What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

UpGuard checks and validates configurations for every major OS, network device, and cloud provider.

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:



May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

Top Tags



Commands tagged awk from sorted by
Terminal - Commands tagged awk - 303 results
TZ=GMT date -d "1970/01/01 00:29:36" +%s
seq 9 | sed 'H;g' | awk -v RS='' '{for(i=1;i<=NF;i++)printf("%dx%d=%d%s", i, NR, i*NR, i==NR?"\n":"\t")}'
2011-10-22 18:41:09
User: kev
Functions: awk sed seq
Tags: sed awk

seq -s ' ' 1 9 | sed -n ':a;p;s/ *\w$//;h;/^$/t;b a;q' | tac | awk '{for(i=1;i


1x2=2 2x2=4

1x3=3 2x3=6 3x3=9

1x4=4 2x4=8 3x4=12 4x4=16

1x5=5 2x5=10 3x5=15 4x5=20 5x5=25

1x6=6 2x6=12 3x6=18 4x6=24 5x6=30 6x6=36

1x7=7 2x7=14 3x7=21 4x7=28 5x7=35 6x7=42 7x7=49

1x8=8 2x8=16 3x8=24 4x8=32 5x8=40 6x8=48 7x8=56 8x8=64

1x9=9 2x9=18 3x9=27 4x9=36 5x9=45 6x9=54 7x9=63 8x9=72 9x9=81

unzip -l filename.zip |awk '{ if($4 != "Name" && $4 != "----") print $4}'|xargs -t rm -rf {}
2011-10-20 18:54:15
User: hk0i
Functions: awk rm xargs
Tags: awk xargs unzip rm

Sometimes you unzip a file that has no root folder and it spews files all over the place. This will clean up all of those files by deleting them.

curl -u username --silent "https://mail.google.com/mail/feed/atom" | awk 'BEGIN{FS="\n";RS="(</entry>\n)?<entry>"}NR!=1{print "\033[1;31m"$9"\033[0;32m ("$10")\033[0m:\t\033[1;33m"$2"\033[0m"}' | sed -e 's,<[^>]*>,,g' | column -t -s $'\t'
2011-10-15 23:15:52
User: frntn
Functions: awk column sed

Just an alternative with more advanced formating for readability purpose. It now uses colors (too much for me but it's a kind of proof-of-concept), and adjust columns.

lynx -dump http://example.com/ | awk '/http/{print $2}' | sort -u
2011-10-13 09:49:36
User: mathias
Functions: awk sort
Tags: awk lynx

This will get all links from a given URL, remove any duplicates, and output the result.

ping -qc 10 server.tld | awk -F/ '/^rtt/ {print $5}'
2011-10-12 21:07:06
User: atoponce
Functions: awk ping
Tags: awk ping

Quick and dirty one-liner to get the average ping(1) time from a server.

apt-get remove $(dpkg -l | awk "/^ii linux-(image|headers)/ && ! /`uname -r`/ {print \$2}")
2011-10-09 13:58:47
User: _john
Functions: apt awk

since awk was already there one can use it instead of the 2 greps. might not be faster, but fast enough

tail -n +<N> <file> | head -n 1
2011-09-30 08:30:30
User: qweqq
Functions: head tail

Tail is much faster than sed, awk because it doesn't check for regular expressions.

cat ~/.ssh/id_rsa.pub | ssh <REMOTE> "(cat > tmp.pubkey ; mkdir -p .ssh ; touch .ssh/authorized_keys ; sed -i.bak -e '/$(awk '{print $NF}' ~/.ssh/id_rsa.pub)/d' .ssh/authorized_keys; cat tmp.pubkey >> .ssh/authorized_keys; rm tmp.pubkey)"
2011-09-30 07:39:24
User: tamouse
Functions: cat ssh
Tags: ssh awk

This one is a bit more robust -- the remote machine may not have an .ssh directory, and it may not have an authorized_keys file, but if it does already, and you want to replace your ssh public key for some reason, this will work in that case as well, without duplicating the entry.

echo "command lines" | rev | cut -c 2- | rev
2011-09-21 11:27:52
User: ztank1013
Functions: cut echo ping rev
Tags: sed awk cut rev

In case sed and awk are not available you may use this to remove the last character from a string with "rev" and "cut".

tail -f LOGFILE | awk '{system("say \"" $0 "\"");}'
2011-09-16 06:20:06
User: tamouse
Functions: awk tail
Tags: awk tail say

like #9295, but awkish instead of perlish

grep "HTTP/1.1\" 404" access_log | awk '{print $7 } ' | sort | uniq -c | sort -n
shuf /usr/share/dict/words |grep "^[^']\{3,5\}$" |head -n4
2011-08-24 03:43:55
User: menachem
Functions: grep head
Tags: awk xkcd

This does the same thing that the command 'j_melis' submitted, but does it a lot quicker.

That command takes 43 seconds to complete on my system, while the command I submitted takes 6 seconds.

echo $(grep "^[^']\{3,5\}$" /usr/share/dict/words|shuf -n4)
2011-08-23 21:15:18
User: j_melis
Functions: echo grep
Tags: awk xkcd

The improvement of this command over Strawp's original alternative is that you can specify the size of the words, in this particular case words between 3 and 5 character's long. It also excludes words that contain apostrophes, if you'd rather keep those words simply substitue [^'] for .

awk 'BEGIN {srand} /^[a-z]{4,8}$/ {w[i++]=$0} END {while (j++<4) print w[int(rand*i)]}' /usr/share/dict/words
2011-08-18 02:09:42
User: putnamhill
Functions: awk
Tags: awk xkcd

If you do not have shuf or an -R option in sort, you can fall back on awk. This provides maximum portability IMO. The command first collects words from the dictionary that match the criteria - in this case: lower case words with no punctuation that are 4 to 8 characters long. It then prints 4 random entries. I decided to print each word on a separate line to improve readability.

awk -F\" '/^DocumentRoot/{print $2}' $(httpd -V | awk -F\" '/\.conf/{print $2}')
TIME=$( { time redis-cli PING; } 2>&1 ) ; echo $TIME | awk '{print $3}' | sed 's/0m//; s/\.//; s/s//; s/^0.[^[1-9]*//g;'
2011-08-11 19:09:49
User: allrightname
Functions: awk echo sed time

Outputs the real time it takes a Redis ping to run in thousands of a second without any proceeding 0's. Useful for logging or scripted action.

ls *.zip|awk '{$a="zip -fo "$1" FILENAME"; system($a);}'
2011-07-27 10:22:21
User: youkey
Functions: awk ls
Tags: awk zip

- all zips are in current folder

- FILENAME is file name that should be subsitute in all zips (new version of this file is in current folder)

curl -s --compressed http://funnyjunk.com | awk -F'"' '/ '"'"'mainpagetop24h'"'"'/ { print "http://funnyjunk.com"$4 }' | xargs curl -s | grep -o 'ht.*m/pictures/.*\.jpg\|ht.*m/gifs/.*\.gif' | grep "_......_" | uniq | xargs wget
2011-07-21 15:57:21
User: laniner
Functions: awk uniq xargs

If your version of curl does not support the --compressed option, use

curl -s http://funnyjunk.com | gunzip

instead of

curl -s --compressed http://funnyjunk.com
find . -type f -name "*.py" -exec wc -l {} \; | awk '{ SUM += $1} END {print SUM }'
netstat -nt | awk -F":" '{print $2}' | sort | uniq -c
ps -fu userid | awk '/userid/{print $2}' | xargs kill
2011-06-16 12:20:19
User: unxscorob
Functions: awk ps xargs
Tags: awk

to be executed from root. this works well on most commercial unix systems, have not tried on linux systems.

pkill -KILL -u username
2011-06-16 11:40:57
User: SuperFly
Tags: awk grep who

How to force a userid to log out of a Linux host, by killing all processes owned by the user, including login shells:

gpg --refresh-keys
ifconfig | awk '/HWaddr/ { print $1, $5 }'