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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 sed from sorted by
Terminal - Commands using sed - 1,140 results
find /dir | awk '{print length, $0}' | sort -nr | sed 's/^[[:digit:]]* //' | while read dirfile; do outfile="$(echo "$(basename "$dirfile")" | unaccent UTF-8)"; mv "$dirfile" "$(dirname "$dirfile")/$outfile"; done
2009-08-24 21:24:18
User: Patola
Functions: awk basename find mv read sed sort

This command changes all filename and directories within a directory tree to unaccented ones. I had to do this to 'sanitize' some samba-exported trees. The reason it works might seem a little difficult to see at first - it first reverses-sort by pathname length, then it renames only the basename of the path. This way it'll always go in the right order to rename everything.

Some notes:

1. You'll have to have the 'unaccent' command. On Ubuntu, just aptitude install unaccent.

2. In this case, the encoding of the tree was UTF-8 - but you might be using another one, just adjust the command to your encoding.

3. The program might spit a few harmless errors saying the files are the same - not to fear.

y=http://www.youtube.com;for i in $(curl -s $f|grep -o "url='$y/watch?v=[^']*'");do d=$(echo $i|sed "s|url\='$y/watch?v=\(.*\)&.*'|\1|");wget -O $d.flv "$y/get_video.php?video_id=$d&t=$(curl -s "$y/watch?v=$d"|sed -n 's/.* "t": "\([^"]*\)",.*/\1/p')";done
2009-08-22 21:31:29
User: matthewbauer
Functions: echo grep sed

This will download a Youtube playlist and mostly anything http://code.google.com/apis/youtube/2.0/reference.html#Video_Feeds

The files will be saved by $id.flv

sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).in-addr.arpa domain name pointer\(.*\)\./\4.\3.\2.\1\5/' \ lookups.txt
2009-08-22 09:37:20
User: hemanth
Functions: sed
Tags: sed

Reverse DNS lookups, from a file with list of IP's, here the file is called lookups.txt

mailq | grep DrWEB | awk {'print $1'} | sed s/*//g | postsuper -d -
for kern in $(grep "initrd " /boot/grub/grub.conf|grep -v ^#|cut -f 2- -d-|sed -e 's/\.img//g'); do mkinitrd -v -f /boot/initrd-$kern.img $kern; done
curl -s http://www.commandlinefu.com/commands/browse|egrep '("Fin.*and"|<div class="command">.*</div>)'|sed 's/<[^<]*>//g'|ruby -rubygems -pe 'require "cgi"; $_=sprintf("\n\n%-100s\n\t#%-20s",CGI.unescapeHTML($_).chomp.strip, gets.lstrip) if $.%2'
2009-08-18 19:04:03
User: copremesis
Functions: egrep sed

just bored here at work ... if your are daring ... add '| bash' .... enjoy

require 'ruby'

eval $(sed -n "s/^d[^D]*DB_\([NUPH]\)[ASO].*',[^']*'\([^']*\)'.*/_\1='\2'/p" wp-config.php) && mysqldump --opt --add-drop-table -u$_U -p$_P -h$_H $_N | gpg -er AskApache >`date +%m%d%y-%H%M.$_N.sqls`
2009-08-18 07:03:08
User: AskApache
Functions: eval gpg sed

The coolest way I've found to backup a wordpress mysql database using encryption, and using local variables created directly from the wp-config.php file so that you don't have to type them- which would allow someone sniffing your terminal or viewing your shell history to see your info.

I use a variation of this for my servers that have hundreds of wordpress installs and databases by using a find command for the wp-config.php file and passing that through xargs to my function.

host -t a dartsclink.com | sed 's/.*has address //'
sed -e :a -e 's/<[^>]*>//g;/</N;//ba' index.html
2009-08-14 09:55:00
User: Blackbit
Functions: sed

This regular expression removes all HTML-Tags from the file.

id="dMH0bHeiRNg";mplayer -fs http://youtube.com/get_video.php?video_id=$id\&t=$(curl -s http://www.youtube.com/watch?v=$id | sed -n 's/.*, "t": "\([^"]*\)", .*/\1/p')
2009-08-13 14:16:01
User: matthewbauer
Functions: id sed

The original doesn't work for me - but this does. I'm guessing that Youtube updated the video page so the original doesn't work.

find $MAILDIR/ -type f -printf '%T@ %p\n' | sort --reverse | sed -e '{ 1,100d; s/[0-9]*\.[0-9]* \(.*\)/\1/g }' | xargs -i sh -c "cat {}&&rm -f {}" | gzip -c >>ARCHIVE.gz
find . -name \*.pdf -exec pdfinfo {} \; | grep Pages | sed -e "s/Pages:\s*//g" | awk '{ sum += $1;} END { print sum; }'
old='apt-get'; new="su-${old}"; command="sudo ${old}"; alias "${new}=${command}"; $( complete | sed -n "s/${old}$/${new}/p" ); alias ${new}; complete -p ${new}
2009-08-10 00:15:05
User: Josay
Functions: alias sed

In Bash, when defining an alias, one usually loses the completion related to the function used in that alias (that completion is usually defined in /etc/bash_completion using the complete builtin).

It's easy to reuse the work done for that completion in order to have smart completion for our alias.

That's what is done by this command line (that's only an example but it may be very easy to reuse).

Note 1 : You can use given command line in a loop "for old in apt-get apt-cache" if you want to define aliases like that for many commands.

Note 2 : You can put the output of the command directly in your .bashrc file (after the ". /etc/bash_completion") to always have the alias and its completion

nslookup commandlinefu.com|sed 's/[^0-9. ]//g'|tail -n 1|awk -F " " '{print $2}'
2009-08-07 17:32:55
User: thundernode
Functions: awk nslookup sed tail

I use this in a script on my openwrt router to check if my DynDNS needs to be updated, saves your account from being banned for blank updates.

dig commandlinefu.com | sed -nr 's/^[^;].*?\s([.0-9]{7,15})$/\1/ p'
2009-08-07 16:11:31
User: birnam
Functions: dig sed

Strips the non-ip information from the dig output. Could be combined with "head -1" to ensure a single ip is returned. Useful for outputting as a variable for use in scripts.

ips(){ for if in ${1:-$(ip link list|grep '^.: '|cut -d\ -f2|cut -d: -f1)};do cur=$(ifconfig $if|grep "inet addr"|sed 's/.*inet addr:\([0-9\.]*\).*/\1/g');printf '%-5s%-15s%-15s\n' $if $cur $(nc -s $cur sine.cluenet.org 128 2>/dev/null||echo $cur);done;}
2009-08-07 10:04:46
User: frozenfire
Functions: cut echo grep ifconfig link sed

Gets the internal and external IP addresses of all your interfaces, or the ones given as arguments

dd if=/dev/urandom count=200 bs=1 2>/dev/null | tr "\n" " " | sed 's/[^a-zA-Z0-9]//g' | cut -c-16
ifconfig $devices | grep "inet addr" | sed 's/.*inet addr:\([0-9\.]*\).*/\1/g'
wget -O - http://checkip.dyndns.org|sed 's/[^0-9.]//g'
curl -s 'http://checkip.dyndns.org' | sed 's/.*Current IP Address: \([0-9\.]*\).*/\1/g'
sed "s:/old/direcory/:/new/directory/:" <file>
2009-08-06 00:37:45
Functions: sed
Tags: sed

Having to escape forwardslashes when using sed can be a pain. However, it's possible to instead of using / as the separator to use : .

I found this by trying to substitute $PWD into my pattern, like so

sed "s/~.*/$PWD/" file.txt

Of course, $PWD will expand to a character string that begins with a / , which will make sed spit out an error such as "sed: -e expression #1, char 8: unknown option to `s'".

So simply changing it to

sed "s:~.*:$PWD:" file.txt

did the trick.

stat -f '%Sp %p %N' * | rev | sed -E 's/^([^[:space:]]+)[[:space:]]([[:digit:]]{4})[^[:space:]]*[[:space:]]([^[:space:]]+)/\1 \2 \3/' | rev
2009-08-04 08:45:20
User: vwal
Functions: rev sed stat

Since the original command (#1873) didn't work on FreeBSD whose stat lacks the "-c" switch, I wrote an alternative that does. This command shows also the fourth digit of octal format permissions which yields the sticky bit information.

printf '\!:1\0\!:1\0\!:2' | mmencode | tr -d '\n' | sed 's/^/AUTH PLAIN /'
2009-08-04 05:04:50
User: vwal
Functions: printf sed tr

I use this as an alias:

alias authplain "printf '\!:1\0\!:1\0\!:2' | mmencode | tr -d '\n' | sed 's/^/AUTH PLAIN /'"


# authplain someuser@somedomain.com secretpassword

AUTH PLAIN c29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac2VjcmV0cGFzc3dvcmQ=


wget `lynx -dump http://www.ebow.com/ebowtube.php | grep .flv$ | sed 's/[[:blank:]]\+[[:digit:]]\+\. //g'`
2009-08-02 14:09:53
User: spaceyjase
Functions: grep sed wget

I wanted all the 'hidden' .flv files from the http link in the command line; wget seemed appropriate, fed with output from lynx, grep the flv files and the normalised via sed (to remove the numeric bullet). Similar to the 'Grab mp3 files' fu. Replace link with your own, grep arg with something more interesting ;) See here for something along the same lines...


Hope you find it useful! Improvements welcome, naturally.

net=DTAG-DIAL ; for (( i=1; i<30; i++ )); do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done
2009-08-01 05:28:19
User: drizzt
Functions: grep sed whois

Useful if you f.i. want to block/allow all connections from a certain provider which uses successive netnames for his ip blocks. In this example I used the german Deutsche Telekom which has DTAG-DIAL followed by a number as netname for the dial in pools.

There are - as always ;) - different ways to do this. If you have seq available you can use

net=DTAG-DIAL ; for i in `seq 1 30`; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done

or without seq you can use bash brace expansion

net=DTAG-DIAL ; for i in {1..30}; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done

or if you like while better than for use something like

net=DTAG-DIAL ; i=1 ; while true ; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; test $i = 30 && break ; i=$(expr $i + 1) ; done

and so on.