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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!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands using tr from sorted by
Terminal - Commands using tr - 288 results
svn st -q | cut -c 2- | tr -d ' ' | xargs tar -czvf ../backup.tgz
2011-08-31 10:30:29
User: titus
Functions: cut tar tr xargs

This works more reliable for me ("cut -c 8-" had one more space, so it did not work)

cat dirtyfile.txt | awk '{gsub(/[[:punct:]]/,"")}1' | tr A-Z a-z | sed 's/[0-9]*//g' | sed -e 's/ //g' | strings | tr -cs '[:alpha:]' '\ ' | sed -e 's/ /\n/g' | tr A-Z a-z | sort -u > cleanfile.txt
2011-08-28 01:26:04
User: purehate
Functions: awk cat sed sort strings tr

Using large wordlists is cumbersome. Using password cracking programs with rules such as Hashcat or John the ripper is much more effective. In order to do this many times we need to "clean" a wordlist removing all numbers, special characters, spaces, whitespace and other garbage. This command will covert a entire wordlist to all lowercase with no garbage.

function expand_url() { curl -sI $1 | grep Location: | cut -d " " -f 2 | tr -d "\n" | pbcopy }
2011-08-21 05:30:09
User: gt
Functions: cut grep tr

Expand a URL, aka do a head request, and get the URL. Copy this value to clipboard.

sort -R /usr/share/dict/british | grep -v -m4 ^\{1,10\}$ | tr [:upper:] [:lower:] | tr "\n" " " | tr -d "'s" | xargs -0 echo
2011-08-16 10:11:21
User: takac
Functions: grep sort tr xargs
Tags: tr xkcd

Doesn't use shuf, its much faster with "shuf -n4" instead of sort -R

RANGE=`wc -l /usr/share/dict/words | sed 's/^\([0-9]*\) .*$/\1/'`; for i in {1..4}; do let "N = $RANDOM % $RANGE"; sed -n -e "${N}p" /usr/share/dict/words | tr -d '\n'; done; RANGE=100; let "N = $RANDOM % $RANGE"; echo $N
jot 4 | awk '{ print "wc -l /usr/share/dict/words | awk '"'"'{ print \"echo $[ $RANDOM * $RANDOM % \" $1 \"]\" }'"'"' | bash | awk '"'"'{ print \"sed -n \" $1 \"p /usr/share/dict/words\" }'"'"' | bash" }' | bash | tr -d '\n' | sed 's/$/\n/'
2011-08-16 00:26:56
User: fathwad
Functions: awk bash sed tr
Tags: tr xkcd

So I use OSX and don't have the shuf command. This is what I could come up with.

This command assumes /usr/share/dict/words does not surpass 137,817,948 lines and line selection is NOT uniformly random.

cat /usr/share/dict/words | grep -P ^[a-z].* | grep -v "'s$" | grep -Pv ^.\{1,15\}$ | shuf -n4 | tr '\n' ' ' | sed 's/$/\n/'
2011-08-15 01:03:48
User: bugmenot
Functions: cat grep sed tr
Tags: tr xkcd shuf

The first grep rejects capitalised words since the dict has proper nouns in it that you mightn't want to use. The second grep rejects words with ending in apostrophe s, and the third forces the words to be at least 15 characters long.

svn st | grep '^?' | sed -e 's/\?[[:space:]]*//' | tr '\n' '\0' | xargs -0 svn add
IFS=?" ; for i in * ; do mv -v $i `echo $i|tr ???????????????????\ aaaeeiooAAAEEIOOOcC_` ; done
shuf -n4 /usr/share/dict/words | tr -d '\n'
pi 62999 | tr 0-9 del\ l\!owrH
2011-07-29 22:47:53
User: maurol
Functions: tr
Tags: bash pi

Pi also says hello world!

find src/ -name "*.java" | while read f; do echo -n "$f "; cat "$f" | tr -dc '{}'; echo; done | awk '{ print length($2), $1 }' | sort -n
svn log | tr -d '\n' | sed -E 's/-{2,}/\'$'\n/g' | sed -E 's/ \([^\)]+\)//g' | sed -E 's/^r//' | sed -E "s/[0-9]+ lines?//g" | sort -g
2011-07-15 00:00:03
User: gdevarajan
Functions: sed sort tr

This is a minor variation to cowboy's submission - his script worked great on Ubuntu, but the sed gave issues on osx (which used BSD). Minor tweaks (sed -E instead of sed -r and \'$'\n to handle the new line made it work.

grep -E '<DT><A|<DT><H3' bookmarks.html | sed 's/<DT>//' | sed '/Bookmarks bar/d' | sed 's/ ADD_DATE=\".*\"//g' | sed 's/^[ \t]*//' | tr '<A HREF' '<a href'
2011-05-26 22:21:01
User: chrismccoy
Functions: grep sed tr
Tags: sed grep chrome

chrome only lets you export in html format, with a lot of table junk, this command will just export the titles of the links and the links without all that extra junk

for i in {21..79};do echo -e "\x$i";done | tr " " "\n" | shuf | tr -d "\n"
apt-cache search pidgin* | awk '{print$ 1}' | tr '\n' ' ' | xargs aptitude -y install
2011-04-13 08:01:22
Functions: apt awk tr xargs

Command to install everything on a debian based system with the prefix you indicate.

tr '\0' '\377' < /dev/zero|dd count=$((<bytes>/512))
2011-04-05 14:26:02
User: cfy
Functions: dd tr
Tags: dd tr

the speed is about 500MB/s on my machine.

i think it's fast enough to output not too many bytes.

while a C program may output 1GB per sencond on my machine.

if the size is not the power of 512,you may change the bs and count in dd.

telnet towel.blinkenlights.nl 666 | sed "s/=== The BOFH Excuse Server ===//" | tr -d '\n' && echo
2011-03-31 05:50:57
User: hintss
Functions: sed telnet tr
Tags: telnet BOFH

Gets a BOFH excuse from the BOFH excuse server (towel.blinkenlights.nl port 666), and passes it through sed and tr to get rid of telnet connection stuff.

while :; do OLD=$NEW; NEW=`cat /proc/net/dev | grep eth0 | tr -s ' ' | cut -d' ' -f "3 11"`; echo $NEW $OLD | awk '{printf("\rin: % 9.2g\t\tout: % 9.2g", ($1-$3)/1024, ($2-$4)/1024)}'; sleep 1; done
while [ /bin/true ]; do OLD=$NEW; NEW=`cat /proc/net/dev | grep eth0 | tr -s ' ' | cut -d' ' -f "3 11"`; echo $NEW $OLD | awk '{printf("\rin: % 9.2g\t\tout: % 9.2g", ($1-$3)/1024, ($2-$4)/1024)}'; sleep 1; done
2011-03-22 10:02:23
User: hons
Functions: awk cut echo grep sleep tr

Just a simple way without the need of additional tools. Of course, replace eth0 with your IF.

function rot13 { if [ -r $1 ]; then cat $1 | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; else echo $* | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; fi }
2011-03-18 09:59:41
User: twjolson
Functions: cat echo tr
Tags: Linux unix tr

Will rot 13 whatever parameter follows 'rot13', whether it is a string or a file. Additionally, it will rot 5 each digit in a number

export PATH=$PATH$(find "$PWD" -name '.*' -prune -o -type f -a -perm /u+x -printf ':%h\n' | sort -u | tr -d '\n'); echo $PATH
2011-03-11 19:31:17
User: dexterhu
Functions: echo export find sort tr

(1) don't run twice, or the same folder will occur in $PATH.

(2) otherwise you need to start a new terminal

CLASSPATH=.; export CLASSPATH=$CLASSPATH$(find "$PWD" -name '*.jar' -type f -printf ':%p\n' | sort -u | tr -d '\n'); echo $CLASSPATH
env LC_CTYPE=C tr -dc "a-zA-Z0-9-_\$\?" < /dev/urandom | head -c 10
2011-02-22 17:09:44
User: aerickson
Functions: env head tr



fixes a problem with bad bytes in /dev/urandom on Mac OS X

tr -dc a-z0-9 </dev/urandom | tr 0-8 \ | tr 9 \\n | sed 's/^[ \t]*//' | fmt -u