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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 - 1,135 results
curl -q -s http://www.hasthelhcdestroyedtheearth.com/ | sed -En '/span/s/.*>(.*)<.*/\1/p'
2015-09-23 23:26:30
User: Tatsh
Functions: sed

Use -q as first argument (as described in `man curl`) to ignore curlrc to ensure the output is always the same regardless of user's configuration.

curl -s http://www.hasthelhcdestroyedtheearth.com/ | sed -En '/span/s/.*>(.*)<.*/\1/p'
2015-09-23 12:30:31
User: BeniBela
Functions: sed

This says if the LHC has destroyed the world. Run it in a loop to monitor the state of Earth. Might not work reliable, if the world has actually been destroyed.

weather() { curl -s "http://www.wunderground.com/q/zmw:$1.1.99999" | grep "og:title" | cut -d\" -f4 | sed 's/&deg;/ degrees F/'; }
pidstat -t | sed 's/,/./4' | awk -v seuil='10.0' '{if (NR>3 && $8>seuil) print }'
last|grep `whoami`|grep -v logged|cut -c61-71|sed -e 's/[()]//g'|awk '{ sub("\\+", ":");split($1,a,":");if(a[3]){print a[1]*60*60+a[2]*60+a[3]} else {print a[1]*60+a[2] }; }'|paste -s -d+ -|bc|awk '{printf "%dh:%dm:%ds\n",$1/(60*60),$1%(60*60)/60,$1%60}'
2015-09-19 03:02:43
User: donjuanica
Functions: awk cut grep last paste sed

Add -n to last command to restrict to last num logins, otherwise it will pull all available history.

sudo apt-get remove --purge $(dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d')
dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d'
curl $1 | grep -E "http.*\.mp3" | sed "s/.*\(http.*\.mp3\).*/\1/" | xargs wget
2015-09-17 13:19:53
User: theodric
Functions: grep sed xargs

The difference between the original version provided and this one is that this one works rather than outputting a wget error

sed -e "s/[^/]*\/\/\([^@]*@\)\?\([^:/]*\).*/\2/"
sed 's/,/\n/g;q' file.csv | nl
2015-08-26 11:38:56
User: flatcap
Functions: sed
Tags: sed nl

Take the header line from a comma-delimited CSV file and enumerate the fields.


First sed replaces all commas with newlines


Then sed quits (q) after the first line.

Finally, nl numbers all the lines

sed -i.$(date +%F@%T) 's/^LogLevel warn/LogLevel debug/g' httpd.conf
2015-07-22 14:47:26
User: zlemini
Functions: date sed

httpd.conf httpd.conf.2015-07-22@14:43:20

diff a.txt b.txt | grep -E '^(<|>)' | sed 's:^< \(.*\):<del style="color\:red; text-decoration\: none">- \1</del><br>:' | sed 's:^> \(.*\):<ins style="color\:green; text-decoration\: none">+ \1</ins><br>:'
xxd -p source | fold -w2 | paste -sd' ' | sed "s/A/B/g" | xxd -p -r > destination
2015-05-26 18:29:48
User: hincor
Functions: fold paste sed
Tags: sed xxd fold paste

Replace all instances of "A" with "B" in file "source" saved as file "destination".

!! IF A/B is multi-byte, then separate bytes with spaces like so: "s/20\ 0A/00/g".

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.

fold -sw 20 <(echo "Long Text to be wrapped with \"\n\"") |sed ':a;N;$!ba;s/ *\n/\\n/g'
2015-04-16 21:06:53
User: alecthegeek
Functions: echo fold sed

I used this fragment with Imagemagick convert so that I can place long text strings in pictures. The "\n" gets converted to a true newline in the image.

So this fragment uses fold command to wrap the line and then sed to convert newlines (and any trailing spaces on the line) to the text "\n"

find /PATHNAME -type l | while read nullsymlink ; do wrongpath=$(readlink "$nullsymlink") ; right=$(echo "$wrongpath" | sed s'|OLD_STRING|NEW_STRING|') ; ln -fs "$right" "$nullsymlink" ; done
2015-04-14 14:58:41
User: iDudo
Functions: echo find ln read readlink sed

After you run this script, you can check status for broken symlink with this command:

find -L . -type l

curl -s http://host.net/url.html | grep magnet | sed -r 's/.*(magnet:[^"]*).*/\1/g'
function every() { sed -n -e "${2}q" -e "0~${1}p" ${3:-/dev/stdin}; }
2015-04-03 01:30:36
User: flatcap
Functions: sed

Thanks to knoppix5 for the idea :-)

Print selected lines from a file or the output of a command.


every NTH MAX [FILE]

Print every NTH line (from the first MAX lines) of FILE.

If FILE is omitted, stdin is used.

The command simply passes the input to a sed script:

sed -n -e "${2}q" -e "0~${1}p" ${3:-/dev/stdin}

print no output

sed -n

quit after this many lines (controlled by the second parameter)

-e "${2}q"

print every NTH line (controlled by the first parameter)

-e "0~${1}p"

take input from $3 (if it exists) otherwise use /dev/stdin

function every() { N=$1; S=1; [ "${N:0:1}" = '-' ] && N="${N:1}" || S=0; sed -n "$S~${N}p"; }
2015-03-21 23:44:59
User: flatcap
Functions: sed

Sometimes commands give you too much feedback.

Perhaps 1/100th might be enough. If so, every() is for you.

my_verbose_command | every 100

will print every 100th line of output.

Specifically, it will print lines 100, 200, 300, etc

If you use a negative argument it will print the *first* of a block,

my_verbose_command | every -100

It will print lines 1, 101, 201, 301, etc

The function wraps up this useful sed snippet:

... | sed -n '0~100p'

don't print anything by default

sed -n

starting at line 0, then every hundred lines ( ~100 ) print.


There's also some bash magic to test if the number is negative:

we want character 0, length 1, of variable N.


If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

grep -xFf <(groups user1|cut -f3- -d\ |sed 's/ /\n/g') <(groups user2|cut -f3- -d\ |sed 's/ /\n/g')
sed -n '/url/s#^.*url=\(.*://.*\)#\1#p' ~/.mozilla/firefox/*.[dD]efault/SDBackups/*.speeddial | sort | uniq
2015-02-17 20:56:28
User: return13
Functions: sed sort

For all users of https://addons.mozilla.org/de/firefox/addon/speed-dial/

git branch | grep -v "master" | sed 's/^[ *]*//' | sed 's/^/git branch -D /' | bash
2015-01-31 00:29:32
User: Trindaz
Functions: grep sed
Tags: git

Delete all your branches except master (useful after archiving branches)

git branch | grep -v "master" | sed 's/^[ *]*//' | sed 's/.*/& &/' | sed 's/^/git tag archive\//' | bash
2015-01-31 00:26:15
User: Trindaz
Functions: grep sed
Tags: git archive

Description by segments delimited by pipe (|)

1. List all git branches

2. Exclude master

3. Trim output and remove display elements such as * next to current branch

4. Repeat branch name after a space (output on each line: branch_name branch_name)

5. Prepend each line with the git tag command

6. Execute the output with bash

ls -l /dev/disk/by-id |grep -v "wwn-" |egrep "[a-zA-Z]{3}$" |sed 's/\.\.\/\.\.\///' |sed -E 's/.*[0-9]{2}:[0-9]{2}\s//' |sed -E 's/->\ //' |sort -k2 |awk '{print $2,$1}' |sed 's/\s/\t/'
2015-01-25 19:29:40
User: lig0n
Functions: awk egrep grep ls sed sort
Tags: zfs disk info

This is much easier to parse and do something else with (eg: automagically create ZFS vols) than anything else I've found. It also helps me keep track of which disks are which, for example, when I want to replace a disk, or image headers in different scenarios. Being able to match a disk to the kernels mapping of said drive the disks serial number is very helpful

ls -l /dev/disk/by-id

Normal `ls` command to list contents of /dev/disk/by-id

grep -v "wwn-"

Perform an inverse search - that is, only output non-matches to the pattern 'wwn-'

egrep "[a-zA-Z]{3}$"

A regex grep, looking for three letters and the end of a line (to filter out fluff)

sed 's/\.\.\/\.\.\///'

Utilize sed (stream editor) to remove all occurrences of "../../"

sed -E 's/.*[0-9]{2}:[0-9]{2}\s//'

Strip out all user and permission fluff. The -E option lets us use extended (modern) regex notation (larger control set)

sed -E 's/->\ //'

Strip out ascii arrows "-> "

sort -k2

Sort the resulting information alphabetically, on column 2 (the disk letters)

awk '{print $2,$1}'

Swap the order of the columns so it's easier to read/utilize output from

sed 's/\s/\t/'

Replace the space between the two columns with a tab character, making the output more friendly

For large ZFS pools, this made creating my vdevs immeasurably easy. By keeping track of which disks were in which slot (spreadsheet) via their serial numbers, I was able to then create my vols simply by copying and pasting the full output of the disk (not the letter) and pasting it into my command. Thereby allowing me to know exactly which disk, in which slot, was going into the vdev. Example command below.

zpool create tank raidz2 -o ashift=12 ata-... ata-... ata-... ata-... ata-... ata-...
hexdump -n6 -e '/1 ":%02X"' /dev/random|sed s/^://g
2015-01-19 03:09:43
User: rubo77
Functions: hexdump sed

Generate a random MAC address with capital letters