UNIX-Linux Shell Cheat Sheet.pdf

http%MMsteve5par/er.orgMshMsh.shtml

v1.1 – 7 Aug 2007

UNI / !inu" #hell $heat #heet

File %anipulation

&est 'perators

(ariable #ubstitution

> file >> file >file 2>1 + file a,!

if N "* 5lt "3* O then # do something fi

"$%5def' "$% "$%8d 8def ef' ' "$%&err'

Numeri) &ests

$onditional *"e)ution

lt gt e ne ge le

c1 ,, c2 c1  c2

create (overwrite) file append to file !oth output and errors to file read from file pipe output from -a- as input to -!-

$ommon $onstru)ts while read f do echo ine is "f* done + file

read tet file line !3 line

" grep foo m3file afoo foo foo!ar

find matching lines

less than greater than eual to not eual greater or eual less or eual

File &ests

" cut 5d% 5fQ MetcMpasswd :il!ert

get field with delimiter

foo8PlsP

get output of command

case "foo in a) echo foo is A*  !) echo foo is T*     ) echo foo is not A or T*   es  esac dou!leit()  epr "1 R 2 ' dou!leit B # returns U

case is a good wa3 to avoid iterating through man3 ifMelifMelifMelif constructs.

function declaration and calling s3nta

nt d f r w 

newer than is a director3 is a file reada!le writea!le eecuta!le

#tring &ests

8 4 n

eual to 4ero length not 4ero length

!ogi)al &ests

 ,, <

logical A9: logical ; logical 9;=

"$ or def* if unset "$ (set (set to def def* * if unse unset) t) "$ or err* if unset

run c1 if it fails run c2 run c1 if it wor/s run c2

$ommon utilities and s+it)hes ls 5lHr ls 5ltr ls 5lh du 5s/  sort 5n ps 5ef wget 6 time cm cmd touch file read  cmd , R tee file.tt nice ice cmd cmd

list files !iggest last list files newest last human5reada!le filesi4es director3 si4es (slow) sort numericall3 (not alpha) list  m3 commands download 6 stopwatch on on Pc PcmdP create file read * from /e3!oard cmd output to stdout and also to file.tt run cmd cmd with low priorit3

Net+orking ifconfig 5a netstat 5r ssh uShost scp scp file file.t .tt t R uShost%% uShost

list all networ/ interfaces show routers log in to host as user u* cop3 cop3 file file.t .tt t to host host as user u*

Argument (ariables

,eneral Admin

"0 "1 "2 ... "@ " "#

less file alias l8-ls 5ltar cf t.tar R list?of?files cal B 1@7B df 5h truss 5p CD:

program name 1st argument 2nd ar  a rgument ... @th ar  a rgument all arguments 9o. of arguments

displa3 file page !3 page create l* as alias for ls 5l* create a tar archive t.tar from the listed dirsMfiles displa3 a calendar (ar 7B) show dis/ mounts show s3scalls of CD:

Files: $ontents / Attributes for i in  do echo File is "i* done

A for loop iterates through its input (which is su!Gect to glo!!ing)

find . 5si4e 10/ 5print find . 5name .tt* 5print find Mfoo 5t3pe d 5ls three8Pepr 1 V 2P echo Wscale 8 Q  Q121 M 102X* , !c egrep (foo,!ar)* file

Useful (ariables "DFH "& "HIJ A9K

Dnternal File Heparator return code from last program what shell ell is running this script& anguage L is 6H Jnglish

aw/ - print "Q '- file sed sMfooM!arMg file

files over 10E! find tet files ls all directories under Mfoo simple maths !etter maths find foo* or !ar* in file print the Qth word of each line replace foo* in file with !ar*

A full PDF and online tutorial is available at http://steve-parker.org/sh/sh.shtm http://steve-parker.org/sh/sh.shtmll