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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 tagged sed from sorted by
Terminal - Commands tagged sed - 340 results
perl -i'.bak' -pe 's/old/new/g' <filename>
for file in <filename>; do cp $file{,.bak} && sed 's/old/new/g' $file.bak > $file; done
2009-08-25 16:19:45
User: Cenobite
Functions: cp file sed
Tags: bash sed

"&&" runs sed if and only if the backup completed and /bin/cp exited cleanly. Works for multiple files; just specify multiple filenames (or glob). Use -v switch for cp to play it safe.

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

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.

dd if=/dev/urandom count=200 bs=1 2>/dev/null | tr "\n" " " | sed 's/[^a-zA-Z0-9]//g' | cut -c-16
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.

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.

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

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.

echo -e "HEAD / HTTP/1.1\nHost: slashdot.org\n\n" | nc slashdot.org 80 | head -n5 | tail -1 | cut -f2 -d-
lynx -head -dump http://slashdot.org|egrep 'Bender|Fry'|sed 's/X-//'
sed '/^#.*DEBUG.*/ s/^#//' $FILE
sed -i 's/^.*DEBUG.*/#&/' $file
sed -n 's/.*<foo>\([^<]*\)<\/foo>.*/\1/p'
2009-07-23 07:59:30
User: recursiverse
Functions: sed

Limited, but useful construct to extract text embedded in XML tags. This will only work if bar is all on one line.

If nobody posts an alternative for the multiline sed version, I'll figure it out later...

(cd /source/dir ; tar cv .)|(cd /dest/dir ; tar xv)
2009-07-19 10:31:13
User: marssi
Functions: cd tar

the f is for file and - stdout, This way little shorter.

I Like copy-directory function It does the job but looks like SH**, and this doesn't understand folders with whitespaces and can only handle full path, but otherwise fine,

function copy-directory () { ; FrDir="$(echo $1 | sed 's:/: :g' | awk '/ / {print $NF}')" ; SiZe="$(du -sb $1 | awk '{print $1}')" ; (cd $1 ; cd .. ; tar c $FrDir/ )|pv -s $SiZe|(cd $2 ; tar x ) ; }

infile=$1 for i in $(cat $infile) do echo $i | tr "," "\n" | sort -n | tr "\n" "," | sed "s/,$//" echo done
2009-07-12 21:23:37
User: iframe
Functions: cat echo sed sort tr
Tags: cat bash sort sed tr

Save the script as: sort_file

Usage: sort_file < sort_me.csv > out_file.csv

This script was originally posted by Admiral Beotch in LinuxQuestions.org on the Linux-Software forum.

I modified this script to make it more portable.

for i in *;do mv "$i" "$(echo $i | sed s/PROBLEM/FIX/g)";done
2009-06-28 01:50:25
User: AlecSchueler
Functions: mv

Useful if non-ascii characters in filenames have been improperly encoded. Replace "PROBLEM" with the incorrect characters (e.g. 'é'), and "FIX" with the correct ones (e.g. '?').

sed -n '/START/,${/STOP/q;p}'
2009-06-19 15:27:36
User: mungewell
Functions: sed
Tags: sed grep

GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made.

In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start').

My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater.

dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d'
2009-06-19 10:23:38
User: plasticdoc
Functions: sed
Tags: Linux sed dpkg

will show:

installed linux headers, image, or modules: /^ii/!d

avoiding current kernel: /'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d

only application names: s/^[^ ]* [^ ]* \([^ ]*\).*/\1/

avoiding stuff without a version number: /[0-9]/!d

dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d' | xargs sudo apt-get -y purge
2009-06-19 10:11:00
User: plasticdoc
Functions: sed sudo xargs

will purge:

only installed apps: /^ii/!d

avoiding current kernel stuff: /'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d

using app names: s/^[^ ]* [^ ]* \([^ ]*\).*/\1/

avoiding stuff without a version number: /[0-9]/!d

(Command too long..See sample Output..)
2009-06-14 20:34:37
User: mohan43u
Tags: bash sed echo tr od

curl doesn't provide url-encoding for 'GET' data, it have an option '--data-urlencode', but its only for 'POST' data. Thats why I need to write down this commandline. With 'perl', 'php' and 'python', this is one liner, but just I wrote it for fun. Works in Ubuntu, will work in all linux varients(I hope it will work in unix varients also).

sed '/MARKER/{N;s/THIS/THAT/}'
2009-06-12 02:29:50
User: mungewell
Functions: sed
Tags: sed gnuplot

I've been auto-generating some complex GnuPlots; with multiplots the first plot of each group needs to be a 'plot' whereas the others need to be 'replots' to allow overplotting/autoscaling/etc to work properly.

This is used to replace only the first instance of 'replot'.

lynx -source http://www.commandlinefu.com/commands/random | sed 's/<[^>]*>//g' | head -1037 | tail -10 | sed -e 's/^[ \t]*//' | sed '/^$/d' | head -2
sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e
2009-05-25 05:37:44
User: mohan43u
Functions: echo sed xargs
echo "http%3A%2F%2Fwww.google.com" | sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e


Works under bash on linux. just alter the '-e' option to its corresponding equivalence in your system to execute escape characters correctly.