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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 echo from sorted by
Terminal - Commands using echo - 1,329 results
a="www.commandlinefu.com";b="/index.php";for n in $(seq 1 7);do echo -en "GET $b HTTP/1.0\r\nHost: "$a"\r\n\r\n" |nc $a 80 2>&1 |grep Set-Cookie;done
2010-01-28 14:19:43
User: vlan7
Functions: echo grep seq
Tags: bash cookies

The loop is to compare cookies. You can remove it...

Maybe you wanna use curl...

curl www.commandlinefu.com/index.php -s0 -I | grep "Set-Cookie"
echo $(( $( cat count.txt | tr "\n" "+" | xargs -I{} echo {} 0 ) ))
2010-01-27 10:02:30
User: glaudiston
Functions: cat echo tr xargs

if you, like me, do not have the numsum, this way can do the same.

for host in $(cat ftps.txt) ; do if echo -en "o $host 21\nquit\n" |telnet 2>/dev/null |grep -v 'Connected to' >/dev/null; then echo -en "FTP $host KO\n"; fi done
2010-01-26 15:34:18
User: vlan7
Functions: cat echo grep host telnet

I must monitorize a couple of ftp servers every morning WITHOUT a port-scanner

Instead of ftp'ing on 100 ftp servers manually to test their status I use this loop.

It might be adaptable to other services, however it may require a 'logout' string instead of 'quit'.

The file ftps.txt contains the full list of ftp servers to monitorize.

savesIFS=$IFS;IFS=$(echo -en "\n\b"); for items in `ls *.7z`; do 7zr e $items ; done; IFS=$saveIFS
nmap -sP <subnet>.* | egrep -o '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+' > results.txt ; for IP in {1..254} ; do echo "<subnet>.${IP}" ; done >> results.txt ; cat results.txt | sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4 | uniq -u
for i in $(ps -ef | awk '{print $2}') ; { swp=$( awk '/Swap/{sum+=$2} END {print sum}' /proc/$i/smaps ); if [[ -n $swp && 0 != $swp ]] ; then echo -n "\n $swp $i "; cat /proc/$i/cmdline ; fi; } | sort -nr
(IFS=; sed 's/^[]0;[^^G]*^G/^M/g' <SessionLog> | while read -n 1 ITEM; do [ "$ITEM" = "^M" ] && ITEM=$'\n'; echo -ne "$ITEM"; sleep 0.05; done; echo)
2010-01-20 16:11:32
User: jgc
Functions: echo read sed sleep
Tags: read script

This command will play back each keystroke in a session log recorded using the script command. You'll need to replace the ^[ ^G and ^M characters with CTRL-[, CTRL-G and CTRL-M. To do this you need to press CTRL-V CTRL-[ or CTRL-V CTRL-G or CTRL-V CTRL-M.

You can adjust the playback typing speed by modifying the sleep.

If you're not bothered about seeing each keypress then you could just use:

cat session.log
echo $VARIABLE | xargs -d'\40' -n 6 echo
2010-01-20 15:12:53
User: SuperFly
Functions: echo xargs

Print out the contents of $VARIABLE, six words per line, ignoring any single or double quotes in the text. Useful when $VARIABLE contains a sentence that changes periodically, and may or may not contain quoted text.

removedir(){ read -p "Delete the current directory $PWD ? " human;if [ "$human" = "yes" ]; then [ -z "${PWD##*/}" ] && { echo "$PWD not set" >&2;return 1;}; rm -Rf ../"${PWD##*/}"/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }
for /f "delims==" %a in (' dir "%USERPROFILE%\*.sqlite" /s/b ') do echo vacuum;|"sqlite3.exe" "%a"
2010-01-18 20:56:00
User: vutcovici
Functions: dir echo

This command defragment the SQLite databases found in the home folder of the current Windows user.

This is usefull to speed up Firefox startup.

The executable sqlite3.exe must be located in PATH or in the current folder.

In a script use:

for /f "delims==" %%a in (' dir "%USERPROFILE%\*.sqlite" /s/b ') do echo vacuum;|"sqlite3.exe" "%%a"
removedir () { echo "Deleting the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=$(echo "$PWD" | sed 's/ /\\ /g'); foo=$(basename "$blah"); rm -Rf ../$foo/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }
2010-01-17 11:34:38
User: oshazard
Functions: basename cd echo read rm sed


Version 1.1

removedir () { echo "You are about to delete the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=$(echo "$PWD" | sed 's/ /\\ /g'); foo=$(basename "$blah"); rm -Rf ../$foo/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }


Folders with spaces

Version 1.0

removedir () { echo "You are about to delete the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=`basename $PWD`; rm -Rf ../$blah/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }


Hidden directories (.dotdirectory)

Version 0.9

rmdir () { echo "You are about to delete the current directory $PWD. Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=`basename $PWD`; rm -Rf ../$blah/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }

Removes current directory with recursive and force flags plus basic human check. When prompted type yes

1. [[email protected] ~]$ ls

foo bar

2. [[email protected] ~]$ cd foo

3. [[email protected] foo]$ removedir

4. yes

5. rm -Rf foo/

6. [[email protected] ~]$

7. [[email protected] ~]$ ls


echo -e "swap=me\n1=2"|sed 's/\(.*\)=\(.*\)/\2=\1/g'
echo "You can simulate on-screen typing just like in the movies" | pv -qL 10
2010-01-14 20:17:44
User: dennisw
Functions: echo

This will output the characters at 10 per second.

echo 'mkcd() { mkdir -p "$@" && cd "$_"; }' >> ~/.bashrc
2010-01-13 09:37:56
User: phaidros
Functions: cd echo mkdir

combines mkdir and cd

added quotes around $_, thanx to flatcap!

find /lib/modules/`uname -r`/ -type f -iname '*.o' -or -iname '*.ko' |grep -i -o '[a-z0-9]*[-|_]*[0-9a-z]*\.ko$' |xargs -I {} echo '# {}' >>/etc/modules.autoload.d/kernel-2.6
2010-01-13 02:12:08
User: paragao
Functions: echo find grep xargs

Whenever you compile a new kernel, there are always new modules. The best way to make sure you have the correct modules loaded when you boot is to add all your modules in the modules.autoload file (they will be commented) and uncomment all those modules you need.

Also a good way to keep track of the available modules in your system.

For other distros you may have to change the name of the file to /etc/modprobe.conf

for file in $(seq -f '%03.f' 1 $TOTAL ); do echo "($file/$TOTAL)"; curl -f -O http://domain.com/Name_$file.ext; done
2010-01-12 15:23:44
User: nordri
Functions: echo file seq

With counter format [001, 002, ..., 999] , nice with pictures or wallpapers collections.

ps -ef | grep user | awk '{print $2}' | while read pid; do echo $pid ; pfiles $pid| grep portnum; done
2010-01-11 12:34:51
User: sharfah
Functions: awk echo grep ps read

My old Solaris server does not have lsof, so I have to use pfiles.

sudo nmap -F -O | grep "Running: " > /tmp/os; echo "$(cat /tmp/os | grep Linux | wc -l) Linux device(s)"; echo "$(cat /tmp/os | grep Windows | wc -l) Window(s) devices"
2010-01-10 03:09:56
User: matthewbauer
Functions: echo grep sudo

Shows how many Windows and Linux devices are on your network.

May add support for others, but that's all that are on my network right now.

echo -e ${PATH//:/\\n} | less
2010-01-09 23:25:02
User: nicoulaj
Functions: echo
Tags: PATH

Display the $PATH with one line per entry, in a pager.

i=0; for f in $(find ./ -size -10M -exec stat -c %s {} \; ); do i=$(($i + $f)); done; echo $i
for k in `git branch|sed s/^..//`;do echo -e `git log -1 --pretty=format:"%Cgreen%ci %Cblue%cr%Creset" "$k"`\\t"$k";done|sort
echo - | sed -e :a -e 's/^.\{1,50\}$/&-/;ta'
2010-01-06 17:18:15
User: glaudiston
Functions: echo sed

the sed way to print a linhe with 50 hyphens

echo 50 > /proc/sys/vm/swappiness
for i in *.png; do convert "$i" "${i%.png}.jpg" && rm "$i" && echo "$i is converted."; done
2010-01-02 16:26:13
User: auriza
Functions: echo rm

Convert all PNG images in directory to JPEG using ImageMagick, and delete the old PNG images.

echo 'Desktop SPAM!!!' | while read SPAM_OUT; do notify-send "$SPAM_OUT"; done
2009-12-31 15:38:35
User: michelsberg
Functions: echo read
Tags: notify-send

Route output to notify-send to show nice messages on the desktop, e.g. title and interpreter of the current radio stream