Hide

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.


If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/

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.

Hide

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:

Hide

News

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
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.
Hide

Tags

Hide

Functions

Commands using head from sorted by
Terminal - Commands using head - 242 results
awk '/Dec\/2012/ {print $1,$8}' logfile | grep -ivE '(.gif|.jpg|.png|favicon|.css|.js|robots.txt|wp-l|wp-term)' | sort | uniq -c | sort -rn | head -n 20
rpm -qa --queryformat '%{size} %{name}-%{version}-%{release}\n' | sort -k 1,1 -rn | nl | head -16
2013-03-19 21:10:54
User: mpb
Functions: head nl rpm sort
1

Interesting to see which packages are larger than the kernel package.

Useful to understand which RPMs might be candidates to remove if drive space is restricted.

find . -type f -exec ls -s {} \; | sort -n -r | head -5
tr -dc 'A-Za-z0-9!@#$%^&*' < /dev/urandom | fold -w 12 | head -n 1
xxd -p /dev/urandom |fold -60|head -30|sed 's/\(..\)/\1 /g'
2013-02-19 22:18:52
User: psifertex
Functions: fold head sed
1

Replaces hexdump with the more succint xxd, and the sed was unnecessarily complex.

hexdump -v -e '"%u"' </dev/urandom|fold -60|head -n 30|sed 's/\(.\{2\}\)/\1 /g'
2013-02-16 12:56:24
User: knoppix5
Functions: fold head hexdump sed
6

or

od /dev/urandom -w60 -An|sed 's/ ..../ /g'|head -n 30

(this one lacks digits 8 and 9)

finger `whoami` | awk -F: '{ print $3 }' | head -n1 | sed 's/^ //'
48 function gbl() { git for-each-ref --sort=-committerdate --format='%(committerdate) %(authorname) %(refname)' refs/remotes/origin/|grep -e ".$@"|head -n 10; }
du . | sort -nr | awk '{split("KB MB GB TB", arr); idx=1; while ( $1 > 1024 ) { $1/=1024; idx++} printf "%10.2f",$1; print " " arr[idx] "\t" $2}' | head -25
2012-12-03 02:59:13
User: agas
Functions: awk du head printf sort
0

Lists the size in human readable form and lists the top 25 biggest directories/files

seq 10| shuf | head -1
2012-11-21 03:57:02
Functions: head seq
0

Above command will generate a random number between 1 to 10.

cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 18 | head -1 | python -c "import sys,crypt; stdin=sys.stdin.readline().rstrip('\n'); print stdin;print crypt.crypt(stdin)"
2012-11-09 00:40:22
User: cnyg
Functions: cat fold head python tr
1

Generate a 18 character password from character set a-zA-Z0-9 from /dev/urandom, pipe the output to Python which prints the password on standard out and in crypt sha512 form.

for k in `git branch -r|awk '{print $1}'`;do echo -e `git show --pretty=format:"%Cgreen%ci_%C(blue)%c r_%Cred%cn_%Creset" $k|head -n 1`$k;done|sort -r|awk -F"_" '{printf("%s %17s %-22s %s\n",$1,$2,$3,$4)}'
tr -dc '[:graph:]' </dev/urandom | head -c30; echo
head -c7 /dev/urandom|base64|tr -d '='
tr -dc A-Za-z0-9_ < /dev/urandom | head -c 10 | xargs
ps axo %mem,pid,euser,cmd | sort -nr | head -n 10
echo $(</dev/urandom tr -dc 1-6 | head -c1)
echo $((0x$(head -c5 /dev/random|xxd -ps)%6+1))
2012-09-21 02:16:42
User: atoponce
Functions: echo head
9

/dev/random is said to by cryptographically secure, and unpredictable, as it gathers data from external sources, influenced by human timing interactions with computers, to fill the entropy pool. As such, this is a quick way to do a true random fair-6 dice roll. Using this method, you could easily create passphrases with Diceware http://diceware.com.

for i in {1..5}; do echo -n $((0x$(head -c5 /dev/random|xxd -ps)%6+1)); done; echo
sudo -s du -sm /Users/* | sort -nr | head -n 10
2012-09-13 10:15:23
User: mematron
Functions: du head sort sudo
0

In OSX you would have to make sure that you "sudo -s" your way to happiness since it will give a few "Permission denied" errors before finally spitting out the results. In OSX the directory structure has to start with the "Users" Directory then it will recursively perform the operation.

Your Lord and master,

Mematron

du -sh /home/*|sort -rh|head -n 10
2012-09-12 11:54:06
User: toaster
Functions: du head sort
0

the -h option of du and sort (on appropriate distrib) makes output "Human" readable and still sorted by "reversed size" (sort -rh)

du -sm /home/* | sort -nr | head -n 10
find . -type f | xargs -I% bash -c 'echo -e "\033[31m%\033[0m" && [[ ! `file %` =~ .*binary.* ]] && head "%"'
wget --no-use-server-timestamps $(curl $(curl http://wallbase.cc/random/23/eqeq/1920x1080/0/100/20 | grep 'wallpaper/' | awk -F'"' '{print $2}' | head -n1) | grep -A4 bigwall | grep img | awk -F'"' '{print $2}'); feh --bg-center $(ls -1t | head -n1)
vlc $(for f in /proc/$(pgrep -f libflashplayer.so |head -n 1)/fd/*; do ;if $(file ${f} |grep -q "broken symbolic link to \`/tmp/FlashXX"); then echo ${f};fi;done)
find . -type f -exec ls -shS {} + | head -10
2012-07-28 17:21:46
User: erichamion
Functions: find head ls
0

This requires a version of GNU find that supports the -exec {} + action, but it seems more straightforward than the versions already posted.