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Commands tagged awk from sorted by
Terminal - Commands tagged awk - 280 results
cat /dev/urandom|awk 'BEGIN{"tput cuu1" | getline CursorUp; "tput clear" | getline Clear; printf Clear}{num+=1;printf CursorUp; print num}'
2009-07-13 07:30:51
User: axelabs
Functions: awk cat printf
Tags: nawk awk clear tput
0

awk can clear the screen while displaying output. This is a handy way of seeing how many lines a tail -f has hit or see how many files find has found. On solaris, you may have to use 'nawk' and your machine needs 'tput'

awk '{c=split($0, s); for(n=1; n<=c; ++n) print s[n] }' INPUT_FILE > OUTPUT_FILE
2009-07-06 06:10:21
User: agony
Functions: awk
Tags: awk
0

Basically it creates a typical word list file from any normal text.

echo "${STRING}" | tr '[A-Z]' '[a-z]' | awk '{print toupper(substr($0,1,1))substr($0,2);}'
2009-06-23 21:11:34
User: mohan43u
Functions: awk echo tr
Tags: awk tr
0

Helpful when we want to do mass file renaming(especially mp3s).

for x in `seq -w 1 30`; do sar -b -f /var/log/sa/sa$x | gawk '/Average/ {print $2}'; done
svn log -v -r{2009-05-21}:HEAD | awk '/^r[0-9]+ / {user=$3} /yms_web/ {if (user=="george") {print $2}}' | sort | uniq
2009-06-05 14:07:28
User: jemptymethod
Functions: awk sort
Tags: svn awk log
4

just change the date following the -r flag, and/or the user name in the user== conditional statement, and substitute yms_web with the name of your module

awk '/match/{print NR}' file
cat somefile.css | awk '{gsub(/{|}|;/,"&\n"); print}' >> uncompressed.css
2009-06-02 15:51:51
User: lrvick
Functions: awk cat
0

Ever compress a file for the web by replacing all newline characters with nothing so it makes one nice big blob?

It is a great idea, however what about when you want to edit that file? ...Serious pain in the butt.

I ran into this today in that my only copy of a CSS file was "compressed" with no newlines.

I whipped this up and it converted back into nice human readable CSS :-)

It could be nicer, but it does the job.

awk 'BEGIN{srand()}{print rand(),$0}' SOMEFILE | sort -n | cut -d ' ' -f2-
2009-05-29 01:20:50
User: axelabs
Functions: awk cut sort
Tags: sort awk random
4

This appends a random number as a first filed of all lines in SOMEFILE then sorts by the first column and finally cuts of the random numbers.

awk 'BEGIN{size=5} {mod=NR%size; if(NR<=size){count++}else{sum-=array[mod]};sum+=$1;array[mod]=$1;print sum/count}' file.dat
2009-05-29 00:07:24
User: mungewell
Functions: awk
2

Sometimes jittery data hides trends, performing a rolling average can give a clearer view.

svn log fileName|cut -d" " -f 1|grep -e "^r[0-9]\{1,\}$"|awk {'sub(/^r/,"",$1);print "svn cat fileName@"$1" > /tmp/fileName.r"$1'}|sh
2009-05-27 02:11:58
User: fizz
Functions: awk cut grep
Tags: bash svn awk grep
2

exported files will get a .r23 extension (where 23 is the revision number)

wget -q -O- http://www.gutenberg.org/dirs/etext96/cprfd10.txt | sed '1,419d' | tr "\n" " " | tr " " "\n" | perl -lpe 's/\W//g;$_=lc($_)' | grep "^[a-z]" | awk 'length > 1' | sort | uniq -c | awk '{print $2"\t"$1}'
2009-05-04 16:00:39
User: alperyilmaz
Functions: awk grep perl sed sort tr uniq wget
-4

This command might not be useful for most of us, I just wanted to share it to show power of command line.

Download simple text version of novel David Copperfield from Poject Gutenberg and then generate a single column of words after which occurences of each word is counted by sort | uniq -c combination.

This command removes numbers and single characters from count. I'm sure you can write a shorter version.

vmstat 1 10 | /usr/xpg4/bin/awk -f ph-vmstat.awk
2009-05-04 04:55:00
User: MarcoN
Functions: vmstat
5

% cat ph-vmstat.awk

# Return human readable numbers

function hrnum(a) {

b = a ;

if (a > 1000000) { b = sprintf("%2.2fM", a/1000000) ; }

else if (a > 1000) { b = sprintf("%2.2fK", a/1000) ; }

return(b) ;

}

# Return human readable storage

function hrstorage(a) {

b = a ;

if (a > 1024000) { b = sprintf("%2.2fG", a/1024/1024) ; }

else if (a > 1024) { b = sprintf("%2.2fM", a/1024) ; }

return(b) ;

}

OFS=" " ;

$1 !~ /[0-9].*/ {print}

$1 ~ /[0-9].*/ {

$4 = hrstorage($4) ;

$5 = hrstorage($5) ;

$9 = hrnum($9) ;

$10 = hrnum($10) ;

$17 = hrnum($17) ;

$18 = hrnum($18) ;

$19 = hrnum($19) ;

print ;

}

p=$(netstat -nate 2>/dev/null | awk '/LISTEN/ {gsub (/.*:/, "", $4); if ($4 == "4444") {print $8}}'); for i in $(ls /proc/|grep "^[1-9]"); do [[ $(ls -l /proc/$i/fd/|grep socket|sed -e 's|.*\[\(.*\)\]|\1|'|grep $p) ]] && cat /proc/$i/cmdline && echo; done
2009-04-30 12:39:48
User: j0rn
Functions: awk cat grep ls netstat sed
-5

Ok so it's rellay useless line and I sorry for that, furthermore that's nothing optimized at all...

At the beginning I didn't managed by using netstat -p to print out which process was handling that open port 4444, I realize at the end I was not root and security restrictions applied ;p

It's nevertheless a (good ?) way to see how ps(tree) works, as it acts exactly the same way by reading in /proc

So for a specific port, this line returns the calling command line of every thread that handle the associated socket

dpkg-query -l| grep -v "ii " | grep "rc " | awk '{print $2" "}' | tr -d "\n" | xargs aptitude purge -y
2009-04-28 19:25:53
User: thepicard
Functions: awk grep tr xargs
-3

This will, for an application that has already been removed but had its configuration left behind, purge that configuration from the system. To test it out first, you can remove the last -y, and it will show you what it will purge without actually doing it. I mean it never hurts to check first, "just in case." ;)

sudo apt-get remove --purge `dpkg -l | awk '{print $2}' | grep gnome` && apt-get autoremove
2009-04-28 10:34:42
User: kelevra
Functions: awk grep sudo
Tags: awk apt-get dpkg
-4

Useful for removes a package and its depends, for example to remove the gnome desktop environment, also configuration files will be removed, you should be carefully and sure that you want to do this.

ifconfig en1 | awk '/inet / {print $2}' | mail -s "hello world" email@email.com
2009-04-28 06:01:52
User: rez0r
Functions: awk ifconfig mail
9

This is useful if you have need to do port forwarding and your router doesn't assign static IPs, you can add it to a script in a cron job that checks if you IP as recently changed or with a trigger script.

This was tested on Mac OSX.

svn status | grep '^?' | awk '{ print $2; }' | xargs svn add
2009-04-10 21:55:37
Functions: awk grep xargs
Tags: svn awk xargs
1

Lists the local files that are not present in the remote repository (lines beginning with ?)

and add them.

awk '{print > $3".txt"}' FILENAME
2009-03-31 15:14:13
User: alperyilmaz
Functions: awk
2

This command will sort the contents of FILENAME by redirecting the output to individual .txt files in which 3rd column will be used for sorting. If FILENAME contents are as follows:

foo foo A foo

bar bar B bar

lorem ipsum A lorem

Then two files called A.txt and B.txt will be created and their contents will be:

A.txt

foo foo A foo

lorem ipsum A lorem

and B.txt will be

bar bar B bar

netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
2009-03-28 21:02:26
User: tiagofischer
Functions: awk cut netstat sort uniq
14

Here is a command line to run on your server if you think your server is under attack. It prints our a list of open connections to your server and sorts them by amount.

BSD Version:

netstat -na |awk '{print $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr
awk '{sum+=$1; sumsq+=$1*$1} END {print sqrt(sumsq/NR - (sum/NR)**2)}' file.dat
seq 0 0.1 20 | awk '{print $1, cos(0.5*$1)*sin(5*$1)}' | graph -T X
2009-03-24 21:46:59
User: kaan
Functions: awk seq
2

The arguments of "seq" indicate the starting value, step size, and the end value of the x-range. "awk" outputs (x, f(x)) pairs and pipes them to "graph", which is part of the "plotutils" package.

seq 6 | awk '{for(x=1; x<=5; x++) {printf ("%f ", rand())}; printf ("\n")}'
2009-03-24 21:33:38
User: kaan
Functions: awk printf seq
Tags: awk seq
3

Displays six rows and five columns of random numbers between 0 and 1. If you need only one column, you can dispense with the "for" loop.

awk '{sum1+=$1; sum2+=$2} END {print sum1/NR, sum2/NR}' file.dat
2009-03-24 21:22:14
User: kaan
Functions: awk
Tags: awk
2

This example calculates the averages of column one and column two of "file.dat". It can be easily modified if other columns are to be averaged.

seq 50| awk 'BEGIN {a=1; b=1} {print a; c=a+b; a=b; b=c}'
2009-03-24 20:39:24
User: kaan
Functions: awk seq
Tags: awk seq
13

Another combination of seq and awk. Not very efficient, but sufficiently quick.

seq 100 | awk '{sum+=$1} END {print sum}'
2009-03-24 20:30:40
User: kaan
Functions: awk seq
Tags: awk seq
4

"seq 100" outputs 1,2,..,100, separated by newlines. awk adds them up and displays the sum.

"seq 1 2 11" outputs 1,3,..,11.

Variations:

1+3+...+(2n-1) = n^2

seq 1 2 19 | awk '{sum+=$1} END {print sum}' # displays 100

1/2 + 1/4 + ... = 1

seq 10 | awk '{sum+=1/(2**$1)} END {print sum}' # displays 0.999023