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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!

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Commands using head from sorted by
Terminal - Commands using head - 255 results
cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | awk '{h[$1]++}END{for (i in h){print h[i]" "i}}'|sort -nr | cat -n | head -n 30
2010-07-05 06:39:20
User: cp
Functions: awk cat head sort tr


cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | sort -S16M | uniq -c |sort -nr | cat -n | head -n 30

("sort -S1G" - Linux/GNU sort only) will also do the job but as some drawbacks (caused by space/time complexity of sorting) for bigger files...

</dev/urandom tr -dc '[email protected]#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8; echo ""
2010-06-17 19:30:36
User: TexasDex
Functions: echo head tr

Generates a random 8-character password that can be typed using only the left hand on a QWERTY keyboard. Useful to avoid taking your hand off of the mouse, especially if your username is left-handed. Change the 8 to your length of choice, add or remove characters from the list based on your preferences or kezboard layout, etc.

HISTTIMEFORMAT='' history | awk '{a[$2]++}END{for(i in a){print a[i] " " i}}' | sort -rn | head > /tmp/cmds ; gnuplot -persist <<<'plot "/tmp/cmds" using 1:xticlabels(2) with boxes'
2010-06-17 17:38:16
User: narcelio
Functions: awk head sort

This alternative cleans HISTTIMEFORMAT environment variable and calls gnuplot just after /tmp/cmds is closed, to avoid some errors.

history | awk '{a[$2]++}END{for(i in a){print a[i] " " i}}' | sort -rn | head > /tmp/cmds | gnuplot -persist <(echo 'plot "/tmp/cmds" using 1:xticlabels(2) with boxes')
2010-06-13 23:35:13
User: sthrs
Functions: awk echo head sort

Plot your most used commands with gnuplot.

while [ 1 -lt 2 ]; do i=0; COL=$((RANDOM%$(tput cols)));ROW=$((RANDOM%$(tput cols)));while [ $i -lt $COL ]; do tput cup $i $ROW;echo -e "\033[1;34m" $(cat /dev/urandom | head -1 | cut -c1-1) 2>/dev/null ; i=$(expr $i + 1); done; done
2010-05-28 16:07:56
User: dave1010
Functions: cat cut expr head tput

Same as original, but works in bash

while :; do integer i=0; COL=$((RANDOM%$(tput cols))); ROW=$((RANDOM%$(tput cols))); while (( i <= COL)) do tput cup $i $ROW; echo "\033[1;34m" $(cat /dev/urandom | head -1 | cut -c1-1) 2>/dev/null; i=$(expr $i + 1); done done
finger @www.linuxbanks.cn | grep -oE '([[:digit:]]{1,3}\.){3}[[:digit:]]{1,3}' | head -n1
2010-05-05 14:58:55
User: zhangweiwu
Functions: finger grep head
Tags: ip address

This is useful when you got a reserved IP address like and want to find out what IP address is used to access the Internet. You have to know a server with 'efingerd -n' configured, like www.linuxbanks.cn as above.

Other method to find out this information are for example access www.tell-my-ip.com and grep the output. The finger method have the advantage that it is easy to deploy a service like www.tell-my-ip.com, as you only need to get efingerd installed.

date +%s | sha256sum | base64 | head -c <length>; echo
/sbin/ifconfig|grep -B 1 inet |head -1 | awk '{print $5}'
cut -d\ -f 1 ~/.bash_history | sort | uniq -c | sort -rn | head -n 10 | sed 's/.*/ &/g'
curl http://www.reddit.com/r/wallpapers.rss | grep -Eo 'http:[^&]+jpg' | head -1 | xargs feh --bg-seamless
2010-03-27 00:08:40
Functions: grep head xargs

You'll need "feh" to set the background from the commandline. Install with "apt-get install feh"

Thanks to the Redditors on this thread: http://www.reddit.com/r/linux/comments/bira4/is_there_a_linux_version_of_this_preferably_a/

pronounce(){ wget -qO- $(wget -qO- "http://dictionary.reference.com/browse/[email protected]" | grep 'soundUrl' | head -n 1 | sed 's|.*soundUrl=\([^&]*\)&.*|\1|' | sed 's/%3A/:/g;s/%2F/\//g') | mpg123 -; }
alias busy='my_file=$(find /usr/include -type f | sort -R | head -n 1); my_len=$(wc -l $my_file | awk "{print $1}"); let "r = $RANDOM % $my_len" 2>/dev/null; vim +$r $my_file'
2010-03-09 21:48:41
User: busybee
Functions: alias awk find head sort vim wc

This makes an alias for a command named 'busy'. The 'busy' command opens a random file in /usr/include to a random line with vim. Drop this in your .bash_aliases and make sure that file is initialized in your .bashrc.

git log -g --pretty=oneline | grep '}: commit' | awk '{print $1}' | head -1 | xargs git checkout -f
TOTAL_RAM=`free | head -n 2 | tail -n 1 | awk '{ print $2 }'`; PROC_RSS=`ps axo rss,comm | grep [h]ttpd | awk '{ TOTAL += $1 } END { print TOTAL }'`; PROC_PCT=`echo "scale=4; ( $PROC_RSS/$TOTAL_RAM ) * 100" | bc`; echo "RAM Used by HTTP: $PROC_PCT%"
2010-02-26 20:29:45
User: d34dh0r53
Functions: awk echo grep head tail

Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.

newest () { DIR=${1:-'.'}; CANDIDATE=`find $DIR -type f|head -n1`; while [[ ! -z $CANDIDATE ]]; do BEST=$CANDIDATE; CANDIDATE=`find $DIR -newer "$BEST" -type f|head -n1`; done; echo "$BEST"; }
2010-02-04 12:40:44
User: shadycraig
Functions: echo head

Works recusivley in the specified dir or '.' if none given.

Repeatedly calls 'find' to find a newer file, when no newer files exist you have the newest.

In this case 'newest' means most recently modified. To find the most recently created change -newer to -cnewer.

du -s * | sort -nr | head | cut -f2 | parallel -k du -sh
2010-01-28 12:59:14
Functions: cut du head sort
Tags: du xargs parallel

If a directory name contains space xargs will do the wrong thing. Parallel https://savannah.nongnu.org/projects/parallel/ deals better with that.

paste -d "." <(curl http://.../dist.female.first http://.../dist.male.first | cut -d " " -f 1 | sort -uR) <(curl http://..../dist.all.last | cut -d " " -f 1 | sort -R | head -5163) | tr "[:upper:]" "[:lower:]" | sed 's/$/@test.domain/g'
2010-01-21 19:52:28
User: connorsy
Functions: cut head paste sed sort tr

** Replace the ... in URLS with:


Couldn't fit in 256

Created on Ubuntu 9.10 but nothing out of the ordinary, should work anywhere with a little tweaking. 5163 is the number of unique first names you get when combine the male and female first name files from. http://www.census.gov/genealogy/www/data/1990surnames/names_files.html

ifconfig | grep -B 1 "inet addr:" | head -1 | cut -d" " -f1
2010-01-04 23:02:57
User: jasonwalsh
Functions: cut grep head ifconfig

Get the line containing "inet addr:" and the line before that, get down to only the first line, and then get the first word on that line, which should be the interface.

tr -dc 'a-zA-Z0-9' < /dev/urandom | head -c10
2009-12-01 14:22:20
User: Phil
Functions: head tr

A slightly shorter version. Also doesn't put a return character at the end of the password

cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot
2009-11-20 14:53:26
User: taliver
Functions: awk cat head printf sort tr uniq

Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files.

mkpasswd() { head -c $(($1)) /dev/urandom | uuencode - | sed -n 's/.//;2s/\(.\{'$1'\}\).*/\1/p' ;}
2009-11-19 14:27:52
User: taliver
Functions: head sed uuencode

This uses urandom to produce a random password. The random values are uuencoded to ensure only printable characters. This only works for a number of characters between 1 and 60.

for i in *.avi; do echo -n "$i:";mediainfo $i|head | grep PlayTime | cut -d: -f2 ; done | sort -t: -k2 -r
2009-11-09 12:42:20
User: yooreck
Functions: cut echo grep head sort

Similar but using mediainfo instead of totem-something

ps -eo pcpu,user,pid,cmd | sort -r | head -5
shuf -i 1-49 | head -n6 | sort -n| xargs
2009-10-22 12:54:08
User: ioggstream
Functions: head sort

note the xargs at the end