.ps +2 .vs +2 slide0 Course: Introduction to Unix, a hands-on seminar. Sponsor: St. John Fisher College Office of Professional Development Course Leaders: Gerry Wildenberg (wizard) St John Fisher College Carol Freeman (apprentice) Finger Lakes Community College .bp What is UNIX? slide1 + Ken Thompson and Dennis Ritchie + What is an operating system? + What is a shell? + The C language + Unix and you + Electronic mail + File handling tools + Data base tools + Documentation facilities .bp Getting started slide2 + Logging in login: guest1 password:VAXsys (but you won't see it when you type it.) + Prompts Vary from system to system. Many books use %. I'll use % or [] . + Passwords + passwd [1] + various rules about length and variety of characters. Try some. + Logging out + logout (or exit or ... ) + Delete or backspace? + User can set + Some simple commands + date [3] + echo [5] + cal [6] + Correcting errors in the csh [2] + Reading files with cat [16] + more or less [11] more is a "pager". It lets you page through a file. At the more prompt, h, b, q, , and are the most useful keys. /pattern will do a search. .bp Which shell? slide2.1 + Changing shells -- csh, sh, or tcsh + chsh .bp Elementary redirection slide3 echo % echo This is sentence 1 This is sentence 1 % echo This is sentence 1 > sfile % echo This is sentence 2 > sfile % cat sfile This is sentence 2 % echo This is sentence 1 > sfile % echo This is sentence 2 >> sfile % cat sfile This is sentence 1 This is sentence 2 % echo > sfile % cat sfile % .bp cal slide4 %cal 3 1987 March 1987 S M Tu W Th F S 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 %cal 3 1987 > cfile .bp slide4.1 Excercises (1) Login (2) Give yourself a password (3) Logout and login again (4) Print a calendar for your birth-year (5) Print a calendar for December 1995 (6) What day of the week were you born? (7) How many days were in the month September 1752? Be sure to do this one, it's fun. (8) Try echoing some messages. (9) Find out the time and date. (10) Change the erase key to '='. Try hitting . Change erase back to .bp Communications slide5 + mail [7] mail mail name mail namealias + talk [8] + /etc/passwd [9] + grep [10] + who [4] .bp mail and grep slide6 % mail ggww Dear Gerry: I'm finally on the system!!!!!!!! David . % %grep Rako /etc/passwd bdr:v0rdA2Pe82jQE:22:700:RakoverBoris :/fs3/fac/bdr:/bin/csh .bp mail - some details slide6.1 Some commands to use at the "mail prompt". + t type + n next message + v edit waiting message + d " " delete + s file saves messages in file + u undeletes (only works if you are still in same mail session.) + r reply to everyone who received the letter + R reply to sender only + q quits (read mail is saved) + h print out headers .bp slide6.2 biff -- the dog that barked at the mailman biff n biff y biff talk -- can be annoying, mesg can help talk joe mesg n or mesg y .bp who and finger slide7 %who ep7956 ttyaf Feb 13 21:35 ggww ttyah Feb 13 22:00 uucp ttyat Feb 13 21:33 sl8860 ttybb Feb 13 21:35 %finger Login Name TTY Idle When Office ep7956 Eric Periche af 57 Fri 21:35 ggww Gerry Wildenberg ah Fri 22:00 uucp UNIX-to-UNIX Copy *at Fri 21:33 sl8860 Steven Lape bb Fri 21:35 %finger freeman Login name: clf In real life: Carol Freeman Directory: /faculty/clf Shell: /bin/csh Last login Wed Apr 27 21:13 on ttyp6 from ds703-Modem No Plan. .bp Learning by yourself slide8 + man [12] man cat + apropos [13] (man -k if you don't like spelling apropos.) %apropos pascal pc (1) - Pascal compiler pdx (1) - pascal debugger pi (1) - Pascal interpreter code translator pix (1) - Pascal interpreter and executor pmerge (1) - pascal file merger px (1) - Pascal interpreter pxp (1) - Pascal execution profiler pxref (1) - Pascal cross-reference program Time: 0:20;O:20 to infinity. .bp Filenames in the shell slide9 + Names may use any letters, numbers and special characters. + E.g. legal names: a rumplestiltskin 123 file.out.bak = one big name + The following are metacharacters: * ? [ ] ~ . ' " $ (Usually not a good idea to make them part of a file name.) + / and \ (slash and back-slash) have special meanings + ! and ^ (bang and caret) have a special meaning .bp Metacharacters slide9.1 * matches any string ? matches any character [...] matches any character in the brackets ~ short for: home directory . short for: current directory ' quotes strings containing metachacters " quotes strings containing metachacters $ used to denote shell variable \ "Escapes" or "quotes" the next character / The separator in paths. !^ The history mechanism. .bp Cat and ls slide10 + stdin and stdout + Creating files with cat + Redirection cat > newfile + Combining files with cat + More redirection cat a b > c cat a>c cat b>>c + ls is a simple command to list your files. (See slide 14 for more about ls) .bp SUGGESTED EXERCISES (11) Create a file containing a calendar. (Inspect it, using cat ) Add a line commenting on the calendar. Inspect the file again. (12) Create a file containing the calendar for the years 1985, 1986 and 1987 Inspect this file using 'more'. (13) Use cat to create a file. Use cat to combine two files. (14) Use apropos to see if there is any way to get phone information. Try it. (15) By now you have a few files. Try different ways of listing them. (ls, ls -a, ls -l,ls [a-z]*, etc. Try listing only some of them. .bp File handling commands slide11 + Moving files with mv [17] mv oldname newname + Copying files with cp [18] cp oldfile newcopy cp file1 file2 file3 somedirectory cp ~ggww/teach-vi . + Removing files rm file1 rm * rm -i .bp Editing with the screen editor slide12 + vi [20] vi filename Exercise A. Copy /usr/local/skel/teach-vi to your directory. (cp /usr/local/skel/teach-vi . ) The '.' IS part of the command. Then use vi to edit teach-vi. (vi teach-vi) Try the stuff in teach-vi. B. This is an alternative to A. (above) Use vi to edit a file you've created. Try the commands on the summary sheet. .bp Editing with the line editor slide13 + ex (ed edit) [19] A few commands: :a append (a line with only a period '.' ends inserting) :s substitute :w write current version of buffer :q! Leaves the editor without saving the changes made since last :w (If no :w this session, then no changes are saved.) :q quit editing :vi Switch to visual editing. .bp Magic characters in the line editor slide13.1 . any character * 0 or more occurrences of a string character. [xyz] Any of x,y or z] [a-z] Any of a through z ^ Beginning of line. $ End of line. [^a-zA-Z] Any non-letter. & On right means string from left. \ Turns the magic off. .bp Addressing instructions slide13.2 :se nu Line numbers are seen. :se nonu No line numbers shown, but they still work :n1,n2 Print lines n1 to n2 :. Print this line :.,+10 Print this line and 10 more. :.,-10 Print this line and 10 preceding. :/str/ Find next occurrence of str. :?str? Find previous occurrence of str. :/ Repeat the last search. :$ The last line in the buffer. :1,$ Print whole file. :% Shorthand for 1,$ :-10 Go back 10 lines. :.,.+10w! temp Write this line and next 10 into a file called temp, overwriting "temp" if it previously existed. .bp Some examples slide13.3 :s/str1/str2/ The first occurrence of str1 on this line is changed to str2. :1,10s/str1/str2/ On lines 1 to 10, changes the first occurrence of str1 to str2. :%s/str1/str2/g Change all occurences of str1 to str2. :g/^$/d Removes all blank lines. :/^[^a-zA-Z]/ Go to next line with a non-letter as first character. (Note two uses of ^) :%s/[^:]*:// On every line remove everything up to and including the first colon. :%s/:.*// Removes the ':' and everything which follows on the current line. .bp Files and directories slide14 + Your home directory's path name pwd + The file system + ls [15] + ls + ls -l + ls -a + ls -l a* .bp Directories and abbreviations slide15 + Directories and files are a tree structure + Creating directories with mkdir [21] + Removing directories with rmdir [22] + Where am I? pwd [23] + Removing a non-empty directory with rm -r + Wild card abbreviations + Special abbreviations ( . .. ~ ) .bp Protection Codes slide15.1 + Protection codes + chmod [24] + Protection codes for directories + ls with special treatment of directories. + ls -d + ls -d * + ls -ld slide15.2 SUGGESTED EXERCISES (16) Rename some of your files. (17) Copy a file. Remove the old one. (Use ls to verify the copying and the removal.) (18) Use ex on any file. Try some of the powerful commands. (E.g. Try inserting a space before any character which is not a space.) (19) Change into the parent directory of your "home". Look around. Do the same for /usr/bin. (20) Create a directory. Copy some files into the new direc- tory. Change to the new directory. Create some files in there. Change back to your home directory and try some different 'ls' commands. (21) Try pwd in different directories. Try cd and cd .. . Create and remove a directory. Try putting a file into the directory first. (22) Change the protection code so that your neighbor can read one of your files. Do this inside a newly made directory. .bp Pipes and Filters slide16 + What is a filter? + fmt [26] .nf %cat sloppy This is a sloppily written letter. It has short lines like the one above and lines that are really much too long as is this one. %fmt sloppy This is a sloppily written letter. It has short lines like the one above and lines that are really much too long as is this one. + wc [28] %wc sloppy 2 26 135 sloppy + head (tail) [29] .bp Sort [25] slide16.1 % cat inventory McCall,Joan :ATH : :MIC :Seequa Chameleon Plus :10753 Continuing Ed :CED : :PRT :Daisy Writer Printer :41039078 Biology Lab :BIO :S-206 :MIC :Apple II Plus :A252-359-792 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10387 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10664 McCall,Joan :ATH : :PRT :Televideo Letter Quality :613-08679 Continuing Ed :CED :K-202 :MIC :Seequa Chameleon Plus :50505 Continuing Ed :CED : :PRT :Mannesmann Tally Spirit 80 :1020450 %sort inventory Biology Lab :BIO :S-206 :MIC :Apple II Plus :A252-359-792 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10387 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10664 Continuing Ed :CED : :PRT :Daisy Writer Printer :41039078 Continuing Ed :CED : :PRT :Mannesmann Tally Spirit 80 :1020450 Continuing Ed :CED :K-202 :MIC :Seequa Chameleon Plus :50505 McCall,Joan :ATH : :MIC :Seequa Chameleon Plus :10753 McCall,Joan :ATH : :PRT :Televideo Letter Quality :613-08679 .bp Sort [25] slide16.2 %sort -t: +1 inventory McCall,Joan :ATH : :MIC :Seequa Chameleon Plus :10753 McCall,Joan :ATH : :PRT :Televideo Letter Quality :613-08679 Biology Lab :BIO :S-206 :MIC :Apple II Plus :A252-359-792 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10387 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10664 Continuing Ed :CED : :PRT :Daisy Writer Printer :41039078 Continuing Ed :CED : :PRT :Mannesmann Tally Spirit 80 :1020450 Continuing Ed :CED :K-202 :MIC :Seequa Chameleon Plus :50505 %sort -t: +4.3 inventory McCall,Joan :ATH : :PRT :Televideo Letter Quality :613-08679 Biology Lab :BIO :S-206 :MIC :Apple II Plus :A252-359-792 Continuing Ed :CED : :PRT :Mannesmann Tally Spirit 80 :1020450 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10387 Continuing Ed :CED :K-202 :MIC :Seequa Chameleon Plus :50505 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10664 McCall,Joan :ATH : :MIC :Seequa Chameleon Plus :10753 Continuing Ed :CED : :PRT :Daisy Writer Printer :41039078 .bp slide16.2.1 % sort -t: +1 -2 +5 inventory McCall,Joan :ATH : :MIC :Seequa Chameleon Plus :10753 McCall,Joan :ATH : :PRT :Televideo Letter Quality :613-08679 Biology Lab :BIO :S-206 :MIC :Apple II Plus :A252-359-792 Continuing Ed :CED : :PRT :Mannesmann Tally Spirit 80 :1020450 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10387 Continuing Ed :CED : :MIC :Seequa Chameleon Plus :10664 Continuing Ed :CED : :PRT :Daisy Writer Printer :41039078 Continuing Ed :CED :K-202 :MIC :Seequa Chameleon Plus :50505 .bp Pipes slide16.3 + What is a pipe? + Some examples of pipes How many users are on? %who | wc 8 40 240 Is there an English word that can be made using only the letters a, l, r, t? %cat /usr/dict/words | grep l | grep a | grep t| grep r | grep -v '[b-km-qsu-z]' altar Find the five most frequent words in any file (slides in this example): %cat slides | tr -sc 'A-Za-z' '\012' | sort | uniq -c | sort -n | tail -5 27 A 28 the 29 a 29 and 51 slide A couple of other examples: tail +200 anyfile | head -20 (Prints lines 200-219 of file.) Exercise: Find line 9980 in /usr/dict/words du -a | grep anyfile (Useful for locating a "lost" file.) .bp A few miscellaneous commands slide16.4 + su changing identities + sed a filter to learn someday (Like awk but faster and easier and less powerful) + file when you don't know what you have + od for computer experts only .bp Making UNIX suit you slide17 + .login %cat .login set path=(. /usr/local/bin /usr/ucb /bin /usr/bin /usr/new /usr/rt11) echo '' stty crt + .cshrc set prompt='[\!]: ' set history=10 set mail=/usr/spool/mail/`whoami` alias cd 'cd \!*;dirs' alias h history -r alias l ls -la + .profile .bp Your Own Commands slide18 + alias (C-shell only) alias back 'set back=$old; set old=$cwd; cd $back; unset back' alias ampex 'setenv TERM ampex;set term=ampex; stty erase ' alias h history -r + Shell scripts + shells - write new commands into a file, then they can be tested and modified without retyping each time. But remember to make the file executable. + source + csh Exercises (23) Use a pipe to write a one line command to find out if your neighbor is logged on. This command shouild have only one line of output (24) Use fmt from inside of vi. (25) Use "head /etc/passwd > shortpw" to get part of the passwd file into your own account. Use sort to sort shortpw in various ways. (Note that the field separa- tor is ":". (26) Add a command or two to your .login file. Add an alias to your .cshrc file. Login again and try them. .bp Documentation aids slide19 + nroff -me [30] + spell [31] + diction [32] (Often available, but not on this system.) .bp C-shell features slide20 + history [33] !! ls !$ !12 !ls !ls:p !ls:1-3 !ls:^ !ls:$ + Stopping and restarting jobs fg bg Suggested Exercises (27) Start editing a file. Use to stop it. Try some other commands. Restart the editing job. (28) Use some features of the history mechanism to repeat commands. (30) Combine head and tail using pipes to see the 10th 11th and 12th lines of a file. (31) Try the file command on various groups of files. (32) How many files are in /usr/bin ? (33) Print out the names of the five largest files in /etc .bp Footnotes --------- [1] passwd-A program to change passwords. [2] csh-A popular "shell". [3] date-A program that prints the time and date. [4] who-A program that shows who else is working. [5] echo-A program that repeats it's input. [6] cal-A program that prints a calendar of any year or month. [7] mail-A program to send or read electronic mail. [8] talk-A program that allows you to type messages back and forth between terminals. [9] /etc/passwd-The password file. [10] grep-A string searching program. [11] more,less-Programs to examine large files at a relaxed pace. (Less is seen less often these days.) [12] man-A program that prints out a section of the manual. [13] apropos-A program that examines the manual's index and finds anything appropriate. [14] learn-A computer teaching program (now unavailable) [15] ls-A program that lists your files and direc- tories. [16] cat-A program that outputs files. [17] mv-A program to rename files and move files into directories. [18] cp-A program to copy files. .bp Glossary [19] ed,edit,ex-Different versions of the most popular UNIX text editor. [20] vi-A visual (screen) editor. [21] mkdir-A program to create sub-directories. [22] rmdir-A program that removes (empty) directories. [23] pwd-Print Working Directory - reminds you where you are. [24] chmod-CHange MODe, lets you make files and direc- tories more or less available to others. [25] sort-Sorts files,by lines, almost any way you can imagine. [26] fmt-The simplest formatting program in UNIX. [27] pr-A program that prepares files for printing. [28] wc-Word Count--Counts the lines words and charac- ters in a file. [29] head (tail)-Lets you see just the first (last) lines of a file. [30] nroff-A word processing program. [31] spell-Checks your spelling. [32] diction-Checks for awkward or incorrect phrases. [33] history-Lists your recent commands. slide0 What is UNIX? slide1 Getting started slide2 Which shell? slide2.1 Elementary redirection slide3 cal slide4 Communications slide5 mail and grep slide6 mail - some details slide6.1 who and finger slide7 Learning by yourself slide8 Filenames in the shell slide9 Metacharacters slide9.1 Cat and ls slide10 (See slide 14 for more about ls) File handling commands slide11 Editing with the screen editor slide12 Editing with the line editor slide13 Magic characters in the line editor slide13.1 Addressing instructions slide13.2 Some examples slide13.3 Files and directories slide14 Directories and abbreviations slide15 Protection Codes slide15.1 Pipes and Filters slide16 Sort [25] slide16.1 Sort [25] slide16.2 slide16.2.1 Pipes slide16.3 Making UNIX suit you slide17 Your Own Commands slide18 Documentation aids slide19 C-shell features slide20