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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 - 252 results
( apache2ctl -t && service apache2 restart || (l=$(apache2ctl -t 2>&1|head -n1|sed 's/.*line\s\([0-9]*\).*/\1/'); vim +$l $(locate apache2.conf | head -n1)))
2010-11-26 18:12:08
User: cicatriz
Functions: head locate sed vim

Checks the apache configuration syntax, if is OK then restart the service otherwise opens the configuration file with VIM on the line where the configuration fails.

ps ax -L -o pid,tid,psr,pcpu,args | sort -nr -k4| head -15 | cut -c 1-90
find . -type f -newer 201011151300.txt -exec head -1 {} \;
2010-11-15 22:51:13
User: abm2009
Functions: find head

create the "newer than" file by:

touch -t 201011151300 ./201011151300.txt

the format for the time is


head -n 20 <filename> | tail
curl -s -O http://s3.amazonaws.com/alexa-static/top-1m.csv.zip ; unzip -q -o top-1m.csv.zip top-1m.csv ; head -1000 top-1m.csv | cut -d, -f2 | cut -d/ -f1 > topsites.txt
2010-11-01 01:25:53
User: chrismccoy
Functions: cut head
Tags: curl unzip cut

this will dump a list of domains one per line into a text file

atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.tar.gz} && tar xf $1 -C ${1%.tar.gz}; fi ;}
2010-10-16 05:50:32
User: elfreak
Functions: echo grep head mkdir tar wc

This Anti-TarBomb function makes it easy to unpack a .tar.gz without worrying about the possibility that it will "explode" in your current directory. I've usually always created a temporary folder in which I extracted the tarball first, but I got tired of having to reorganize the files afterwards. Just add this function to your .zshrc / .bashrc and use it like this;

atb arch1.tar.gz

and it will create a folder for the extracted files, if they aren't already in a single folder.

This only works for .tar.gz, but it's very easy to edit the function to suit your needs, if you want to extract .tgz, .tar.bz2 or just .tar.

More info about tarbombs at http://www.linfo.org/tarbomb.html

Tested in zsh and bash.

UPDATE: This function works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in zsh (not working in bash):

atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t(ar.gz||ar.bz2||gz||bz||ar)} && tar xf $1 -C ${1%.t(ar.gz||ar.bz2||gz||bz||ar)}; fi ;}

UPDATE2: From the comments; bepaald came with a variant that works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in bash:

atb() {shopt -s extglob ; l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)} && tar xf $1 -C ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)}; fi ; shopt -u extglob}
svn log --stop-on-copy | grep r[0-9] | awk '{print $1}' | sed "s/r//" | sort -n | head -1
curl --silent http://www.dudalibre.com/gnulinuxcounter?lang=en | grep users | head -2 | tail -1 | sed 's/.*<strong>//g' | sed 's/<\/strong>.*//g'
while [ true ]; do head -n 100 /dev/urandom; sleep .1; done | hexdump -C | grep "ca fe"
tr -cd '[:alnum:]' < /dev/urandom | fold -w30 | head -n1
yes '' | head -n100
wget -q $(lynx --dump 'http://geekandpoke.typepad.com/' | grep '\/.a\/' | grep '\-pi' | head -n 1 | awk '{print $2}') -O geekandpoke.jpg
feh --bg-center `ls -U1 |sort -R |head -1`
wget http://forums.dropbox.com && wget $(cat index.html|grep "Latest Forum Build"|cut -d"\"" -f2) && wget $(cat topic.php*|grep "Linux x86:"|cut -d"\"" -f2|sort -r|head -n1) && rm -rf ~/.dropbox* && rm index.html *.php* && tar zxvf dropbox-*.tar.gz -C ~/
LIST="/some/pic/file /another/picture /one/more/pic"; PIC=$(echo $LIST | sed s/"\ "/"\n"/g | shuf | head -1 | sed s/'\/'/'\\\/'/g ); sed -i s/Mrxvt.Pixmap:.*/"Mrxvt.Pixmap:\t$PIC"/ ~/.mrxvtrc
2010-08-23 10:17:42
User: dog
Functions: echo head sed

Simple way of having random mrxvt backgrounds. Add this to your bashrc and change the path names for the pictures.

man $(ls /bin | shuf | head -1)
2010-08-20 23:12:51
Functions: head ls man
Tags: man

I'm not sure why you would want to do this, but this seems a lot simpler (easier to understand) than the version someone submitted using awk.

curl -L -s `curl -s [http://podcast.com/show.rss]` | xmlstarlet sel -t -m "//enclosure[1]" -v "@url" -n | head -n 1` | ssh -t [user]@[host] "mpg123 -"
2010-07-31 00:17:47
User: denzuko
Functions: head ssh

Gets the latest podcast show from from your favorite Podcast. Uses curl and xmlstarlet.

Make sure you change out the items between brackets.

curl -L -s `curl -s http://www.2600.com/oth-broadband.xml` | xmlstarlet sel -t -m "//enclosure[1]" -v "@url" -n | head -n 1` | ssh -t [user]@[host] "mpg123 -"

Ever wanted to stream your favorite podcast across the network, well now you can.

This command will parse the iTunes enabled podcast and stream the latest episode across the network through ssh encryption.

printf $(( echo "obase=16;$(echo $$$(date +%s%N))"|bc; ip link show|sed -n '/eth/ {N; p}'|grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'|head -c 17 )|tr -d [:space:][:punct:] |sed 's/[[:xdigit:]]\{2\}/\\x&/g')|sha1sum|head -c 32; echo
2010-07-14 14:04:53
User: camocrazed
Functions: echo grep head link printf sed tr
Tags: uuid

first off, if you just want a random UUID, here's the actual command to use:


Your chances of finding a duplicate after running this nonstop for a year are about the same as being hit by a meteorite before finishing this sentence

The reason for the command I have is that it's more provably unique than the one that uuidgen creates. uuidgen creates a random one by default, or an unencrypted one based on time and network address if you give it the -t option.

Mine uses the mac address of the ethernet interface, the process id of the caller, and the system time down to nanosecond resolution, which is provably unique over all computers past, present, and future, subject to collisions in the cryptographic hash used, and the uniqueness of your mac address.

Warning: feel free to experiment, but be warned that the stdin of the hash is binary data at that point, which may mess up your terminal if you don't pipe it into something. If it does mess up though, just type

tail -n +4 | head -n 1
head -n X | tail -n 1
2010-07-08 22:06:39
User: infinull
Functions: head tail

using tail first won't do it because tail counts from the bottom of the file. You could do it this way but I don't suggest it

tail -n 4 | head -n 1
2010-07-08 19:50:06
User: puddy
Functions: head tail

tail -n X | head -n 1

prints a specific line, where X is the line number

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 '12345!@#$%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.