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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
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2010-09-24 - OAuth and pagination problems fixed
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Commands using head from sorted by
Terminal - Commands using head - 237 results
ran=$(head /dev/urandom | md5sum); MAC=00:07:${ran:0:2}:${ran:3:2}:${ran:5:2}:${ran:7:2}; sudo ifconfig wlan0 down hw ether $MAC; sudo ifconfig wlan0 up; echo ifconfig wlan0:0
2009-07-16 16:21:44
User: workingsmart
Functions: echo head ifconfig sudo

Next time you are leaching off of someone else's wifi use this command before you start your bittorrent ...for legitimate files only of course.

It creates a hexidecimal string using md5sum from the first few lines of /dev/urandom and splices it into the proper MAC address format. Then it changes your MAC and resets your wireless (wlan0:0).

S=`pidof skype`;grep heap /proc/$S/maps|cut -f1 -d' '|awk -F- '{print "0x" $1 " 0x" $2}'|xargs echo "du me t ">l;gdb -batch -p $S -x l>/dev/null 2>&1;strings t|grep \(smirk|head -n1
2009-06-26 20:03:17
User: alvieboy
Functions: awk cut echo grep head xargs

Skype has an internal regex which depicts the emoticons it supports. However you cannot simply search the binary file for it. This small 181 character line will do just that, provided skype is running. And of course, only works in linux.

ls -1t | head -n10
2009-06-23 12:15:12
User: wires
Functions: head ls
Tags: ls

order the files by modification (thanks stanishjohnd) time, one file per output line and filter first 10

for k in `git branch|perl -pe s/^..//`;do echo -e `git show --pretty=format:"%Cgreen%ci %Cblue%cr%Creset" $k|head -n 1`\\t$k;done|sort -r
2009-06-03 08:25:00
User: brunost
Functions: echo head perl sort

Print out list of all branches with last commit date to the branch, including relative time since commit and color coding.

for i in `du --max-depth=1 $HOME | sort -n -r | awk '{print $1 ":" $2}'`; do size=`echo $i | awk -F: '{print $1}'`; dir=`echo $i | awk -F: '{print $NF}'`; size2=$(($size/1024)); echo "$size2 MB used by $dir"; done | head -n 10
lynx -source http://www.commandlinefu.com/commands/random | sed 's/<[^>]*>//g' | head -1037 | tail -10 | sed -e 's/^[ \t]*//' | sed '/^$/d' | head -2
find . -name \*.mp3 -printf "%C+ %h/%f\n" | sort -r | head -n20 | awk '{print "\""$2"\""}' | xargs -I {} cp {} ~/tmp
2009-05-17 07:06:10
User: bkinsey
Functions: awk cp find head sort xargs

Change ~/tmp to the destination directory, such as your mounted media. Change -n20 to whatever number of files to copy. It should quit when media is full. I use this to put my most recently downloaded podcasts onto my phone.

find / \( -name "*.log" -o -name "*.mylogs" \) -exec ls -lrt {} \; | sort -k6,8 | head -n1 | cut -d" " -f8- | tr -d '\n' | xargs -0 rm
2009-05-10 10:45:48
User: ghazz
Functions: cut find head ls sort tr xargs

This works on my ubuntu/debian machines.

I suspect other distros need some tweaking of sort and cut.

I am sure someone could provide a shorter/faster version.

curl -s http://bash.org/?random1|grep -oE "<p class=\"quote\">.*</p>.*</p>"|grep -oE "<p class=\"qt.*?</p>"|sed -e 's/<\/p>/\n/g' -e 's/<p class=\"qt\">//g' -e 's/<p class=\"qt\">//g'|perl -ne 'use HTML::Entities;print decode_entities($_),"\n"'|head -1
2009-05-07 13:13:21
User: Iftah
Functions: grep head perl sed

bash.org is a collection of funny quotes from IRC.

WARNING: some of the quotes contain "adult" jokes... may be embarrassing if your boss sees them...

Thanks to Chen for the idea and initial version!

This script downloads a page with random quotes, filters the html to retrieve just one liners quotes and outputs the first one.

Just barely under the required 255 chars :)


You can replace the head -1 at the end by:

awk 'length($0)>0 {printf( $0 "\n%%\n" )}' > bash_quotes.txt

which will separate the quotes with a "%" and place it in the file.

and then:

strfile bash_quotes.txt

which will make the file ready for the fortune command

and then you can:

fortune bash_quotes.txt

which will give you a random quote from those in the downloaded file.

I download a file periodically and then use the fortune in .bashrc so I see a funny quote every time I open a terminal.

ls /home | head -64 | barcode -t 4x16 | lpr
2009-04-21 22:54:45
User: flux
Functions: head ls
Tags: printing

64 elements max on 16 rows, 4 cols.

GNU Barcode will adapt automagically the width and the eight of your elements to fill the page.

Standard output format is PostScript.

xmms2 mlib search NOT +rating | grep -r '^[0-9]' | sed -r 's/^([0-9]+).*/\1/' | sort -R | head | xargs -L 1 xmms2 addid
2009-04-16 20:27:30
Functions: grep head sed sort xargs

If you're like me and want to keep all your music rated, and you use xmms2, you might like this command.

I takes 10 random songs from your xmms2 library that don't have any rating, and adds them to your current playlist. You can then rate them in another xmms2 client that supports rating (I like kuechenstation).

I'm pretty sure there's a better way to do the grep ... | sed ... part, probably with awk, but I don't know awk, so I'd welcome any suggestions.

echo "12345,12346" |sed -e's/ //'|tr "," "\n"| while read line; do echo -n $line" "; svn log -vr $line https://url/to/svn/repository/|grep "/"|head -1|cut -d"/" -f2; done
/sbin/ifconfig -a | awk '/(cast)/ { print $2 }' | cut -d':' -f2 | head -1
find | sed -e "s/^.*\///" | awk ' BEGIN { FS=""} { print NF " " $0 } ' | sort -nrf | head -10
function jumpTo { xmms2 jump `xmms2 list | grep -i '$1' | head -n 1 | tail -n 1 | sed -re 's@.+\[(.+)/.+\] (.+)@\1@'`; }
2009-04-10 13:43:57
User: pyrho
Functions: grep head sed tail
Tags: xmms2


Declare this function in your Shell, then use it like this:

> jumpTo foo

The script will search for the 'foo' pattern in your current xmms2 playlist (artist or songname), and play the first occurence of it !

< /dev/urandom tr -dc A-Za-z0-9_ | head -c $((1024 * 1024)) | tee >(gzip -c > out.gz) >(bzip2 -c > out.bz) > /dev/null
u=`curl -d 'dl.start=Free' $(curl $1|perl -wpi -e 's/^.*"(http:\/\/rs.*)" method.*$/$1/'|egrep '^http'|head -n1)|grep "Level(3) \#2"|perl -wpi -e 's/^.*(http:\/\/rs[^\\\\]*).*$/$1/'`;sleep 60;wget $u
function headers { head -1 $* | tr ',' '\12' | pr -t -n ; }
2009-03-25 20:07:47
User: totoro
Functions: head pr tr
Tags: CSV headers

This little command (function) shows the CSV header fields (which are field names separated by commas) as an ordered list, clearly showing the fields and their order.

function t { ls -ltch $* | head -20 ; }
2009-03-25 20:05:52
User: totoro
Functions: head ls

Coming back to a project directory after sometime elsewhere?

Need to know what the most recently modified files are?

This little function "t" is one of my most frequent commands.

I have a tcsh alias for it also:

alias t 'ls -ltch \!* | head -20'

head -c $((<pw-lenght>-2)) /dev/urandom | uuencode -m - | sed -e '1d' -e '3d' | sed -e 's/=.*$//g'
2009-03-24 20:05:16
User: P17
Functions: head sed uuencode

Replace < pw-length > with the desired password-length.

The password-length is not always correct, but wayne...

curl -s -u user:password http://twitter.com/statuses/friends_timeline.rss | grep title | sed -ne 's/<\/*title>//gp' | head -n 4 | say -v Bruce
2009-03-20 20:14:13
User: sixtus
Functions: grep head sed

You need curl.. and a Mac of course.

rpm -qa --qf '%{SIZE} %{NAME}\n' | sort -nr | nl | head -6 # six largest RPMs
2009-03-15 22:18:17
User: mpb
Functions: head nl rpm sort

Low on disk space? Check the largest installed RPMs for delete canditates.

vim $( ls -t | head -n1 )
INFILE=/path/to/your/backup.img; MOUNTPT=/mnt/foo; PARTITION=1; mount "$INFILE" "$MOUNTPT" -o loop,offset=$[ `/sbin/sfdisk -d "$INFILE" | grep "start=" | head -n $PARTITION | tail -n1 | sed 's/.*start=[ ]*//' | sed 's/,.*//'` * 512 ]

Suppose you made a backup of your hard disk with dd:

dd if=/dev/sda of=/mnt/disk/backup.img

This command enables you to mount a partition from inside this image, so you can access your files directly.

Substitute PARTITION=1 with the number of the partition you want to mount (returned from sfdisk -d yourfile.img).

ls -t1 | head -n1