Unix Commands Unix January 2003 This quick reference lists commands, including a syntax diagram 2. Commands and brief description. […] indicates an optional part of the 2.1. Command-line Special Characters command. For more detail, use: Quotes and Escape man command Join Words "…" Use man tcsh for the command language. Suppress Filename, Variable Substitution '…' Escape Character \ 1. Files Separation, Continuation 1.1. Filename Substitution Command Separation ; Wild Cards ? * Command-Line Continuation (at end of line) \ Character Class (c is any single character) [c…] 2.2. I/O Redirection and Pipes Range [c-c] Home Directory ~ Standard Output > Home Directory of Another User ~user (overwrite if exists) >! List Files in Current Directory ls [-l] Appending to Standard Output >> List Hidden Files ls -[l]a Standard Input < Standard Error and Output >& 1.2. File Manipulation Standard Error Separately Display File Contents cat filename ( command > output ) >& errorfile Copy cp source destination Pipes/ Pipelines command | filter [ | filter] Move (Rename) mv oldname newname Filters Remove (Delete) rm filename Word/Line Count wc [-l] Create or Modify file pico filename Last n Lines tail [-n] Sort lines sort [-n] 1.3. File Properties Multicolumn Output pr -t Seeing Permissions filename ls -l List Spelling Errors ispell Changing Permissions chmod nnn filename chmod c=p…[,c=p…] filename 2.3. Searching with grep n, a digit from 0 to 7, sets the access level for the user grep Command grep "pattern" filename (owner), group, and others (public), respectively. c is one of: command | grep "pattern" u–user; g–group, o–others, or a–all. p is one of: r–read Search Patterns access, w–write access, or x–execute access. beginning of line ^ Setting Default Permissions umask ugo end of line $ ugo is a (3-digit) number. Each digit restricts the default any single character . permissions for the user, group, and others, respectively. single character in list or range […] Changing Modification Time touch filename character not in list or range [^…] Making Links ln [-s] oldname newname zero or more of preceding char. or pattern * Seeing File Types ls -F zero or more of any character .* 1.4. Displaying a File with less escapes special meaning \ Run ilename less less f 3. C-Shell Features. Next line RETURN 3.1 History Substitution Next Page SPACE Previous line k Repeat Previous Command !! Previous Page b Commands Beginning with str !str Commands Containing str !?str[?] 1.5. Directories All Arguments to Prev. Command !* Change Directory directory cd Word Designators Make New Directory directory mkdir All Arguments :* Remove Directory directory rmdir Last Argument :$ Print Working (Show Current) Directory pwd First Argument :^ n'th Argument :n Arguments x Through y :x-y Standard Commands whereis file Modifiers Aliases and Commands which command Print Command Line :p Describe Command whatis command Substitute Command Line :[g]s/l/r/ Searching Out Files find dir -name name -print dir is a directory name within which to search. 3.2 Aliases name is a filename to search for. alias Command alias name 'definition' 6.2. Finding Changes definition can contain escaped history substitution event and Comparing Files diff leftfile rightfile word designators as placeholders for command-line arguments. diff prefixes a less-than (<) to selected lines from leftfile and a greater-than (>) to lines from rightfile. 3.3. Variable Substitution 6.3. Automating Tasks Creating a Variable set var Assigning a Value set var = value Create a Makefile pico Makefile Expressing a Value $var A makefile consists of macro definitions and targets. Displaying a Value echo $var Test Makefile make -n [target] value is a single word, an expression in quotes, or an Run make make [target] expression that results in a single word after variable, 6.4. Managing Disk Usage filename and command substitution takes place. Assigning a List set var = (list) Check Quota quota -v list is a space-separated list of words, or an expression that Seeing Disk Usage df results in a space-separated list. du -s Selecting the n'th Item $var[n] 6.5. Combining and Compressing Files Selecting all Items $var Create a tarfile file file1 file2 … fileN Selecting a Range $var[x-y] tar cf .tar tar combines files but does not compress Item Count $#var Create a zipfile zip filename 3.4 foreach Lists Unzip a file unzip filename Start foreach Loop foreach var (list) 7. Printing foreach prompts for commands to repeat for each item in list (with >), until you type end. Within the loop, $var 7.1 Formatting Output for Printing stands for the current item in list. Paginate with Page Headers pr filename in n columns pr -n filename 3.5. Command Substitution Format for Laser Printer tex document Replace Command with its Output on Command Line `…` 7.2 The Printer Queue 3.6 Job Control Print a File lp [-dpr] filename Run Command in the Background & lpcae filename Stop Foreground Job CTRL-Z Check Quota lpquot List of Background Jobs jobs List Queue lpq Bring Job Forward %[n] Stop Job lprm Resume Job in Background %[n] & 8. Miscellaneous 4. Processes 8.1 Miscellaneous Commands Listing ps [-[ef]] List Commands for Subject subject Terminating kill [-9] PID man -k Display Current Date and Time Timing time command date time is a number up to 4 digits. script is the name of a file Log off exit containing the command line(s) to perform. Electronic Mail pine Display Documentation man command 5. Users 8.2 Control Keys Seeing Who is Logged In who Abort Program CTRL-C w Backspace (Delete Last Character) CTRL-H Seeing Your User Name whoami Pause Display on Screen CTRL-S Resume Display after CTRL-S CTRL-Q 6. Managing Files Send Job to Background CTRL-Z followed by bg 6.1. Looking Up Files Is this document clear? Is it missing crucial information? Please mail comments to the handout editor, CAE, 1410 Engineering Drive, or to: [email protected] .