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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
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2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




Commands using awk from sorted by
Terminal - Commands using awk - 1,116 results
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

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.

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

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

w | egrep -v '(load|FROM)' | awk '{print $2}' | sed 's/^/tty/' | awk '{print "echo \"The Matrix has you...\" >> /dev/" $1}' | bash
2009-04-29 22:04:56
User: copremesis
Functions: awk egrep sed

This works just like write or wall ... cept one thing the sender is anonymous ... if you really want to drive everyone insane replace echo \"The Matrix has you...\" with cat /dev/urandom

nice one to do on April fool's day

ps auxf | grep httpd | grep -v grep | grep -v defunct | awk '{sum=sum+$6}; END {print sum/1024}'
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

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 aptitude purge `dpkg --get-selections | grep deinstall | awk '{print $1}'`
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

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

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.

netstat -an | grep ESTABLISHED | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }'
2009-04-27 22:02:19
User: knassery
Functions: awk grep netstat sort uniq

Written for linux, the real example is how to produce ascii text graphs based on a numeric value (anything where uniq -c is useful is a good candidate).

awk 'BEGIN {srand()} {print int(rand()*1000000) "\t" $0}' FILE | sort -n | cut -f 2-
2009-04-19 20:04:58
User: udim
Functions: awk cut sort

Replace FILE with a filename (or - for stdin).

find /path/to/my/files/ -type f -name "*txt*" | xargs du -k | awk 'BEGIN{x=0}{x=x+$1}END{print x}'
2009-04-16 14:17:04
Functions: awk du find xargs

Use the find command to match certain files and summarise their total size in KBytes.

awk '/sshd/ && /Failed/ {gsub(/invalid user/,""); printf "%-12s %-16s %s-%s-%s\n", $9, $11, $1, $2, $3}' /var/log/auth.log
2009-04-16 00:56:23
User: frailotis
Functions: awk printf

A variation of a script I found on this site and then slimmed down to just use awk. It displays all users who have attempted to login to the box and failed using SSH. Pipe it to the sort command to see which usernames have the most failed logins.

/sbin/ifconfig -a | awk '/(cast)/ { print $2 }' | cut -d':' -f2 | head -1
find | sed -e "s/^.*\///" | awk ' BEGIN { FS=""} { print NF " " $0 } ' | sort -nrf | head -10
cd ~/.mozilla/firefox/ && sqlite3 `cat profiles.ini | grep Path | awk -F= '{print $2}'`/formhistory.sqlite "select * from moz_formhistory" && cd - > /dev/null
2009-04-13 20:23:37
User: klipz
Functions: awk cd grep

When you fill a formular with Firefox, you see things you entered in previous formulars with same field names. This command list everything Firefox has registered. Using a "delete from", you can remove anoying Google queries, for example ;-)

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

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

and add them.

grep "install " /var/log/dpkg.log | awk '{print $4}' | xargs apt-get -y remove --purge
history|awk '{print $2}'|awk 'BEGIN {FS="|"} {print $1}'|sort|uniq -c|sort -r
2009-04-05 13:40:56
User: kayowas
Functions: awk sort uniq

It will return a ranked list of your most commonly-entered commands using your command history

find . -type f -size +25000k -exec ls -lh {} \; | awk '{ print $8 ": " $5 }'
nmap -sP your network/submask | awk "/^Host/"'{ print $2 }'
2009-04-02 12:41:54
User: rauhmaru
Functions: awk

This command will display only the hosts that are active in the network.

find ./ -not -type d | xargs wc -l | cut -c 1-8 | awk '{total += $1} END {print total}'
man beep | sed -e '1,/Note/d; /BUGS/,$d' | awk '{print $2}' | xargs -IX sudo beep -f X -l 500
2009-04-01 06:48:48
User: jnash
Functions: awk man sed sudo xargs

Are there any creative pieces of music that can be created using beep and the shell? I'd love to hear it!

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

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:


foo foo A foo

lorem ipsum A lorem

and B.txt will be

bar bar B bar

[[ $(COLUMNS=200 ps faux | awk '/grep/ {next} /ssh -N -R 4444/ {i++} END {print i}') ]] || nohup ssh -N -R 4444:localhost:22 user@relay &
2009-03-31 09:39:59
User: j0rn
Functions: awk nohup ps ssh
Tags: ssh cronjob

I find it ugly & sexy at the same time isn't it ?