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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.
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Commands using echo from sorted by
Terminal - Commands using echo - 1,297 results
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. [user@host ~]$ ls

foo bar

2. [user@host ~]$ cd foo

3. [user@host foo]$ removedir

4. yes

5. rm -Rf foo/

6. [user@host ~]$

7. [user@host ~]$ 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

xlaunch(){ T=/tmp/$$;sh -c "$@" >$T.1 2>$T.2;S=$?;[ $S -ne 0 ]&&{ echo -e "'$@' failed with error $S\nSTDERR:\n$(cat $T.2)\nSTDOUT:\n$(cat $T.1)\n"|xmessage -file -;};rm -f $T.1 $T.2;}
2009-12-31 06:59:56
User: bhepple
Functions: echo
Tags: X

When you run an X program from a terminal you can see any errors. But when it's run from another X program (eg from a menu item, from your fluxbox 'keys' file etc) it might just die and you see nothing (except perhaps in .xsession-errors). Instead, launch it via this command and you'll see the termination status, stderr and stdout.

eg: "xlaunch firefox" or "xlaunch 'echo stdout; echo stderr >&2; false'":

'echo stdout; echo stderr >&2; false' failed with error 1





BACKUP_FILE_SIZE=`eval ls -l ${BACKUP_FILE} | awk {'print $5'}`; if [ $BACKUP_FILE_SIZE -le 20 ]; then echo "its empty"; else echo "its not empty"; fi
2009-12-29 08:34:37
User: Redrocket
Functions: awk echo ls

If you gzip an empty file it becomes 20 bytes. Some backup checks i do check to see if the file is greater than zero size (-s flag) but this is no good here. Im sure someone has a better check than me for this? No check to see if file exists before checking it's size.

b(){ echo "scale=${2:-2}; $1" | bc -l; }
2009-12-23 23:44:31
User: dadi
Functions: bc echo

terms inclosing '()' must be enclosed by "" (soft quotes)

bash variables must be referenced: b $x/$y

ugly bracket checking (balanced, fractions...)

default precision 2

DIR=. ; FSTYPE=$(df -TP ${DIR} | grep -v Type | awk '{ print $2 }') ; echo "${FSTYPE}"
2009-12-22 14:01:50
User: unixhome
Functions: awk df echo grep

Exclude 400 client hosts with NFS auto-mounted home directories.

Easily modified for inclusion in your scripts.

echo -ne "\e[32m" ; while true ; do echo -ne "\e[$(($RANDOM % 2 + 1))m" ; tr -c "[:print:]" " " < /dev/urandom | dd count=1 bs=50 2> /dev/null ; done
2009-12-19 19:05:04
User: psykotron
Functions: dd echo tr true
Tags: color

A bit different from some of the other submissions. Has bold and uses all c printable characters. Change the bs=value to speed up and increase the sizes of the bold and non-bold strings.

p() { l=$LINES; case $1 in do) shift; IFS=$'\n' _pg=( $("$@") ) && _pgn=0 && p r;; r) echo "${_pg[*]:_pgn:$((l-4))}";; d) (( _pgn+=l-4 )); (( _pgn=_pgn>=${#_pg[@]}?${#_pg[@]}-l+4:_pgn )); p r;; u) (( _pgn=_pgn<=l-4?0:_pgn-$l-4 )); p r;; esac; }
2009-12-18 23:35:53
User: intuited
Functions: echo
Tags: bash pager

Manpages, command summaries, and pretty much everything else usually have the information you're most likely to want at the beginning. Seeing just the last 40 or so lines of options from a command that has 100 is not super useful, and having to scroll up each time you want to glance at something is spastic.

Run this and then do something like

p do vi --help

and you'll get the first screen(-mostly-)full of vi's usage info and options list

Then use

p d

to page down, and

p u

to page up.

To see the current page again:

p r

Also useful for situations like

p do aptitude search ~dsmorgasbord p next #p sudo aptitude -r install libwickedawesome-perl-snoochieboochies p next p sudo aptitude -r install libwickedawesome-perl-snoochieboochies snazztasticorama-dev-v0.&#8734;

where you're using readline up-arrow, HOME, END, etc., to quickly recall commented commands.

For the unaware, that option to aptitude search will bring up all of the packages whose descriptions contain the string "smorgasbord". Depending on your distro, there could potentially be hundreds of them.

getent shadow | while IFS=: read a b c; do grep -q '!' <<< "$b" && echo "$a LOCKED" || echo "$a not locked"; done
2009-12-18 15:24:19
User: sputnick
Functions: echo getent grep read
man 5 shadow

I think it's more reliable, because

passwd -S

dont show "locked" but "L" as second field on my Archlinux for a particular user.

( unixhome alternative ).

awk -F":" '{ print $1 }' /etc/passwd | while read UU ; do STATUS=$(passwd -S ${UU} | grep locked 2>/dev/null) ; if [[ ! -z ${STATUS} ]] ; then echo "Account ${UU} is locked." ; fi ; done
echo $LS_COLORS | sed 's/:/\n/g' | awk -F= '!/^$/{printf("%s \x1b[%smdemo\x1b[0m\n",$0,$2)}'
2009-12-15 01:17:46
User: bones7456
Functions: awk echo sed

This can show all ls colors, with a demo.