750 Minsky x7807 356 Sussman x6874 342 Rich x7877 817 Winston x6218 914 Stallman x2076 822 Poggio x5226 813 Hewitt x5873 902 Robot room x6765 903 Vision x6765 339 Sorcerer s Apprentice 722 FPS Express x6765 706 Educational Computing 907 CADR 1 s room x6765 721 Music Hacker s Hangout 936 Lisp
14. COM source comparator on ITS and Twenex is a handy tool for doing automatic comparisons of source files to find the differences between them The Lisp Machine has a SRCCOM prograin as part of the DIRED subsystem in Zmacs 3 4 ATSIGN The ATSIGN program generates program listings with nice cross references and symbol tables for several languages including Lisp ATSIGN will handle multiple fonts mutiple tiles and makes nice crossreference charts 3 5 Text Justifiers There are three text justifiers which are popularly used by people at the Al lab 1 Tex is a very powerful typestting system written by Don Knuth at Stanford It is especially good for doing complex mathematical typsetting 2 R is a text justifying system which is designed to be very flexible Such features as multiple environments and macros are provided R is available under ITS Tops 20 Unix and VMS Documentation for R is available in INFO 3 The SCRIBE document production system was developed at the Computer Science Department of Carnegie Mellon University Getting Started Computing at the Al Lab was prepared using SCRIBE and camera ready copy was printed on the Dover printer SCRIBE is available under ITS Tops 20 and on the VAX 3 6 SPELL The SPELL program on ITS called ISPELL on Tops 20 will check the spelling of the words in a file This is an amazingly handy tool for preparing papers More information about SPELL can be found through INFO 3 7 Macsyma
15. DELETE is tO control o which works like R does for PRINT Because you could easliy delete a file accidently this short form does not work unless you set a customization vatiable explained later which enables the command To rename a file you can use the RENAME command H takes two file names seperated by commas an initial file name and a new file name Example rename foo bar baz foo new name A related command is the MOVE command The MOVE command will rename a file between directories or across devices This is sort of like renaming except that it actually copies the file and then deletes the original To copy file you can use the COPY command Example copy foo bar baz fred bar baz Both MOVE and COPY will copy across directories or devices but RENAME will only rename a file in the same directory 6 6 2 Hardcopying files The DOVER program and the XGP program can be used to print files on the repsective hardcopy peripherals Each of these prgrams expects a file name as an argument 7 September 1982 Getting Started Using ITS Page 33 dovor james sprite gt Attempting Chaosnet transmission KILL 6 6 3 FIND You can find files whose names match certain patterns by using the FIND program FIND is documented in INFO Example find yg ee peeses AI SYS 2 PDP10 DDT 3 9 2 71 18 40 00 6 27 82 5 PURQIO 2122 67 307 2 19 82 04 23 48 8 23 82 JONL AI SYSBIN 4 PEEK BIN 9 297 8 9 82 03 02 07
16. KS 432400 1 130 13 1200 2 200 6 212 152000 1 MYCRFT LOGIN 1 6 16 82 06 02 20 1 MYCRFT EMACS 2 6 16 82 07 32 20 1 MYCRFT MAIL 18 6 17 82 05 16 01 13 MISPU 14 20 7 28 81 09 12 40 3 MISPU 20 22 103 7 28 81 02 07 08 6 FROB BAZ 1 1 12 82 04 22 34 1 THESIS TEX 45 6 16 82 12 02 01 1 THESIS PRESS 102 6 16 82 14 37 00 15 URSLA LEGUIN 1 5 16 81 01 50 23 Figure 6 1 ITS directory listing 7 September 1982 Getting Started Using4 TS Page 32 The above sample directory listing of a mostly empty directory illustrates the LISTF command Listed is the name of the directory the number of free disk blocks on each pack the pack which each file is on the name of the file iis length in piocis and its creation date A disk block on ITS is around 4K characters long 6 6 1 Useful File Manipulation Commands The short form of LISTF is F control F To list the KMP directory type the command KMPIF A variant on LISTF is useful for listing related files in a directory To list only those files which have an FN1 of JUNK you can type the command JUNKS tF junk ALTMODE ALTMODE control f To print the contents of a file on your terminal you can use the PRINT command Example print foo bar baz The short form of PRINT is R control R to print the file named FOO BAR BAZ type tR FOQ BAR BAZ and press the RETURN key l To delete a file from the system you can use the DELETE command Example delete foo bar baz The short form of
17. M Factory x6703 726 Spacy x7710 912 Lounge Lizard Lispmacho 903 Vison x6765 751 VLSI Lounge x7837 907 Son of CONS x6765 Last updated at 3 49 26 XGP idle CADR23 822 Figure 5 1 The Name Dragon s Free Display 7 September 1982 Getting Started Using ITS Page 24 Command F cs Knight TV commands Description Show the Name Dragon display Finger This command will Switcly your TV so thak instead of looking at your own display buffer it sees the Free display Switch frame buffer Spy This command will switch your TV to yoyr own display buffer which is useful if you were looking at someone else s If you type a number before the S yous TV will be switched so that you see that TV buffer number Complement white on black actually its green on black mode Buzz open the ninth floor door Your screen flashes when the door has been buzzed Summons the elevator to your floor Your screen flashes when the elevator has been called Copies your screen to the 8th floor Tektronix copier Your screen flashes when the TV has grabbed the image for the copier l Clear yaur scroll register You should never need ta do this Select an audio channel to tisten to This usually doesn t work anymore Clear screen without telting the PDP 10 Control the wholine Control the wholine Figure 5 2 Knight TV commands 7 September 1982 UT Getting Started Using ITS Page 25 6 Using IT
18. MASSACHUSETTS INSTITUTE OF TECHNOLOGY ARTIFICIAL INTELLIGENCE LABORATORY WORKING PAPER 235 7 September 1982 Getting Started Computing at the Al Lab by Christopher C Stacy M Abstract This document describes the computing facilities at the M LT Artificial Intelligence Laboratory and explains how to get started using them It is intended as an orientation document for newcomers to the lab and will be updated by the author from time to time A i Laboratory Working Papers are produced for internal circulation and may contain information that is for example too preliminary or too detailed for formal publication It is not intended that they shouid be considered papers to which reference can be made in the literature MASSACHUSETTS INSTITUTE OF TECHNOLOGY 1982 Getting Started Table of Contents Table of Contents 1 Introduction 1 1 Lisp Machines 1 2 Timesharing 1 3 Other Computers 1 3 1 Field Engineering 1 3 2 Vision and Robotics 1 3 3 Music 1 3 4 Altos 1 4 Output Peripherals 1 5 Other Machines 1 6 Terminals 2 Networks 2 1 The ARPAnet 2 2 The Chaosnet 2 3 Services 2 3 1 TELNET SUPDUP 2 83 2 FTP 2 4 Mail 2 4 1 Processing Mail 2 4 2 Ettiquette 2 5 Mailing Lists 2 5 1 BBoards 2 6 Finger Inquire 2 7 TIPs and TACs 2 7 1 ARPAnet TAC 2 7 2 Chaosnet TIP 3 Interesting Software 3 1 Lisp 3 2 Emacs 3 2 1 TECO 3 2 2 ZWEI 3 3 SRCCOM 3 4 ATSIGN 3 5 Text Jus
19. Macsyma is an expert program for doing powerful symbolic and numerical mathmatical manipulations Macsyma was originally written in Maclisp and has been ported to the Lisp Machine At the time of this writing Macsyma is being installed on the MIT OZ computer it is also available on the Macsyma Consortiurn s ITS computer and on the MIT Multics system 7 September 1982 Getting Starte interesting Software Page 18 3 8 Electronics Design Tools DAEDELUS is a program for assisting engineers with circiut design at the chip level DAEDELUS is a program which runs on the Lisp Machine The Design Procedure Language DPL is layout language often used in conjunction with Daedelus DRAW is a program for assisting engineers with circiut design and layout at the pc board level DRAW runs on MIT AI0 with a Knight TV 3 9 FED FED is the Lisp Machine Font Editor With FED you can modify and design the character fonts which the Lisp Machine display uses 7 Sentember 1082 Getting Started Using Lisp Machines i Page 19 4 Using Lisp Machines i This chapter will briefly introduce you to the Lisp Machine but will tell you very little about actually using one Lisp Machine documentation has been published elsewhere and much more documentation in preperation For more detailed documentation good places to begin include The Lisp Machine Manual Weinreb 81 and Operating the Lisp Machine Moon 81b Lisp Machines are very powerf
20. Many programs including EXEC use this feature Recognition is Tops 20 s attempt to help you remember the arguments to a command If you type a question mark all the possible completions for the command you are typing are displayed If you type the ALTMODE key at the end of the unambiguous abbreviation of the part of the command you are typing Tops 20 will try to complete what you are typing If there are more components to the command you are typing you will be shown some guide words to suggest what the next component is Tops 20 will also try to complete unambiguous file names for you when you type ALTMODE If the system cannot figure out how to recognize your command or complete your tile name it will beep your console s bell 7 September 1982 Getiing Started Using TOPS 20 Page 44 You are encouraged to login and experiment with command recognition A good way to start is to run the TOPS20 program which will let you practice this To run the TOPS20 program just type it s name and press RETURN Online documentation for Tops 20 is available from the Help files displayed by the HELP command and the XINFO Emacs INFQ program 7 4 System Security Vanilla Tops 20 tries to provide file security and other forms of restriction protection Like most forms of computer security these features can be circumvented in various ways MIT OZ provides an atypical security environment Instead of preventing users from doing things
21. NT command and then cancel the PRINT command by typing control D instead of carriage return self s delwarn 1 2 kill f R PRINT FILE l DSK CSTACY STUFF gt 4D XXX Another useful variable to set ig the MORWARN variable Setting this variable to zero 0 will cause your More message to be terse By setting the BYERUN variable to 1 you can get a cute message or saying when you use the LOGOUT command N F Qantanhnr A000 Getting Started Using ITS Page 35 There are many customization variables in DDT Full documentation on them can be found in INFO 6 8 1 Login inits You will probably want some of the customization variables set for each of your sessions and you will probably want the same ones set each time You can do this by writing a file in your home directory which has an FN1 the same as your uname and an FN2 named LOGIN This is your login init file which is a series of DDT commands to be executed each time you log in In order to not see the DDT commands as they are executed from the file you can enclose the commands in the file inside tW off and tV on characters which control command echoing in this mode The following sample init file does these things Unless you are on a SUPDUP CRTSTY or hardwired connection it asks you if you are on a Concept 100 or VT 100 terminal and sets the terminal type correctly sets some DDT variables notifies you of incoming personal and system mail and exits I
22. Page 52 PGA Phillip G Apley 26 TEX 53 CHAOS site Sportdeath 1 GJS Gerald J Sussman 31 SCHEME 66 CHAOS site MIT MC PGS Patrick G Sobalvarro 32 EMACS 67 LISPM 25 Puma Room systat Mon 30 Aug 82 06 59 11 Up 37 21 48 8 5 Jobs Load av 1 26 1 31 1 37 Job Line Program User 9 2 EXEC Hanson 15 3 EXEC Car 17 12 BABYL Minsky 20 14 EMACS Phw 21 60 SYSTAT Gren 25 52 UNPROT Davis 26 53 TEX Pga 31 66 SCHEME Gjs 32 67 EMACS Pgs 1 26 SYSJB1 Operator 2 27 PTYCON Operator 3 30 CHARFC Operator 4 31 OPR Operator 5 32 PROTEC Operator e 7 9 Communication On Tops 20 there are three basic ways to communicate with other users comlink sends and mail Each of the three ways is best suited to a particular type of interaction 7 9 1 SENDs The SEND command is available for sending user a quick interactive the other user must be logged in message A send will interrupt whatever was printing on the receiver s console Simply type the command SEND followed by the name of the person you wish to send to SPACE or carriage return and your message Your message may be as long as you like to end it type control Z Example Gsend ley1ti Message end with Z or ALTMODE 9 If KWH typed the above command on LEVITT s console would come the message KWH TTY20 27 Ju1 82 4 86PM Is the music room free right now You can also specify a name host in the SEND command if the person you want to talk to is on i 7 September 1982
23. S This chapter will tell you hw to get started using the MIT AI10 timesharing system There are three other ITS computers in the world MIT MC a KL machine owned by the Macsyma Consortium MIT ML the Mathlab computer at the Laboratory for Computer Science and MIT DM the LCS machine where the game of ZORK was created MIT AI10 is a modified PDP 10 model KA processor with Stardust Memories a homebrew pager PDP10 PDP11 computer interfaces a 7 track tape drive and eight Calcomp disk drives MIT AI10 runs the Incompatible Timesharing System ITS developed and maintained at the MIT AI lab At the time of this writing MIT AMO is the Al Lab s ARPAnet machine is has the official host name MIT AI The system is also on the MIT Chaosnet 6 1 Logging in In order to login to ITS a user needs an identifier called a uname Unames are unique six character names which do not end in a digit People who need to access ITS from outside the building need an account with a password To log in to Al10 get to a terminal connected to the machine perhaps a Knight TV console or a Chaosnet TIP terminal and press the CALL key The first thing you probably want to do after hitting CALL is log in Logging in identifies you to the system it allows your home directory to be set and runs an login init file you may have If you are logging in from inside the building or over a network connection from another Al lab computer you will not be asked for your
24. TXT on the OZ Tops 20 system and in the file GLS JARGON gt on the AI10 system Here is a sample entry from the jargon file AUTOMAGICALLY adv Automatically but in a way which for some reason typically because it is too complicated or too ugly or perhaps even too trivial don t feel like explaining to you See MAGIC Finally remember that people in the laboratory are generally willing to answer questions and help you get staried Frequently having a more experienced user Spend a little time at the terminal with you can be more helpful than pounds of documentation Suggestions for improvements and corrections to this document or questions and requests for more heip can be sent by electronic mail to the author at the address CStacy MC or CStacy OZ Numbers in this document are decimal unless otherwise noted in the example computer user interactions in this document the user s typein is underscored It is usually obvious where a user pressed RETURN at the end of a line so no special notation is made to indicate this 7 September 1982 Getting Started Introduction Page 2 1 1 Lisp Machines The lab has a number of personal computers called Lisp Machines which were designed at the Al lab The current Lisp Machine processor is a stack oriented order code machine called a CADR With microcode to implement the Lisp primitives and a sophisticated Lisp system on top LispMs comprise the most powerful segment of our computing
25. The Device specifies which logical device the file lives on this is usually DSK the primary disk You can also specify the two letter name of another ITS ML MC DM or the Filecomputer FC The FN1 and FN2 are the names of the file most people use the FN to indicate the file type such as LISP or version such as 69 The FN2 gt and lt have special significance to ITS they refer to the newest and oldest version number of a file respectively Each user on ITS has a home directory many users have a directory whose name is the same as their uname If your home directory is not the same as your uname DDT teils you what it is when you log in The HSNAME command will also print this for you hsname chris CHRIS gt CSTACY When you use file names in DDT they are sticky This means that file manipulating commands will tend to properly default the various fields in the file name to their value the last time you issued a command Because cf this you do not need to type the entire file spec to refer to the same file or similarly named files in successive commands if you are typing a filespec and want to see what the resultant file name would be with the defaults merged in you can type an ALTMODE to get DDT to print it out Files are stored in directories To list all the files in a directory use the LISTF command You can specify to LISTF which directory to list or let it default listf mycrft AI MYCRFT FREE BLOC
26. UPDUP to another computer when you could directly connect to it instead The SUPDUP protocol Crispin 77 is a highly efficient display telnet protocol The advantage over the TELNET protocol is that SUPDUP takes advantage of the full capabilities of display terminals although it also has the ability to run printing terminals When you use the SUPDUP protocol you do not need to tell the remote host which you are connecting to what type of ierminal you have or what the terminal s capabilities are The host you are SUPDUPing from handles the actua display support for your terminal Additionally SUPDUP defines a network graphics protocol Stallman 78 which makes it easy for network hosts to draw pictures along in addition to text 2 3 2 FTP There are several sorts of File Transfer Protocols These protocols allow the transfer of files between two machines across a network Some of these protocols include various Internet File Transfer Protocols the ITS MLSLV protocol and the Lisp 7 September 1982 Geiting Started Networks Page 9 Machine Chaosnet FILE and BAND TRANSFER protocols Often when someone uses the phrase FTP they are referring to the ARPAnet internet File Transfer Protocol 2 4 Mail Electronic mail plays a very big role at our lab alot of daily communication with your coworkers both here and around the world is done via the computer How to send mail and receive depends on which computer you are using and is describe
27. achine has an advanced window system A window is a specific portion of the screen where a program can interact type cut or read input with the user The window system makes it possible for the user to make many windows of various types and helps to manage them on the screen Different programs can run in different windows or a program could use multiple windows depending on its design Often a window will take up the entire screen A useful device for interacting with windows is the mouse The mouse is a small hand sized box which can be rolled on the tabletop to control a pointing cursor on the screen On the mouse are three buttons on it which can be clicked what ihe clicks mean depends on the program reading them 4 2 booting Resetting a Lisp Machine is called booting it The most frequent kind of reset is a cold boot which completely reinitializes the machine and starts it up fresh When you are done using a Lisp Machine it is best to cold boot it for the next person When a machine has been cold booted the words COLD BOOTED appear on the screen in ihe lower right hand corner 7 September 1982 Getting Started Using Lisp Machines Page 20 When the Lisp Machine starts up it leaves you in a window called the Initial Lisp Listener This is a Lisp interpreter which runs in a window filling the entire screen 4 3 Logging in Lisp Machines are currently accessable only from the special console connected to each machine The Lisp Mac
28. ar sign The BACKNEXT character used by ITS and Emacs is l beled very differently on different terminals It usually can be simulated by typing a control underscore t 7 September 1982 Geiting Started Networks Page 7 2 Networks At the Al lab we have direct access to two computer networks the DoD ARPAnet Internet and the MIT Chaosnet A computer connected to a network is called a host The computer networks allow users of hosts to transfer data between machines in a fast and easy way For Lisp Machine users access to files on other network hosts is transparent Each host on the network has one official host name and might have additional host nicknames by which they can be referenced For example the Lisp Machine known as MIT LISPM 1 has the nicknames CADR 1 and LM1 At the time of this writing Al10 is ihe Al lab s official network machine and uses the network host name MIT Al Plans for the near future call for both Al10 and OZ to be put on the ARPAnet At that time OZ will assume the name MIT Al Here is a partial list of some computer networks from the system network tabie on MIT Al many of these networks are part of the Internet ARPAnet Chaosnet BBN RCC CMU Ethernet Cyclades Datepac DCN Comsat EDN LCSnet EPSS Intelpost Mitre Parc Ethernet 3 Satnet Srinet SU Net Telenet Transpac Tymnet and Wideband 2 1 The ARPAnet The DoD Internet connects hundreds of computers across t
29. d a little later People on the machine are referred to by their network address When you need to send electronic mail you can use the Inquire database to look up someone by their name or their network address When a message arrives for a user itis placed in a file called a mailbox Each user on a computer shouid have either a mailbox or an entry in the Inquire database saying on which machine the mailbox is located When you send a message to a non existant network address the mail system will complain to you to give you a chance to try re addressing the message and sending it again The format of network addresses will be changing slightly soon to accomodate the expanded address space of the fully operational Internet Under the present scheme a mailing address usually looks like Joe Computer where Joe is the user name of someone at the Computer site Examples Agre MIT Al DLW SCRG TENEX KDO SU AI 2 4 1 Processing Mail in order to send and read electronic mail most people employ a program called a mail reader Which mail reader you use depends on which computer you read your mail from andyour personal taste A powerful mail reader called ZMAIL exists on the Lisp Machine On the ITS and Tops 20 systems the most popular mail reader is called BABYL 2 4 2 Ettiquette l It is considered illegal to use the ARPAnet for anything which is not in direct support of Government business At the Al lab we use the network to talk to other
30. d controlling your status RUBOUT deletes the last character you typed while w rubs out the last word To flush the line you are typing use U You can redisplay the line you are typing with tR and redisplay the line on a clear screen with 4L I You can get a quick status report telling what program you are running what instruction if is executing and how loaded the entire system is by typing control T T This feature does not work if you are in Emacs since 1T is an Emacs command 7 2 2 Pausing If Tops 20 knowns the length of your terminal if you told it what kind of terminal you had or connected using the SUPDUP protocol it can pause at the end of each screenful of output if you like The command ter pause ond Will enable this feature At the end of a page Tops 20 will beep your conscle s bell and wait for you to press contol Q In the latest release of Tops 20 which at the time this document was prepared was not yet in use but should be soon there is a new way of telling the system to proceed to the next screenfull The command sequence ter pause end ter verbose Q wili make the system pause with the message More and wait for a SPACE to be typed before proceeding Any character besides a SPACE will flush the output Many users consider this behaviour a significant improvement 7 3 Recognition and HELP The user interface on Tops 20 has an interesting feature called completion and recognition
31. e TV 11 is also connected to the elevators in NE43 and the ninth floor door opener There are commands to summon the elevator and open the door A program on the PDP 10 called the Name Dragon prepares and updates a screen of information called the Free display When a TV is not in use its screen displays the Free display This display will show you who is logged in to what terminal what programs they are running and some information about the system such as the date the system version number how much core is available and how many jobs are paging There are more physical consoles than there are memory buffers The Free display tells you how many are functional and how many are in use The Free display also bias which Lisp Machines are in use and the location of free ones Other things displayed include birthday notices an amusing picture and the time of day the Free display was updated When a TV is being used the bottom line on the screen contains an interesting status report called a wholine The wholine shows the user name job name date and time status running paging etc the system fair share and other interesting data 7 27 82 4 13 28 3 CSTACY E CSTACY ECHOIN 1 32 0 12 07 4 63 94K The ESCAPE key different from ALTMODE is used to send special commands to the PDP 11 controlling the TV display Commands are single letters which may be preceeded by numeric arguments The commands are nat echoed 7 Septernber 198
32. e security can be found under the HELP topics Protection and Security 7 September 1982 Getting Started Using TOPS 20 bage46 7 5 Manipulating Forks A user and all of his programs run in a single Tops 20 job Each of the programs in a job usually runs in its own fork The EXEC manages these job forks for you and allows you to switch between them To start a program in a fork simply type its name Example Gemacs The command INFO FORK prints out the names of all your forks and some information about their state You can abbreviate this to FO Here is an example with an currently selected MM fork and an EMACS fork infORMATION ABOUT foRK STATUS f EMACS 1 Kopt HALT at 61364 00 00 16 6 MM 2 tC from IO WAIT at 36410 00 00 00 1 When you exit most programs their forks stays around until you explicitly flush them The RESET command gets rid of a fork Greset emacs Typing RESET with no argument gets rid of the currently selected fork Sometimes a RESET with no argumnet doesnt want to get rid of the current forl Giving the argument to RESET command will always get rid of the current fork Giving the argument to a RESET gets rid of all your forks i fo FMACS 1 Kept HALT at 61364 00 00 16 6 MM 2 tC from IO WAIT at 36410 00 00 00 1 SEND 3 t from IO WAIT at 35410 00 00 00 1 gt CFTP 4 tC from I WAIT at 35410 00 00 00 1 rese I 81 fo To create a new fork which contain
33. ed PDP 10 KA computer which runs the powerful Incompatible Timesharing System ITS Along with the now demolished PDP 6 computer this old machine served as the primary computational resource for the first part of our history Because of its old age Al10 is not a very reliable computer and most people do not store important files on it MIT OZ is a PDP 10 KL model B computer a PDP 20 Acquired in June of 1982 this machine is intended to serve along side and eventually replace the services of the KA OZ runs an enhanced version of the Tops 20 operating system Tops 20 is sometimes called Twenex 1 3 Other Computers Various groups in the laboratory have facilities useful for doing special kinds of computing Details about these facilities are very dynamic and beyond the scope of this document To get specific details or to arrange to use this special equipment contact someone from the appropriate group 1 3 1 Field Engineering The Field Engineering project has two VAX computers an 11 780 called HTVAX and an 11 750 called HTJR HTVAX runs the Unix operating system and HTJR runs DEC s VMS These machines are available to members of the group for their work in expert systems which debug complex computer hardware Various faults will be introduced into HTJR s hardware and programs on HTVAX will diagnose the failures 1 3 2 Vision and Robotics The Vision and Robotics groups at the Al lab have developed and obtained some interesting pe
34. eloped at Xerox Some parts of the MIT Eihernets use Chaos software protocols instead of the Ethernet protocols There are many hosts on the Chaosnet A few of them include Al Alcator ARCMac Bypass CCC CIPG Cog Sci CSG DSPG Eecs Franky Mouse Fusion HTVAX JCF LNS VAX Math MC ML Multics OZ PFC VAX Plasma RTS SIPB Speech and XX 2 3 Services The computer networks provide three basic services Remote Access Telnet File Transfer FTP and electronic Mail Many more network protocols exist to do both low level and user level things For example upon booting Lisp Machines set their time of day clock by polling various other computers on the Chaos network for the time of day Another example of a useful protocol is the SEND protocol which allows a user on one machine to send an interactive message to someone on another machine You can design and implement your own protocols for your programs and conduct interesting experiments if you like Here is a brief description of the frequently used common services 2 3 1 TELNET SUPDUP The TELNET and SUPDUP services allow a user on one system to remotely cennect through the network to another system and use it as though they were directly connected his is mostly useful for briefly visiting a machine other than the one you are using or for reaching a machine who you cannot directly dial up It is usually wasteful and inefficient to use a computer exclusively to TELNET or S
35. enting Display Editor Al Memo 519 Artificial Intelligence Laboratory Massachusettes Institute of Technology March 1981 Wechsler 82 Wechsler Zmacs User s Guide Symbolics Inc 1982 7 September 1982 Getting Started References Page 57 Weinreb 81 Weinreb amp Moon Lisp Machine Manual Artificial Intelligence Laboratory Massachusettes Institute of Technology 1981 Xerox 79 Alto User s Handbook 1979 7 September 1982 Getting Started Index Page 58 Index AMO 25 Alto 4 ARPAnet 7 Associated machine 19 20 ATSIGN 17 BABYL 16 Bboards 11 Bogosity 42 Bug reporting 10 Bugs 10 BUILD 50 CADR 2 Chaosnet 7 13 Chaosnet TIP 13 Chroma 4 Cold boot 19 Conilink 38 53 Completion 43 Convolver 4 CRTSTY 33 DAEDELUS 18 DOVER 5 32 49 DPL 18 DRAW 18 Emacs 16 EXEC 42 54 Expunge 48 Fair share 28 FED 18 FILE protocol 8 Filecomputer 2 Fork 46 FPS 2 FTP 8 HELP 43 Host 7 INFO 16 27 35 44 Inquire 37 51 Internet 7 ISPELL 17 ITS 3 5 25 Job tree 28 Jobs ITS 28 Jobs Twenex 46 Junk 32 KTV 5 KTVs 22 7 September 1982 Getting Started Index Page 59 LISP 2 15 19 Lisp Machine 2 19 Logical names 48 Luser 27 Macsyma 5 17 25 Magic 1 Mail 9 MIT TAC 12 Mouse 19 NCP 13 Network address 9 Networks 7 Nil 15 PCL 54 Press 4 49 Protector 44 R 17 Recognition 43 Scheme 15 SCRIBE 17 SPELL 17 SRCCOM 17 SUPDUP 8 13 T 15 TAC 12 TCP 13
36. erning Emacs Zwei including the Emacs Manual Stallman 81a and Stallman 81b Wechsler 82 Ciccarelli 78 Stallman 81c The original Emacs was written primarily by Richard Stallman RMSQAI under the ITS operating System With the advent of the Lisp Machines Dan Weinreb wrote an editing system called ZWEI and implemented the Zmacs editor in it The word EMACS probably originally stood for Editing Macros Another popular theory says that itis a recusive ancronym meaning Emacs Makes All Computing Simple ZWEI stands for Zwei Was Eine Initially Eine was an early version of the LispM editor Eine Is Not Emacs 7 September 1982 Getting Started interesting Software i Page 16 There is also an Ersatz Emacs editor on the VAX timesharing machine Emacs and Zwei can serve as a base for advanced friendly programs especially for applications involving text processing if some sort Here are a few popular programs which are based on Emacs 1 INFO called XINFO on Tops 20 allows you to examine tree structured online documentation files There is alot of useful information in INFO you should check it out on the timesharing machine you use 2 DIRED is a directory editor It allows you to easily examine and modify your directory changing file attributes deleting files etc from inside the editor 3 BABYL is a program for reading and sending electronic mail BABYL will reformat the memo headers of incoming messages to look
37. f KWH typed the above command on LEVITT s console would come the message MESSAGE FROM KWH at MIT AI 4 56PM Is the music room free right now A send will interrupt whatever was printing on the receiver s console If you were not in DDT at the time you received a send DDT will repeat the message when you exit to make sure you saw it There are customization varibles to control this repeating You can also specify a uname host in the SEND command if the person you want to talk to is on another machine If the person you want to send to is on a non ITS machine on the ARPAnet you should use QSEND in lieu of SEND QSEND is cross between SEND and MAIL and works with many computers on the net If you do not want to receive sends from other users you can use the GAG command prevents incoming sends and gag 1 re enables them It is usually considered anti social to gag yourself 6 10 2 Comlinks Comlinks are the most interactive way of communicating with another user on 1TS When two or more users are in a comlink they will each everything which is being displayed on any of the consoles Although there is no limit to the number of people in a comlink due to the psychology of human conversation comlinks usually work best when only two people are linked at once more people in a comlink tends to be confusing 7 September 1982 Getting Started Using ITS i Page 39 Comlinks are controlled by commands beginning with the s
38. f includes messages about requests for information job offers and housing searches To send mail to a BBoard you simply address your message to a specially named address just like a mailing list Here is a description of some useful BBoards You can mail to these addresses on MIT OZ BBOARD All the people on MIT network computers can read these messages MAC All of the Al lab and LCS read these system messages MIT All the people on network machines at MIT read these system messages ITS The users on the four ITS machines see a message sent to ITS at any single machine Al The users on the Al10 and OZ machines see a message sent here OZ Messages to the MIT OZ Tops 20 system users 2 6 Finger inquire The Finger protocol is used to get a list of what people are using a computer on the network Inquire is the generic name of a program which manages an informal database of who our computer users are The Inquire databases have such information as your user id full name network address what user name on which computer your electronic mail should go to your office telephone number and other useful things In addition to being used by the mail programs Inquire provides everyone on the machine with an instant directory of people via the WHOIS and FINGER programs There are several Inquire databases some of which are commonly shared by more than one machine Which databases you are registered in depends on w
39. he current job to let you know which one you picked The short form of the JOB command is J ALTMODE j Once you have selected a job and made it be the current job here are some things you can do with it The CONTINUE command will proceed the job and give it control of the console The PROCEED command will proceed the job without contro of the console If the job is named FOO and it wants to type something on your console it will make DDT say sos 7 September 1982 Getting Started Using ITS Page 30 FOO WANTS THE TTY Making FOO the current job and typing the CONTINUE command to DDT at that point would then give FOO the TTY The short form of the PROCEED command is control p iP The KILL command gets rid of the current job When you attempt to create a job with the same name as an existing job of yours DDT will offer to clobber the existing job and start a fresh one You should type a SPACE to say yes and clobber the job or press RUBOUT to not kill the existing job There are customization varibles to change the behaviour of this feature The MASSACRE command KILLs ait ef the jobs in your HACTRN 7 September 1982 Getting Started Using ITS Page 31 6 6 Files On ITS users store data in files To access a file you must know its name File names consist of several component fields The syntax of a file name looks like Device Directory FN1 FN2 Each of the fields can be up to six characters long
40. he host will echo one more so it will look like 9e e i l You can change what the TAC s command intercept character is by using the command 81 number i Where number is the decimal number of the ascii character ta make be the TAC command intercept character A poputar value is 126 which is a tilde another is 36 control uparrow To reset the intercept character to an atsign you can type 8i esc The ARPAnet Internet is stilt undergoing conversion to the new Internet protacals At the time of this writing the TAC is normally in NCP made when you first connect to it When a TAG tries to open a connection for you it will mention which protocol it is trying to use These twa commands can be 4the older protocol is known as NCP 7 September 1982 Getting Started Networks Page 13 issued if you want to change which protocol the TAC is going to use Gprotocol Tcp and Gprotocol Ncp To connect to a host on the ARPAnet use the command Gopen net port imp The network number is optional if you want to connect to a host on the ARPAnet The ARPAnet is network 10 incidentally The TAC will then say TRYING and presently you will be hopefully connected and speaking to the system you requested Here are the nunmbers of some common ARPAnet hosts MIT Al 2 6 MIT MC 3 44 MIT ML 3 6 MIT DM 1 6 MIT XX 0 44 SU AI 0 11 SU SCORE 3 11 SRI KL 1 2 Finally to disconnect from the host you are usi
41. he world together over in a large catenet of smaller packet swictched networks The ARPAnet is the original component of the Internet The ARPAnet is used primarily by the Government agencies other organizations sponsored by the Advanced Research Projects Agency The ARPAnet is managed by the Defense Communications Agency DCA The ARPAnet provides us with a relatively high speed digital link to many important research centers such as Stanford University Carnegie Melon Universty Berkeley Yale SRI Xerox PARC and BBN Additional information about the ARPAnet can be found in the newtwork resource handbooks and protocol documentation from the Network Information Center NIC at SRI International NIC 82a NIC 82b The NIC maintains an online respository of Request For Comments RFCs and Internet Experiment Notes IENs and online directories of computers software and people on the network 2 2 The Chaosnet The Chaosnet is a high speed packet switching coaxial network designed at the Al lab The Chaosnet employs its native Chaos protocol described in Moon 81a The Chaosnet connects many computers around MIT and elsewhere This includes all the Lisp Machines the Al Lab s and many of LCS s timesharing machines the EE Department the Plasma Fusion group and more 7 September 1982 Getting Started Networks Page 8 Also connected to the Chaosnet are gateways onto MIT Ethernets Ethernet is another higher speed coaxial network dev
42. hich computers you use the most it is not a bad idea to have an entry in each of them 7 September 1982 Getting Started Networks Page 12 2 7 TIPS and TACS In addition to any direct dialup lines which a host might have there are special hosts know as TIPS and TACs The name TIP comes from the early days of the ARPAnet and stands for Terminal Interface Processor On the ARPanet Internet these minicomputers are now called FACs Both TIPs and TACs serve the same purpose A TIP can use the TELNET or SUPDUP protocols te dynamically connect a terminal to some other computer on whatever network the TIP is on For example if you are at home and wish to use same ARPAnet host say MIT Al or Stanford s SU SCORE you could call the locat ARPAnet TIP and have it connect your terminal to that system if you needed to use the HTVAX which is only on the Chaosnet you could call a Chaosnet TIP and connect to it i 2 7 1 ARPAnet TAG The ARPAnet FACs are useful for connecting to machines which are directly on the ARPAnet Internet To use the FAC obtain the dialup number from your supervisor and connect your terminal to the phone To begin using a 300 baud line type control Q To begin using a 1200 baud line type QR RETURN The TAC should respond like MIT TAC 424 61 Commands to the TAC are preceeded by an atsign While you are using the TAC whenever To send an atsign through you need to type two of them and t
43. hines themselves are located in a computer room many of them are located in a corral on the ninth floor in Tech Square LispM consoles are located in offices throughout the lab A LispM console consists of a high resolution video monitor and a keyboard You will probably notice that the keyboard has alot of keys on it One useful key is labeled HELP it can be pressed to get helpful information Also attached to the console is a mouse Mice are purported to work best when rolled around on the surface of a Lisp Machine Manual Before you can login to a Lisp Machine you need to locate one It would be tiring to walk around to each LispM console to see if someone was logged into it A quicker way of finding a machine is to either look on the Free Display of a Knight TV or ask someone on the nearest Lisp Machine to generate a list of free machines The LispM command to get a list of which Lisp Machines are in use and which are free is TERMINAL 1F That is press the TERMINAL ey followed by the number 1 and the letter F Once you have found a Lisp Machine be sure that it is really not in use A Lisp Machine which is not in use has mostly likely been completely reset cold booting On the screen will be a heratd telling what the name or number of the Lisp Machine is some information abcut what version of Lisp Machine software it is running and which machine the LispM is associated with The user interface to the Lisp Machine does not include a com
44. hird floor computer room near the VLSI lounge This electrostatic printer is useful for producing mediutn quality wallpaper in bright ch ery VLSI patterns It is controlled by a Lisp Machine and will soon be connected directly to 7 Septernber 1982 Gelting Started Introduction Page5 the Chaosnet 1 5 Other Machines On the ninth floor in building NE43 the Al Lab shares space with the Laboratory for Computer Science LCS LCS has several machines which are on the ARPAnet MIT XX is a Tops 20 machine with a hardware configuration similar to that of MIT OZ LCS also has two ITS systems running on KA 10 processors MIT DM and MIT ML which is used primarily by the Clinical Decision Making group The Macsyma Consortium has a KL 10 processor running ITS which is operated by the Mathlab group at LCS for Consortium members this machine is called MIT MC LCS recently acquired many VAX 11 750 computers configured as single user machines The Ethernet IFS is operated by LCS this filecomputer system is used primarily by Altos 1 6 Terminals There are several kinds of terminals you can use to access many of the computers in the laboratory Which kind of terminal you use depends on which machine you want access lo and what is convenient for you Scattered throughout the lab are conventional terminals such as Concept 100s and Ann Arbos These are usually attached to a Chaosnet TIP decribed later when we talk about netw
45. inals The TERMINAL command is used to tell Tops 20 what sort of terminal you are on Example Oterminal c100 Giving the command terminal to the EXEC will get you a list the terminals and options which Tops 20 understands 7 8 Inquire To make an Inquire entry on OZ run the INQUIR program The WHOIS command will print on your terminal all the information associated with a user in the OZ INQUIR database Example i whois kwh KWH Ken Haase Last logout Wed 24 Mar 82 01 23 from TTY212 Ken Hacking amateur systems for Minsky Music Work NE43 352 617 253 1728 Home 4 Ames Street KWH has no new mail No plan whois danny T DANNY Danny Hillis Last logout Wed 24 Mar 82 00 23 from TTY216 Danny Hack ng connection machine CM Work NE43 711 617 253 6765 Home 111 Ivy St Brookline MA DANNY has new mail from KWH at Wed 24 Mar 82 00 20 last read Tue 23 Mar 82 20 28 No plan Numerous commands and programs exist to obtain system status reports FINGER and SYSTAT being the most commonly used Qf inger User Name Job Subsys Idle TTY Console Location HANSON Christopher P Hanson 9 EXEC 2 825 Hanson x5848 CARL Carl Hewitt 15 EXEC 3 813 Hewitt x5873 MINSKY Marvin Minsky 17 BABYL 12 1200b dialup PHM Patrick H Winston 20 EMACS 14 1200b dialup GREN lan G Mackey 21 FINGER 50 NE437A Playroom DAVIS Randy Davis 25 UNPROTECT 52 HTJR 819 Davis 7 September 1982 Getting Started Using TOPS 20
46. is to beep their bell by typing control G If you are in a comlink and wish to type something at the program such as your HACTRN which is running underneath the link you can toggle input mode on and off with the command BACKNEXT I It is also possible to type at the programming running on the other person s console this is called slaving because it allows you to take control of someone else s terminal The command to toggle slave mode is BACKNEXT E Sometimes you may not wish to be interrupted with an incoming comlink By putting your console into query mode you can restr ct who you will link with If you are in query mode and someone tries to link with you you will see the message LINK FROM KMP QUERYING You can answer with BACKNEXT Y for yes to allow the comlink or BACKNEXT N to disconnect the person If the person gets bored of waiting for your response they can use the backnext N command tounlink To put your terminal in comlink query mode type 7 September 1982 Getting Started Using ITS Page 40 tciyp query There are times when you will want to completely disallow comlinks and there is no point in even being asked If you put your terminal into refuse mode all incoming comlinks will be rejected with the message REFUSED on the console of the person trying to link To get into refuse mode type the command itctyp refuse To get out of query or refuse mode use the command tctyp acce
47. le An uncoming rewrite of the Inquire database system will change the naming c nvention so that each person has a unique short username which is not necessarily the same as the person s directory name To log into OZ get to a terminal connected to the machine perh ps hardwired terminal or a Chaosnet TIP terminal and type control C The system should respond by identifying itself Now type the login command Glogin username password If you like you may actually omit th command name and simply type your usern me and password To logout type the word LOGOUT and press RETURN 7 2 Commands When you login to Tops 20 you are typing at a program called the EXEC The EXEC understands many commands for such things as managing your file directories getting information about the system starting programs and talking to cther users on the machine To type a command simply type its name and any parameters for the command and press RETURN The EXEC usually prompts you with an atsign when it is ready to receive a command Some comands put you in modes in which only certain subcommands ar valid in that case your prompt will be a double atsign 84 directory whose immediate superior in the file system hierarchy is the ROOT DIRECTORY 7 S ptember 1982 Getting Started Using TOPS 26 Page 43 7 2 1 Control Characters Tops 20 programs generally understand the following control characters for editing your typein an
48. lities allowing them to bypass any system security When Protector is released for general use these accounts will be modified appropriately 7 4 1 File Security Most users at the Al lab feel no need to protect their files from other lab members There is generally no information stored online which is not public to at least the lab community and lab members are encouraged to be responsible when using the machine and careful with other people s files i Tops 20 allows users to make their files and directories inaccessable to other users You can 9A remedial Protector deamon is operational now but is very limited in the functions it provides 7 September 1982 Getting Started l Using TOPS 20 i Page 45 restrict particular kinds of access read write delete etc to a file or directory from three individual sets of users i The default file system protection on OZ allows all users to access eath others files User s are encouraged to stick to the default protection which is the simplist and friendliest thing to do When setting the restrictions on a file or directory you specify which access will be allowed to three types of users the owners the people in groups with you and all the rest of the users Protection for files is specified as a mask of three two digit octal numbers Each number in the protection code corrosponds to one of the three categories Protection for directories is specified as four numbers since di
49. lly the name of some disk structure or a logical name A disk structure may refer to either a single disk pack or to a set of packs For example PS public structure the primary disk structure on the machine consists of several mounted disk packs Typing the command help structures Will provide you with information about what structures are currently mounted on the system and a brief description of what they are for The Directory identifies who owns the file The Name component is the field which most uniquely identifies a file The Name component of a filename can be pretty long The Extension component is the field which dALTMODEribes what sort of data is stored in the file this is the file type Extensfons are usually three or four characters Some common extensions include TXT text LISP Lisp source and EXE executable binary image The generation is the version number of a file When a new version of the file is written out the generation number is incremented Here are some examples of legal file names 7 September 1982 Getting Started Using TOPS 20 i Page 48 PS lt AGRE gt SCDPCM QFASL PS lt CSTACY gt MAIL TXT SS lt EMACS gt MODLIN TEC 7 6 1 Directories Files are stored in directories Directories are per structure having a directory on one structure does not imply haying one on whatever other structurea are mounted In order to log in a user on Tops 20 must have a directory which has
50. mand interpreter Instead you type Lisp expressions for evaluation and for side effects To login use the login form which requires a single argument your user name If you do not wish to use the associatd timesharing machine yous should include second argument the name of the system where your files can be found login cstacy mc When you are done using the machine the usual practice is to cold boot it This is done by holding down both the left and right CONTROL and META keys while striking the RUBOUT key 4 4 Editing and Compiling To begin editing your programs you need to enter the editor This is done with the edit form which requires no arguments Edit wilt put you into Zmacs an editor which is very much like Emacs edit If you Know how to use Emacs you should have no trouble the simple commands alf work the same When you want to exit back to Lisp use the controf Z z command 7 September 1982 l Getting Started Using Lisp Machines Page 21 One way to compile some Lisp code into the environment is to mark off a region in the editor and use the M X Compile Region command There are many many more commands for interacting with Lisp from the editor 1 4 5 Communication The Lisp Machine is on the Chaosnet so LispM users can send messages to each other and to people on timesharing machines To send a message to someone use the qsend form Qsend requires as its argument a string containing the name
51. me or initials before you start typing so that it is easy to inedntify who is saying what The way to yell shut up or otherwise get someone s immediate attention in a comlink is to beep their bell by typing control G 7 September 1982 Getling Started Using TOPS 20 Page 54 7 9 3 Mail Tops 20 has several programs for Sending and receiving mail These programs do not actually perforin the sending of mail this is handled by a deamon called XMAILER Probably the best way to process your mail is with the BABYL program The SYSMSG and FORUM programs wit examine the system bboards and offer to print the messages in it on your terminal In order to receive mail on OZ you rieed to have 4 file named MAIL TXT in your directory This file is created automatically whenever a directory is created so unless you have somehow deleted it manually you should not need to worry about if Uriik some Tops 20 sites you only need to alter your Inquire entry with INQUIR to have your mail forwarded to another address 7 10 Customization When you issue the LOGIN command the file LOGIN CMD in your directory is run if it exists This file should contain a series of EXEC commands to set up your session Here is a sample login init file which sets up some terminal characteristics and starts up the bboard reading programs term page term wrap sysmsg forum take Figure 7 2 Sample EXEC init file If you have many subdirectories riother u
52. mine the system bboards and offer to print the messages in it on your terminal The GMSGS program is similar but puts the messages into your mail file instead 6 11 Using Network Programs The FTP program for transferring files from the ARPAnet Internet is called FTP The TELNET program is called TELNET and the SUPDUP program is called SUPDUP These programs are mostly self documenting I 7 September 1982 Getting Started Using TOPS 20 Page 42 7 Using TOPS 20 This chapter will tell you how to get started using the MIT OZ timesharing machine OZ consists of a DEC 2060T KL model B processor two megawords of 36 bit MF 20 memory eight 177MB RPO6 disk drives two TU 77 tape units and various network interfaces including ARPAnet and Chaosnet MIT OZ runs an enhanced version of the DEC TOPS 20AN operating system which is maintained by the MIT computing community Tops 20 is also sometimes called Tops 20 7 1 Logging in o In order to login to Tops 20 a user needs a loginable directory on the system s primary disk structure the PS device Currently Tops 20 is set up so that a person s username is the fume as the name of their login directory This means that if you do not have a toplevel dir ctory your username is probably cumbersome string Most users have toplevel directories so this problem is often avoided However as the number of people in login subdirectories grows this username convention b c mes uncomfortab
53. n about ITS and the programs on it can be found with the INFO program INFO is self documenting and includes a built in tutorial If you are really having trouble you can request a system hacker to come and help you by typing the LUSER command lusen Help has been sent for please walt KILL LUSER will tell you if it cannot find anyone to ask for help 7 September 1982 Getting Started Using ITS Page 28 6 3 1 System Load The load on the machine is measured as the fair share Considering the number of jobs in the system and the amount of system overhead the fair share is the percentage of the machine s computrons that each of the jobs which wants to run should get The larger the fair shiare s value the less loaded the machine is You can see what the current fair share is by looking on your wholine or by entering the SSTATUS command The LOADP program can also be used to print some system toad information LOADP tells how many users are on the machine how idle they seem to be and how many network ports STYs are free 6 4 System Security ITS does not have any security to prevent users from doing things As result it is incumibant n ITS users to take care not to damage other people s files All users may freely access any fil they choose and can run programs which might be considered privileged on Some systems 6 5 Jobs As mentioned before job is the entity in which programs run A job in the System is U
54. nd you would be left inside a Lisp interpreter ready to start typing in Lisp s expressions You could temporarily exit the LISP job and get back to DDT by typing the CALL key Must users have more than one job in their job tree typically there is an EMACS and some other job perhaps a Lisp interpreter DOT thinks of your inferior jobs as belonging in a ring where one of the jobs is the currently selected job You can give commands to switch between jobs and make which ever one you choose be the current job To iist all your jobs and see which one is the current job use the LISTJ command An asterisk is printed next to the current job slistj LISP P 2 EMACS P 33 In the above example to the right of the jname is a single letter indicating the state of the job followed by the job s internal number in the system The P state means proceedable you can use the CONTINUE command on this job to resume t Other common states include R for running the job is running but doesnt have control of the console and W for waiting meaning that the job was running but is stopped because it needs back control of the console to do further work To make a job named FOO be the current job type the JOB command job foo Instead of explicitly saying what job to make current you can rotate through the ring of jobs by omitting the argument to the JOB command In this case DDT will print out Fooss where FOO is the jname of t
55. ng type the command 0Close TIP commands can be abbreviated to their first letter 2 7 2 Chaosnet TIP The Chaosnet TIPs are PDP 11 based terminal concentrators connected to the Chaosnet We currently have installed two Chaos TIPs named NE439A and NE433A on the ninth and third floors respectively Chaos TIPs r n an operating system called MINITS which understands a few simple commands NE433A is connected to the local terminals such as Concept 108s and AnnArbors inside the lab NE439A is connected to Vadic 1200 baud dial up modems as well as local terminals Chaos TIP commands begin with a control backslash To send a control backslash character to the host you are using you must type the character twice Alter the t you might type a numeric argument and then a single letter command The numeric argument should be either the octal Chaosnet address or a host number to connect to Here is a summary of the single letter commands 7 September 1982 Getting Started Inter sting Software Rage 14 Connect using the SUPDUP protocol Connect using the TELNET protocol Connect using the Finger protocol Disconnect from the currently selected host List available hoste and their numbers and these commands oC 1 A Ag Some popular host numbers include 0 MIT MC 1 MIT AH0 4 MIT XX 14 MIT OZ Figure 2 1 Chaos TIP commands 7 Sebtember 1982 Getting Started interesting Software Page 15 3 Interesting Software Thi
56. nicer can keep keyword tags on messages and has a powerful Survey Mode for scanning through large mailboxes 3 2 1 TECO The original PDP 10 Emacs is implemented in ITS TECO an amazingly powerful and amazinlgy obscure language which most closeiy resembles line noise Here is some sample TECO from an Emacs init file this code redefines what functions certain key commands will invoke when typed in this user s editing enviroriment QtRt q tRt utRt Ju tRT Switch RUBOUT and C RUBOUT q tRWu x tttK Make C X C K do like C W l Luckily you can do many customizations without learning TECO and you can usually find a TECO wizard around to help you do more fancy things and write new editing commands 3 2 2 ZWEI With the larger address space available in Lisp Machines the ZWEI editor Zmacs was able to be written in Lisp Here is some Lisp code from a ZMACS init file which does the same thing as the TECO code did in the PDP 10 Emacs above zwei login eval set comtab return undo I standard control x comtab control K com kill region zwei login eval set comtab return undo EN 8ome former MIT students developed and marketed an Ersatz Emacs editor for microcomputers called MINCE Mince Is Not Complete Emacs 7 September 1982 Getting Started Interesting Software Page 17 standard comtab control rubout com rubout rubout com tab hacking rubout 3 3 SRCCOM is The SRC
57. niquely identified by its two names its uname which identifies its owner and its jname When dealing with DDT to manipulate your own jobs me uname which is the same as your uhame is usually not mentioned The thing that DDT is good at is manipulating jobs A user can have Several jobs extant concurrently arranged in a tree which with a HACTRN containing DDT at the apex More than one job may be running at a time but only one job has control of the console to type out and read typein from With the understanding that DDT is the name of the program and HACTRN is the riame of th job in which it runs we will use the terms interchangably hereaft r to refer to your toplevel jab Initially your DDT has control of the corisole When you start up another job DDT passes the console to the new job called the inferior job because of its place in the tree relative to BBT HACTRN a AM XEM EMACS X LISP Control of the console can return to DDT if th program decides to interrupt its superior H GTRN or if you press the CALL key to force the interrupt yourself To resume a job which has been stopped with the GALL key type th CONTINUE command The short form of continue is P ALTMODE P 7 September 1982 Getting Started UsingiTS Page 29 To start a job simply type its name as though it were a long form comrnand For example to start up a LISP interpreter type lisp LISP 2122 Alloc _ if you typed the above comma
58. ords 50 7 7 Terminal Support 51 7 8 Inquire 51 7 9 Communication 52 7 9 1 SENDs 52 7 9 2 Comlinks 53 7 9 3 Mail 54 7 10 Customization 54 7 10 1 PCL 54 7 11 Using Network Programs 54 8 References 55 Index 58 7 September 1982 Getting Started Figure 2 1 Figure 5 1 Figure 5 2 Figure 6 1 Figure 6 2 Figure 7 1 Figure 7 2 List of Figures List of Figures Chaos TIP commands The Name Dragon s Free Display Knight TV commands ITS directory listing Sample DDT init Sample User Groups Table Sample EXEC init file Page iv 14 23 24 31 54 7 September 1982 Getiing Started Introduction Page 1 1 Introduction This document is written to help you get acquainted with the computational facilities at our laboratory and to provide enough introductory information to get you started using them Although the use of various computer systems is described in this document it is intended as an introductory guide not a complete reference manual If you would like a copy of a reference manual or an Al Laboratory Memo or Working Paper you should visit the Al Publications office Alot of unique jargon is used by people at the Al Lab As a matter of historical interest copies of an online file containing a jargon dictionary are kept on the timesharing machines at the lab You would probably find it useful and entertaining to take a look at this file A copy exists in the file PSXGLS JARGON
59. orks These are useful for accessing timesahring machines on the Chaosnet like Al10 and OZ Lisp Machines on the other hand require you to use a special console which is wired directly to them Consoles connected to the Knight TV system allow you to connect to the AI10 Most terminals have special shift keys on them called Control and Meta Typing control A means holding down the CONTROL key while simulataneously pressing the letter A One way to refer to the character control A is to write a In many programs control A actually prints that way when you type it Sometimes you will find mention of keys which don t seem to be on your terminal s keyboard Sometimes the key is simply labeled differently while in other cases you must type to simulate the missing key For example the RETURN key is almost always labeled RETURN By contrast the CALL key does not 3L abeled Contro or ctri On an Ann Arbor Ambassador terminal Meta is labeled Pause while the Meta keys are _ completely unlabeled on a Concept 100 7 September 1982 Getting Started Introduction Page 5 appear on many conventicnal terminals When using an ITS computer via a conventional terminal you can type control Z to simulate CALL The ALTMODE or ALT key is sometimes labeled ESC or ESCAPE on conventional terminals On terminals which don t have enough graphics capability to print the altmode character altmode is usually displayed as a doll
60. orms are convenient to type There are many short form commands used for debugging assembly code you will probably never need to type them We mention such commands here to ease your confusion because you are likely to someday inadvertantly type one by accident For example if you type a slash you will usually make DDT type the contents of some memory location 6 2 1 Control Characters DDT understands several control characters for editing your input and interrupting the system The CALL key or tZ is used at almost any time to get the attention of ITS interrupt the running job and return you to DDT Control G is an interrupt similar to CALL but it is more drastic and is not guaranteed to leave things in a consistant state Coritrol S is used to stop the output of a DDT command The RUBOUT key deletes the last character you typed Control D deletes the current line being typed Control L clears and refreshes the screen retyping the current line 6 2 2 More When you are using ITS an a display terminal the system will pause at the end of each page of output and wait for you to tell it to continue This ensures that you have a chance to read the screem before it is rewritten When it pauses it will type More and wait for you to press either SPACE to continue or RuBOUT to flush the output If you type a character other than RUBOUT or SPACE it will be treated as a RUBOUT 6 3 INFO Extensive online documentatio
61. ox donated a number of these machines to Universities The Alto is the predecesor of such Xerox computers as the Dolphin Altos re usually programmed in the Mesa language or in Smalltalk At th AI lab Altos are primarily used to run the Alto Draw program An Alto can be used to play various graphics ofiented qames such as Pinball Star Trek Asteroids and Space Invaders Alto documentation and documentation for the DRAW program can be found in the Alto User s Handbook Xerox 79 Files can be transferred over the Ethernet using the Internet Trivial File Transfer Protocol See ihe documentation on FTP in Xerox 79 1 4 Output Peripherals There are several output devices for network users in Tech Squar There are two Xerox laser printers which can be used to print medium to high quality output an electrostatc sheet printer and Tektronix screen copier The Dover is a high speed high quality laser printer located in the ninth floor computer room lt is driven by Xerox Aito computer running a file spooler called Spruce Files often go through another spooler on the MIT MC timesharing Computer before they get to the Alto Files sent to the Dover are in PRESS format The Xerox Graphics Printer XGP is the venerable ancestor of the Dover The XGP is controlled by a PDP 11 and is spooled to by a program which runs on MIT AI0 The fonts available for the XGP are decribed in XGP A Versatek printer is located in the t
62. password When connecting to the machine from outside the building over a dialup or network you will need to type a password to prove who you are To log into ITS type the LOGIN command AI ITS 1268 DDT 1388 TTY 62 8 Lusers Fair share 69 login uname 0K All programs which run on ITS run in jobs Jobs have names up to six characters long When you first press the CALL key and get the attention of ITS ITS creates a job called HACTRN for you and starts up a copy of DDT in it When started DDT says hello with its version number the ITS version number your tty line number and how many users are on the machine and how loaded it is Finally DDT will print its prompt an asterisk to let you know it is ready for commands T M Scustom MOS memory designed by Howard Canon HIC MIT MC The Stardust is often referred to as the HICMEM 7 September 1982 Getting Started Using ITS Page26 6 1 1 Logging Out When you are done using ITS you should type the LOGOUT command logout AI ITS 1268 Console 37 Free 09 32 21 The logout command will destroy any jobs you were running including your HACTRN at which point you will be logged out If you are on a dialup line or a net port and are disconnected without first logging out your HACTRN and other jobs will become detached instead of destroyed When you next login again DDT will offer to re attach them for you If you answer no to this offer yo
63. pecial character called backnext This character actually exists only on Knight TV keyboards but it may be simulated by typing control underscore or MACRO Note on certain ascii terminals with non standard keyborad encoding the backnext character is obtained by typing control questionmark et To establish a comlink with another user type the command BACKNEXT Cuname This will cause ITS to print OK and link you together If the person is in another comlink with someone already ITS will ask you y or n if you want to break in and have a multi way comlink To end a comlink to another user type the command BACKNEXT N You do not have to be in DDT to use the comlink feature of ITS Comlinks work on top of any program While you are in a comlink none of your typein is seen by DDT or whatever other program you were running when you entered the refuse There is an etiquette for talking to people in comlinks Because a comlink is a pretty violent interruption you should usually ask someone with a send for permission to enter a comlink Each person in the link takes turns typing When you are done saying something type a blank line to let the other person Know you are finished i If you are in a multi way comlink you should sign your name or initials before you start typing so that it is easy to inedntify who is saying what The way to yell shut up or otherwise get someone s immediate attention in a comlink
64. pt There are additional comlink commands described in the file INFO ITSTTY gt 6 10 3 TALK If you want to link to someone who is on another ITS machine you can use the TALK program The program is run by typing talk uname8host To exit TALK terminating the conversation the user who initiated TALK must type 1C This method of comlinking is less versatile than the backnext commands and only works across ITS machines not locally Another useful comlink program is UNTALK UNTALK is similar to TALK but does not work across machines However on a display terminal UNTALK splits the screen horizontally arid allows the two people to type at the same time on their part of the screen 6 10 4 Mail ITS has several programs for sending and receiving mail These programs d riot actually perform the sending of mail this is handled by a deamon called COMSAT The easiest way to send mail is to run the MAIL program Example 7 September 1982 oom Getting Started Using ITS Page 41 If you type an ALTMODE on an ascii terminal an ESC MAIL will prompt you for a command Type at it to begin using the program s self documentation There are several ways to read your mail The simplist is the PRMAIL command Typing the PRMAIL command at DDT will print your mail and offer to delete it after you have seen it For more flexability you should use a mail reading program such as BABYL The MSGS program will exa
65. rectories recognize an additional category of users those connected to the superior directory A group of users on Tops 20 is a collection of users who will all access a file or directory under the same restrictions A directory can be placed in multiple groups but there is no way to set up different restrictions for different groups Sadly group ids are numbers not symbolic names As such the information about groups given in your directory information will look pretty cryptic A member of user group N has the number N in the User Groups field of his or her directory s information If a directory is accessible to users in group N it will have have the number N in its Directory Groups field of its directory information To see a user group correspondance table look under at the USER GROUPS topic in HELP Here is a sample listing of the table Number Group 10 System source directories 100 Music Hackers 120 Programmer s Apprentice 210 Analogy System Development 300 MUMBLE system 401 Brady shape description 503 LISP sources and libraries 504 EMACS distribution sources 507 LSB sources and libraries 1730 SPICE Circuit Simulator 2000 ACTOR system Figure 7 1 Sample User Groups Table File protection is very useful for safeguarding against accidentally destroying files For example you can set up your directory so that you cannot delete your files without changing the mode of access you are using More information about fil
66. rectory A logical name can provide a generic reference to some direiory whose actual name might change from time to time the logical name is a pointer to the directory even though the directory 8 name might change Logical names may be system wide ordjeb wide Job wide logical names apply only to one user and system wide logical names are defined for all users To define a jab wide logical name usehe define command 7 September 1982 Getting Started Using TOPS 20 Page49 define logical name _ actual pathname 7 6 4 Wildcards You can refer to more than one file at a time This is done by using an asterisk as a pattern matching component of the name The asterisk is a wildcard character it matches any name Here is an example of a filename which specifies all the files in the lt KMP gt directory on the PS structure which have the Name Hu PS lt KMP gt Foo The above file name refers to all these files if they exist PS lt KMP gt FOO LISP 4 PS lt KMP gt FOO LISP 2 PS lt KMP gt FOO QFASL 2 Referring to sets of files using wildcards is especially useful when you are performing a listing renaming or deleting operation 7 6 5 Useful File Manipulation Commands There are many commands which are useful for manipulating files and directories The TYPE command will print out the contents of a file on your terminal The CONNECT command is used to connect to a directory as though you were its owner
67. ripherals usually controlled by a Lisp Machine Briefly Some of these devices are The PUMA robot arm manufactured by Unimation This device is mounted in a special work table whose configuration can be easily rearranged The Frame Grabber which can capture video images from a camera or videotape The Photoscanner which can do high resolution say 20 microns digitization of photographic images 1 Tops 20 and VMS are registered trademarks of Digital Equipment Corporation Unix is a registered trademark of Bell Labs thou shalt not take Ma s name in vain 7 September 1982 Getting Started Introduction Page 4 The Convolution machine a special purpose processor for rapidly computing zero crossings in a digitized image The Linear Array Camera which can take 1000x1000 pixel digital pictures This is connected to the Convolution box 1 3 3 Music Marvin Minsky s Al Music group studies such areas as intelligent music composition tools automatic transcription of music and programs which understand improvisational techniques The group has several Chroma synthesizers which are interfaced to the Lisp Machine 1 3 4 Altos The Al lab has a Xerox Alto minicomputer The Alto is an early 32 bit workstation made by Xerox The Altos was never made commercially available but were used at Xerox s Palo Alto Research Center for a series of interesting experiments involving workstations on Xerox s Ethernet Xer
68. s chapter describes some useful programs and languages which are available on various machines at the lab 3 1 Lisp Lisp is the language most widely used in the Al lab There are several dialects available including MACLISP This dialect of Lisp was developed at MIT under Project MAC A descendant of Lisp 1 5 Maclisp is available on the PDP 10 computers including Al10 and OZ LispM Lisp This is the dialect of Lisp used by the Lisp Machines Among its many features is support for an object oriented programming technique called flavors Lisp Machine Lisp is descended from MacLisp SCHEME Scheme is a dialect of Lisp with lexical scoping Originally created by Gerry Sussman and Guy Steele SCHEME is the Lisp which is currently taught in the undergraduate programming course As part of their research into Al techniques for VLSI design Sussman s group has created a single chip SCHEME interpreter NIL NIL isa new lexically scoped Lisp for the VAX computer It currently runs under VMS i There are several other Lisp dialects such as Franz Lisp Rutgers UCI Lisp and Yale s T language floating around on various machines 3 2 Emacs Emacs is an extensible customizable self documenting display editor Emacs is very powerful and easy to learn and use and is the most freqently used editor on all our machines Once you have used Emacs you will probably not wish to use another editor There are assorted documents conc
69. s the same program as ar existing fork type the name of thie program and use the ALTMODE key to complete it The EXEC will name the new fork FOOn where n indicates how many other forks there are with the same basic name Example emacS EXE 62203 EMACSO Keeping A quick status report showing the current fork s status can be usuudlly be obtained with T at any time in most cases controkc tc will suspend the current process arid giv control to th superior EXEC After suspending a process with the continue command wilt resume the process froin where it 7 September 1982 Getting Started Using TOPS 20 f Page 47 left off continue CONTINUE can be abbreviated to just G You can also tell CONTINUE which fork to resume Thus Gcontinue cftp would continue your CFTP fork Certain programs notably EMACS sometimes work better if they are continued with the command START instead of CONTINUE START restarts the program at a special entry point 7 6 Files On Tops 20 users store data in files To access a file you must know its name File names consist of several component fields the syntax of a file name usually looks like Device XDirectory Namo Extension Generation All the fields in the file name are optional only enough need exist to uniquely identify the file Example PS lt CSTACY gt FOO BAR 3 The Device component tells on what peripheral device on the machine the file resides This is usua
70. seful thing not shown here to do in ari init file is to define some handy logical names for accessing your files 7 10 1 PCL Some users like using an alternate EXEC called the PCL EXEC This EXEC has several features its main virtue being the ability to define new commands and command abbreviations For more information read the HELP information fof PCL 7 11 Using Network protein The FTP program for transferring files from the ARPAnet Internet to OZ is called FTP For transferring files to OZ from the Chaosnet use the CFTP program The TELNET program is called TELNET and the SUPDUP program is called VCHTN These programs are more or less self documenting 7 September 1982 Getting Started References A Page 55 8 References Christman 80 Christman amp Sjobrg The Last Whole XGP Font Catalog Al Memo 197 Artificial Intelligence Laboratory Massachusettes Institute of Technology March 1980 Ciccarelli 78 Ciccarelli An Introduction to the EMACS Editor Al Memo 447 Artificial Intelligence Laboratory Massachusettes Institute of Technology January 1978 Crispin 77 Crispin M SUPDUP Display Protocol RFC 734 Network Information Center SRI International October 1977 NIC 41953 Knuth 80 Knuth Tau Epsilon Chi a system for lechnical text American Mathematical Society 1980 Mathlab 77 Mathlab Macsyma Reference Manual Technical Report Laboratory for Computer Science Massachusettes In
71. site of someone to send the message to The Qsend program prompts you for the message text and then transmits it to the foreign user qsend zvona CADR 22 4 6 Additional Documentation Some other useful documents about the Lisp Machine include Lisp Machine Summary Symbolics by Janet Walker May 1982 System Release Notes which are available online on MIT OZ Introduction to Using the Window System Al Lab Working Paper 210 by Daniel Weinreb and David A Moon May 1981 Lisp Machine Choice Facilities Al Lab Working Paper 208A by David A Moon Revised June 1981 Scroll Windows Symbolics by Bernie Greenberg August 1981 Chaosnet FILE Protocol Symbolics by Eliot Moss and Daniel Weinreb September 1981 7 September 1982 Getting Started The Knight TV System Page 22 5 The Knight TV System For many years the primary way to access Al was from the Knight TV terminal system which was designed by Tom Knight TK MIT Al The Knight TVs are bit mapped frame buffer displays controlled by a small PDP 11 The TV 11 is connected to the PDP 10 via a special PDP10 to PDP 11 interface which allows the PDP 11 s memory to be mapped into the PDP 10 A Knight TV console consists of a CRT display and a keyboard similar to those on the SAIL TV system used at Stanford The TV 11 is connected to a Tektronix electrostatic copier in the eight floor playroom It is possible to copy your screen image to this printer Th
72. stitute of Technology December 1977 Moon 81a Moon Chaosnet Al Memo 628 Artificial Intelligence Laboratory Massachusettes Institute of Technology June 1981 Moon 81b Moon amp Wechsler Operating the Lisp Machine Al Working Paper Artificial Intelligence Laboratory Massachusettes Institute of Technology April 1981 NIC 82a NIC ARPANET DIRECTORY Defense Communications Agency 1982 7 September 1982 Getting Started References Page 56 NIC 82b Internet Protocol Transition WorkBook Defense Communications Agency 1982 Reid 79 Reid B K amp Walker JH SCRIBE Introductory User s Manual Technical Report Carnegie Mellon University July 1979 Shapiro 81 Shapiro R Dover Font Sampler Technical Report Laboratory for Computer Science Massachusettes Institute of Technology September 1981 Snyder 77 Snyder A and Moss Eliot R Reference Manual Stallman 78 Stallman Richard M The SUPDUP Graphics Extension RFC 746 Network Information Center SRI iriechaliondl March 1978 NIC 43796 Stallman 81a Stallman Emacs Manual for ITS Users Al Memo 554 Artificial intelligence Laboratory Massachusettes Institute of Technology April 1981 Stallman 81b Stallman Emacs Manual for TWENEX Users l Al Memo 555 Artificial Intelligence Laboratory Massachusettes Institute of Technology April 1981 Stallman 81c Stallman EMACS The Extensible Customizable Sell Docum
73. the system tries to make users responsible for their actions This is done by requiring certain functions to be done via a special mechanism which keeps audit trails A privileged system deamon called the Protector is always running on MIT OZ Unprivileged programs available to all users contact the Protector and request some special function which the user could otherwise not do The Protector performs the requested function and leaves an appropriate audit trail The most common uses of the Protector mechanism are changing the protection on a file which you need to access creating new accounts managing user directory groups and performing such operations tasks as shutting down the timesharing Under Tops 20 each user s account on Tops 20 has a set of capabilities associated with his account These capabilities determine which privileged operations the user is allowed to perform Before using special capabilities a user must enable then with the ENABLE command When done doing whatever it was that required the capability to be enabled it is usually a good idea to disable the capabilities again When enabled your prompt changes to remind you that you are enabled When you are done using your enabled capabilites you should use the Disable command to revert to your normal capabilities Currently the Protector is not fully implemented To ensure that system security does not get in the way of users all lab members have accounts with capabi
74. tifiers 3 6 SPELL 3 7 Macsyma 3 8 Electronics Design Tools 3 9 FED 4 Using Lisp Machines 4 1 Window System 4 2 booting Pagei X Qoo G N N OO b RWBWAWND 7 September 1982 Getting Starled Table of Contents Page ii 4 3 Logging in 20 4 4 Editing and Compiling 20 4 5 Communication 21 4 6 Additional Documentation 21 5 The Knight TV System 22 6 Using ITS 25 6 1 Logging in l 25 6 1 1 Logging Out 26 6 2 Commands 26 6 2 1 Control Characters 27 6 2 2 More 27 6 3 INFO I 27 6 3 1 System Load 28 6 4 System Security 28 6 5 Jobs 28 6 6 Files 31 6 6 1 Useful File Manipulation Commands 32 6 6 2 Hardcopying files 32 6 6 3 FIND 33 6 7 Terminal Support 33 6 7 1 Wholines 34 6 8 Customization 34 6 8 1 Login inits 35 6 9 Inquire 37 6 10 Communication 37 6 10 1 SENDs 38 6 10 2 Comlinks 38 6 10 3 TALK 40 6 10 4 Mail 40 6 11 Using Network Programs 41 7 Using TOPS 20 42 7 1 Logging in 42 7 2 Commands 42 7 2 1 Control Characters 43 7 2 2 Pausing 43 7 3 Recognition and HELP 43 7 4 System Security 44 7 4 1 File Security 44 7 5 Manipulating Forks 46 7 6 Files 47 7 6 1 Directories 48 7 6 2 Subdirectories 48 7 6 3 Log cal Names 48 7 6 4 Wildcards 49 7 6 5 Useful File Manipulation Commands 49 7 September 1982 Getting Started Table of Contents Page iii 7 6 6 Hardcopying files 49 7 6 7 Creating Directories l 49 7 6 8 Changing Passw
75. u can later get your detached job back by typing the s roman reattach uname K It is important to not leave extraneous job sessions lying around on the system since they consume job slots which could be used by other people 6 2 Commands The usual top level user interface on ITS is DDT the Dynamic Debugging Tool Originally designed for debugging assmebly tangauge programs DDT has a pretty obscure command language There are two sorts of DDT commands short form and long form Most beginners use the long form of commands because they are easier to remember All long form commands are begun with a colon and end with a RETURN Long form commands are single words such as LOGIN COPY and KILL The way to run programs is similar to the way to run commands To run a program type a colon the program s name and press RETURN Example running the WHAT program iwhat You teli me KILL When commands and most programs run to completion they indicate their termination by typing ut KILL A short form exists for many commands This is usually a short obscure sequence of control characters and the ALTMODE character An example of a short form command is x AL TMODE ALTMODE control X period and R control R While these are pretty cryptic many users find that the Twe use the dollar sign to represent the AL TMODE character September 1982 ems Getting Started Using ITS Page 27 short f
76. ul single user computers which are well suited for use in Al research Lisp Machines called LispMs for short are general purpose computers which implement Lisp in microcode Naturally all the system and user software is also written in Lisp Lisp Machines feature dynamic paging over a large address space and a very sophistiated programming environment Each Lisp Machine is connected to the Chaosnet which was mene design d to allow them to communicate The idea behind the Lisp Machine is that one big Lisp environment is made available to the user Inside this environment are various system programs such as the compiler and editor which are useful for writing Lisp programs This environment can as the same unlimited flexability as the Lisp language itself Although most LispMs have a 300 megabyte disk attached to them users do not generally store their files there The disk is used primarily for storing copies of the of the Lisp Machine system world load and microcode files and for dynamic paging space The Lisp Machine has a pathname system which makes it possible to reference file systems on many other computers Most users store their files on a timesharing machine such as OZ or on the Lisp Machine Filecomputer Each Lisp Machine is said to be associated with a particular timesharing machine This association determines such things as where the machine will defaultly assume that the user s files are 4 1 Window System The Lisp M
77. veral thousand recipients on them Mailing lists for sending announcements are usually named INFO something These are intended as receive only lists and you should not send anything but official announcements to them Some examples of this are INFO EMACS and INFO LISPM However note that this riaming convention is not really always adhered to For example INFO MICRO is a general discussion group for microcomputer enthusiasts Frequently the users of a piece of software or hardware will create a mailing list for discussing how the program should evolve announcing new features to users and so forth Bug reports about system programs can be conveniently sent to the maintaner s of program if a mailing list is defined for that purpose This alleviates the problem of knowing who is current ly responsible for each program By convention these mailing lists are name BUG fo6 for example BUG EMACS A related feature for bug reporting via the mail system is that if you se d a message to a non existant BUG mailing list the message will be delivered to a group of general maintainers These people will forward the message to the correct maintaner or perhaps fix the bug themselves Mailing lists are defined in files which are part of the mail syStem for each host The d tails of adding an entry to a mailing list are different for each host and are sometimes a little tricky However you do not need to deal with this problem yourself you

Getting Started Computing at the Al Lab by Christopher C

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