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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



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands using head from sorted by
Terminal - Commands using head - 253 results
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)
tr -cd '1-6' < /dev/urandom | head -c 1; echo
2012-09-21 02:16:42
User: atoponce
Functions: head tr

/dev/urandom is cryptographically secure, and indistinguishable from true random, as it gathers data from external sources, influenced by human timing interactions with computers, to fill the entropy pool, and hashes the input with SHA-1. 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.

Change the head(1) count to something other than 5 for more or less numbers.

sudo -s du -sm /Users/* | sort -nr | head -n 10
2012-09-13 10:15:23
User: mematron
Functions: du head sort sudo

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,


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

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

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

for i in {1..10};do wget $(wget -O- -U "" "http://images.google.com/images?imgsz=xxlarge&hl=en&q=wallpaper+HD&start=$(($RANDOM%900+100))" --quiet | grep -oe 'http://[^"]*\.jpg' | head -1);done
2012-07-26 10:42:13
User: dzup
Functions: grep head wget

you may want &hl=en for &hl=es for the language

you may want imgsz=xxlarge for imgsz=large or whatever filter

you may want q=apples or whatever

ip a s eth0 | grep "inet " | head -n 1 | awk '{print $2}' | cut -f1 -d'/'
2012-07-16 07:54:43
User: thelan
Functions: awk cut grep head
Tags: IP

Get the first IPv4 address of an interface

systemctl --failed | head -n -6 | tail -n -1
SEED=$(head -1 /dev/urandom|od -N 1);for i in {1..10};do tmp=$(mkpasswd ${RANDOM});pass=${tmp:2:6};echo Pass $pass Crypt: $(mkpasswd $pass);done
find . -type f -print0 | xargs -0 du -h | sort -hr | head -10
curl -s kernel.org | grep '<strong>' | head -3 | tail -1 | cut -d'>' -f3 | cut -d'<' -f1
ps -e h -o pid --sort -pcpu | head -10 | vzpid -
2012-05-24 14:16:40
User: mrkmg
Functions: head ps
Tags: openvz

This command will list the PID, VEID, and Name of the 10 highest cpu using processes on a openvz host. You must have vzpid installed.

wget -O - http://www.reddit.com/r/wallpapers.rss | grep -Eo 'http://i.imgur.com[^&]+jpg' | head -1 | xargs wget -O background.jpg
2012-04-25 11:15:26
User: untitaker
Functions: grep head wget xargs

Doesn't depend on curl and doesn't use thumbnails as wallpaper (which has the unfortunate effect of only allowing imgur links)

(set -o noglob;while sleep 0.05;do for r in `grep -ao '[[:print:]]' /dev/urandom|head -$((COLUMNS/3))`;do [ $((RANDOM%6)) -le 1 ] && r=\ ;echo -ne "\e[$((RANDOM%7/-6+2));32m $r ";done;echo;done)
2012-04-13 02:09:10
User: khopesh
Functions: echo head set sleep

A tweak using Patola's code as a base, this full-width green matrix display has all the frills (and all the printable characters).

You don't need the surrounding parens if you don't care about losing globbing capabilities. Z-shell (/bin/zsh) needs neither the parens nor the `set -o noglob`

Screen shot (animated): http://desmond.imageshack.us/Himg32/scaled.php?server=32&filename=matrixh.gif&res=landing

If it's too slow, try lowering the `sleep 0.05` or even replacing it with `true` (which is faster than `sleep 0`).

I squashed it as narrow as I could to conserve space, though somebody could probably squeeze a char or two out.


find . -type f -print0 | xargs -0 du -h | sort -hr | head -20
2012-03-30 10:21:12
User: flatcap
Functions: du find head sort xargs

Search for files and list the 20 largest.

find . -type f

gives us a list of file, recursively, starting from here (.)

-print0 | xargs -0 du -h

separate the names of files with NULL characters, so we're not confused by spaces

then xargs run the du command to find their size (in human-readable form -- 64M not 64123456)

| sort -hr

use sort to arrange the list in size order. sort -h knows that 1M is bigger than 9K

| head -20

finally only select the top twenty out of the list

head -n1 nation.tbl | sed 's/\(.\)/\1\n/g' | sort | uniq -c | grep \| | awk '{ print $1 }'
sed -e 's/[;|][[:space:]]*/\n/g' .bash_history | cut --delimiter=' ' --fields=1 | sort | uniq --count | sort --numeric-sort --reverse | head --lines=20
for i in $(ps -eo pid,pmem,pcpu| sort -k 3 -r|grep -v PID|head -10|awk '{print $1}');do diff -yw <(pidstat -p $i|grep -v Linux) <(ps -o euser,pri,psr,pmem,stat -p $i|tail);done
2012-02-16 20:54:32
Functions: awk diff grep head ps sort

It grabs the PID's top resource users with $(ps -eo pid,pmem,pcpu| sort -k 3 -r|grep -v PID|head -10)

The sort -k is sorting by the third field which would be CPU. Change this to 2 and it will sort accordingly.

The rest of the command is just using diff to display the output of 2 commands side-by-side (-y flag) I chose some good ones for ps.

pidstat comes with the sysstat package(sar, mpstat, iostat, pidstat) so if you don't have it, you should.

I might should take off the timestamp... :|

export GREP_COLOR='1;32';while [ true ]; do head -n 100 /dev/urandom; sleep .1; done | hexdump -C | grep --color=auto "ca fe"