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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 tagged sed from sorted by
Terminal - Commands tagged sed - 332 results
sed = <file> | sed 'N;s/\n/\t/'
2009-12-11 14:39:14
User: jgc
Functions: sed
Tags: sed

Print out contents of file with line numbers.

This version will print a number for every line, and separates the numbering from the line with a tab.

grep -oP '"url":"\K[^"]+' $(ls -t ~/.mozilla/firefox/*/sessionstore.js | sed q)
2009-12-09 20:34:32
User: sputnick
Functions: grep ls sed

Require "grep -P" ( pcre ).

If you don't have grep -P, use that :

grep -Eo '"url":"[^"]+' $(ls -t ~/.mozilla/firefox/*/sessionstore.js | sed q) | cut -d'"' -f4
wget -q http://dynamic.xkcd.com/comic/random/ -O-| sed -n '/<img src="http:\/\/imgs.xkcd.com\/comics/{s/.*\(http:.*\)" t.*/\1/;p}' | awk '{system ("wget -q " $1 " -O- | display -title $(basename " $1") -write /tmp/$(basename " $1")");}'
2009-12-09 13:41:25
User: laugg
Functions: awk sed wget
Tags: sed awk wget comic

Only need to install Image Magick package.

Display a xkcd comic with its title and save it in /tmp directory

If you prefer to view the newest xkcd, use this command:

wget -q http://xkcd.com/ -O-| sed -n '/<img src="http:\/\/imgs.xkcd.com\/comics/{s/.*\(http:.*\)" t.*/\1/;p}' | awk '{system ("wget -q " $1 " -O- | display -title $(basename " $1") -write /tmp/$(basename " $1")");}'
find . -type f -exec sed -i s/oldstring/newstring/g {} +
2009-12-09 00:46:13
User: SlimG
Functions: find sed
Tags: sed find

This command find all files in the current dir and subdirs, and replace all occurances of "oldstring" in every file with "newstring".

printf $(echo -n $1 | sed 's/\\/\\\\/g;s/\(%\)\([0-9a-fA-F][0-9a-fA-F]\)/\\x\2/g')
2009-11-25 04:27:39
User: infinull
Functions: echo printf sed

My version uses printf and command substitution ($()) instead of echo -e and xargs, this is a few less chars, but not real substantive difference.

Also supports lowercase hex letters and a backslash (\) will make it through unescaped

awk '/q=/{print $11}' /var/log/httpd/access_log.4 | awk -F 'q=' '{print $2}' | sed 's/+/ /g;s/%22/"/g;s/q=//' | cut -d "&" -f 1
cat /var/log/httpd/access_log | grep q= | awk '{print $11}' | awk -F 'q=' '{print $2}' | sed 's/+/ /g;s/%22/"/g;s/q=//' | cut -d "&" -f 1 | mail youremail@isp.com -s "[your-site] search strings for `date`"
2009-11-22 03:03:06
User: isma
Functions: awk cat grep sed strings

It's not a big line, and it *may not* work for everybody, I guess it depends on the detail of access_log configuration in your httpd.conf. I use it as a prerotate command for logrotate in httpd section so it executes before access_log rotation, everyday at midnight.

awk '{print $1}' "/proc/modules" | xargs modinfo | awk '/^(filename|desc|depends)/'
for f in $(ls *.xml.skippy); do mv $f `echo $f | sed 's|.skippy||'`; done
2009-11-19 21:36:26
User: argherna
Functions: ls mv sed
Tags: sed ls mv for

For this example, all files in the current directory that end in '.xml.skippy' will have the '.skippy' removed from their names.

modinfo $(cut -d' ' -f1 /proc/modules) | sed '/^dep/s/$/\n/; /^file\|^desc\|^dep/!d'
2009-11-18 23:40:46
User: sputnick
Functions: cut modinfo sed

I modify 4077 and marssi commandline to simplify it and skip an error when parsing the first line of lsmod (4077). Also, it's more concise and small now. I skip using xargs ( not required here ). This is only for GNU sed.

For thoses without GNU sed, use that :

modinfo $(lsmod | awk 'NR>1 {print $1}') | sed -e '/^dep/s/$/\n/g' -e '/^file/b' -e '/^desc/b' -e '/^dep/b' -e d
lsmod | sed -e '1d' -e 's/\(\([^ ]*\) \)\{1\}.*/\2/' | xargs modinfo | sed -e '/^dep/s/$/\n/g' -e '/^file/b' -e '/^desc/b' -e '/^dep/b' -e d
2009-11-17 22:51:08
User: marssi
Functions: lsmod modinfo sed xargs

Liked command 4077 so I improved it, by doing all text manipulation with sed.

"Run this as root, it will be helpful to quickly get information about the loaded kernel modules." THX mohan43u

geo(){ curl -s "http://www.geody.com/geoip.php?ip=$(dig +short $1)"| sed '/^IP:/!d;s/<[^>][^>]*>//g'; }
2009-11-12 17:14:09
User: dennisw
Functions: sed

A function that takes a domain name as an argument

egrep -v "^[[:blank:]]*($|#|//|/\*| \*|\*/)" somefile
sed -e '/^[[:blank:]]*#/d; s/[[:blank:]][[:blank:]]*#.*//' -e '/^$/d' -e '/^\/\/.*/d' -e '/^\/\*/d;/^ \* /d;/^ \*\//d' /a/file/with/comments
2009-11-10 17:47:22
Functions: sed
Tags: sed PHP

Strips comments from at least bash and php scripts. Normal # and // as well as php block comments

removes all of the:

empty/blank lines

lines beginning with #

lines beginning with //

lines beginning with /*

lines beginning with a space and then *

lines beginning with */

It also deletes the lines if there's whitespace before any of the above.

Add an alias to use in .bashrc like this:

alias stripcomments="sed -e '/^[[:blank:]]*#/d; s/[[:blank:]][[:blank:]]*#.*//' -e '/^$/d' -e '/^\/\/.*/d' -e '/^\/\*/d;/^ \* /d;/^ \*\//d'"
sed -i '/myexpression/d' /path/to/file.txt
2009-11-09 11:40:45
User: jgc
Functions: sed
Tags: sed regex

The -i option in sed allows in-place editing of the input file.

Replace myexpression with any regular expression.

/expr/d syntax means if the expression matches then delete the line.

You can reverse the functionality to keep matching lines only by using:

sed -i -n '/myexpression/p' /path/to/file.txt
GeoipLookUp(){ curl -A "Mozilla/5.0" -s "http://www.geody.com/geoip.php?ip=$1" | grep "^IP.*$1" | html2text; }
2009-11-06 00:32:27
User: sputnick
Functions: grep
Tags: sed curl

That makes a function you can put in your ~/.bashrc to run it when you need in any term with an IP as argument

sed -n 's/^model name[ \t]*: *//p' /proc/cpuinfo
2009-11-05 10:59:31
User: jgc
Functions: sed
Tags: sed cpuinfo

Alternative command to retrieve the CPU model name and strip off the "model name : " labels.

curl -s "http://www.geody.com/geoip.php?ip=$(curl -s icanhazip.com)" | sed '/^IP:/!d;s/<[^>][^>]*>//g'
2009-11-04 07:15:02
User: getkaizer
Functions: sed
Tags: sed curl

Not my script. Belongs to mathewbauer. Used without his permission.

This script gives a single line as shown in the sample output.

NOTE: I have blanked out the IP address for obvious security reasons. But you will get whatever is your IP if you run the script.

Tested working in bash.

ifconfig eth1 | grep inet\ addr | awk '{print $2}' | cut -d: -f2 | sed s/^/eth1:\ /g
2009-11-03 19:26:40
User: TuxOtaku
Functions: awk cut grep ifconfig sed

Sometimes, you don't really care about all the other information that ifconfig spits at you (however useful it may otherwise be). You just want an IP. This strips out all the crap and gives you exactly what you want.

curl ip.appspot.com
2009-10-31 21:11:10
User: ktoso

Yeah I know it's been up here a million times, but this service is a really clean and nice one. Nothing but your IP address on it. Actually I was to write something like this, and noticed this on appspot... ;)

sed -ne '/^Package: \(.*\)/{s//\1/;h;};/^Installed-Size: \(.*\)/{s//\1/;G;s/\n/ /;p;}' /var/lib/dpkg/status | sort -rn
2009-10-19 19:01:17
User: arcege
Functions: sed sort

Use the hold space to preserve lines until data is needed.

sed -n '/^function h\(\)/,/^}/p' script.sh
2009-10-19 07:55:35
User: haivu
Functions: sed
Tags: bash sed

I often need to extract a function from a bash script and this command will do it.

n=$RANDOM$RANDOM$RANDOM; let "n %= 10000000000"; echo $n
sed -e "$ ! s/$/,/"
2009-10-13 10:13:52
User: jgc
Functions: sed

In this simple example the command will add a comma to the end of every line except the last. I found this really useful when programatically constructing sql scripts. See sample output for example.

echo $RANDOM$RANDOM$RANDOM |cut -c3-12