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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 replace from sorted by
Terminal - Commands tagged replace - 23 results
while(1){while((date -f ss)%10-gt0){sleep -m 300} echo "$(date -u %s) $((curl|%{$_ -replace '\D+\n',''})">>modemlog.txt;sleep 1;echo .}
2015-12-24 02:12:10
User: omap7777
Functions: date echo sleep

IMPORTANT: You need Windows PowerShell to run this command - in your Windows Command Prompt, type


Create a log file of your Motorola Surfboard SB6141 downstream signal strengths.

Uses the built-in curl to request signal strength data from your SB6141 cable modem.

HTML page has the signal strength numbers for the 8 downstreams.

Some HTML/DOM processing parses out the 8 values from the above page.

The eight extracted signal strengths are then logged to a file.

A small while-loop watches the clock & repeats the process every 10 seconds.

find <mydir> -type f -exec rename 's/<string1>/<string2>/g' {} \;
2015-11-19 17:51:13
User: thrifus
Functions: find rename
Tags: find replace

This version works on OS X (if you have installed `rename`)

for f in `ls`; do sed -i '/MATCHING STRING/ { s/ORIGINAL/REPLACEMENT/; }' ${f} ; done
2015-05-21 19:37:42
User: krizzo
Functions: sed

Find and replace specific characters in a single line in multiple files with sed.

sed -i 's/^.*?].*?:\s//g' skype-chat-log.txt
2014-05-26 07:48:36
Functions: sed

Regular expression search pattern to remove the Datetime and Name when you paste from skype chat into your text editor

From this Gist:


echo "text to prepend" | cat - file
2013-12-18 15:54:17
User: leni536
Functions: cat echo
Tags: cat replace

Prepend text to a file. It doen't need temporary files, ed or sed.

prepend () { array=("$@"); len=${#array[@]}; file=${array[$len-1]}; text=${array[@]:0:$len-1}; printf '%s\n' 0a "$text" . w | ed -s "$file"; }
2013-12-09 21:59:26
User: zlemini
Functions: ed printf
Tags: sed replace


$ prepend content to add [filename]

Uses ed, so no temp files created.

sed -i 's/^/ls -l /' output_files.txt
2013-10-07 15:12:53
User: sonic
Functions: sed
Tags: sed replace

The original command is great, but I often want to prepend to every line.

sed -i "s/\s*/ /g;s/\s*$//" input_file
sed -i "s/\(\x09\{1,\}\)\|\( \{1,\}\)/ /g;s/\(\x09\{1,\}$\)\|\( \{1,\}$\)//g" brisati.txt
2011-12-12 10:24:03
User: knoppix5
Functions: sed

This command does the following:

- converts any sequence of multiple spaces/tabs to one space only

- completely removes any space(s)/tab(s) at the end of each line

(If spaces and tabs are mixed in a sequence i.e. [tab][tab][space][tab], you have to execute this command twice!)

find . -type f | xargs grep -n "Old Text" | tee filesChanged.txt | sed 's/:.*$//' | xargs sed -i 's/Old Text/New Text/g
sed "s/\s\+/;/g;s/^ //;s/ $//" filename.csv
sed -i '1s/^/text to prepend\n/' file1
2011-06-25 12:02:11
User: xeor
Functions: sed
Tags: sed replace

Using the sed -i (inline), you can replace the beginning of the first line of a file without redirecting the output to a temporary location.

2010-09-11 18:51:41
User: mensa13

In case the line you want to join start with a char different than ", you may use \n.*"\n as regex.

:%s/\([^\"]\)\(\n\)/\1 /g
2010-09-03 11:03:49
User: godzillante


this line ends here

but must be concatenated with this one

"this line ends here"

and should NOT be concatenated with this one

grep -ZlRr -e BAD_SCRIPT_LINE * |xargs -0 sed -i 's/BAD_SCRIPT_LINE//g'
2010-08-30 22:12:57
User: homoludens
Functions: grep sed xargs

recursive find and replace. important stuff are grep -Z and zargs -0 which add zero byte after file name so sed can work even with file names with spaces.

cat file_with_tabs.txt | perl -pe 's/\t/ /g'
2010-07-11 13:01:22
User: nikc
Functions: cat perl
Tags: cat perl replace

Replaces tabs in output with spaces. Uses perl since sed seems to work differently across platforms.

sed -i 's/[email protected]/[email protected]/g' `grep [email protected] -rl .`
2010-02-18 18:26:09
User: and3k
Functions: sed

Do a recursive (-r) search with grep for all files where your old mail address is mentioned (-l shows only the file names) and use sed to replace it with your new address. Works with other search/replacement patterns too.

find . -type f |xargs -I% sed -i '/group name/s/>/ deleteMissing="true">/' %
2010-02-01 21:09:57
User: 4fthawaiian
Functions: find sed xargs

Changed out the for loop for an xargs. It's a tad shorter, and a tad cleaner.

for i in `find . -type f`; do sed -i '/group name/s/>/ deleteMissing="true">/' $i; done
2010-02-01 17:16:37
User: allrightname
Functions: sed

Recursively replace a string in files with lines matching string. Lines with the string "group name" will have the first > character replaced while other > characters on other lines will be ignored.

echo -e "swap=me\n1=2"|sed 's/\(.*\)=\(.*\)/\2=\1/g'
$rpl -R oldstring newstring folder
2009-12-09 03:15:31
User: johnraff
Tags: unix replace

If you can install rpl it's simpler to use and faster than combinations of find, grep and sed.

See man rpl for various options.

time on above operation: real 0m0.862s, user 0m0.548s, sys 0m0.180s

using find + sed: real 0m3.546s, user 0m1.752s, sys 0m1.580s

mate - `find * -type f -regex 'REGEX_A' | grep -v -E 'REGEX_B'`
2009-08-12 22:24:08
User: irae
Functions: grep

This does the following:

1 - Search recursively for files whose names match REGEX_A

2 - From this list exclude files whose names match REGEX_B

3 - Open this as a group in textmate (in the sidebar)

And now you can use Command+Shift+F to use textmate own find and replace on this particular group of files.

For advanced regex in the first expression you can use -regextype posix-egrep like this:

mate - `find * -type f -regextype posix-egrep -regex 'REGEX_A' | grep -v -E 'REGEX_B'`

Warning: this is not ment to open files or folders with space os special characters in the filename. If anyone knows a solution to that, tell me so I can fix the line.

for files in $(ls -A directory_name); do sed 's/search/replaced/g' $files > $files.new && mv $files.new $files; done;
2009-05-07 20:13:07
User: bassu
Functions: ls mv sed

Yeah, there are many ways to do that.

Doing with sed by using a for loop is my favourite, because these are two basic things in all *nix environments. Sed by default does not allow to save the output in the same files so we'll use mv to do that in batch along with the sed.