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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
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




Commands using sed from sorted by
Terminal - Commands using sed - 1,077 results
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.

seq 1 12 | sed 1,5d ; seq 1 12 | head --lines=-5
2009-08-01 00:41:52
User: flux
Functions: head sed seq
Tags: sed tail HEAD fun

Strangely enough, there is no option --lines=[negative] with tail, like the head's one, so we have to use sed, which is very short and clear, you see.

Strangely more enough, skipping lines at the bottom with sed is not short nor clear. From Sed one liner :

# delete the last 10 lines of a file

$ sed -e :a -e '$d;N;2,10ba' -e 'P;D' # method 1

$ sed -n -e :a -e '1,10!{P;N;D;};N;ba' # method 2

echo $( du -sm /var/log/* | cut -f 1 ) | sed 's/ /+/g'
2009-07-31 21:42:53
User: flux
Functions: cut du echo sed
Tags: echo bc

When you've got a list of numbers each on its row, the ECHO command puts them on a simple line, separated by space. You can then substitute the spaces with an operator. Finally, pipe it to the BC program.

curl -sI http://slashdot.org/ | sed -nr 's/X-(Bender|Fry)(.*)/\1\2/p'
2009-07-31 19:55:17
Functions: sed

I'm pretty sure everyone has curl and sed, but not everyone has lynx.

ps -o rss -C httpd | tail -n +2 | (sed 's/^/x+=/'; echo x) | bc
2009-07-31 15:15:08
Functions: echo ps sed tail

Display the amount of memory used by all the httpd processes. Great in case you are being Slashdoted!

lynx -head -dump http://slashdot.org|egrep 'Bender|Fry'|sed 's/X-//'
echo -e "HEAD / HTTP/1.1\nHost: slashdot.org\n\n" | nc slashdot.org 80 | egrep "Bender|Fry" | sed "s/X-//"
2009-07-30 19:15:07
Functions: echo egrep sed

slashdot.org webserver adds an X-Bender or X-Fry HTTP header to every response!

ls foo*.jpg | awk '{print("mv "$1" "$1)}' | sed 's/foo/bar/2' | /bin/sh
md5sum * | sed 's/^\(\w*\)\s*\(.*\)/\2 \1/' | while read LINE; do mv $LINE; done
sed '/^#.*DEBUG.*/ s/^#//' $FILE
sed -i 's/^.*DEBUG.*/#&/' $file
equery s | sed 's/(\|)/ /g' | sort -n -k 9 | gawk '{print $1" "$9/1048576"m"}'
2009-07-30 01:12:10
User: Alanceil
Functions: gawk sed sort

On a Gentoo system, this command will tell you which packets you have installed and sort them by how much space they consume. Good for finding out space-hogs when tidying up disk space.

ls -pt1 | sed '/.*\//d' | sed 1d | xargs rm
2009-07-29 13:59:58
User: patko
Functions: ls sed xargs

Useful for deleting old unused log files.

ipconfig getpacket en0 | grep yi| sed s."yiaddr = "."en0: ". ipconfig getpacket en1 | grep yi| sed s."yiaddr = "."en1: ".