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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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Maintained by Jon H.

Site originally by David Winterbottom (user root).

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

All commands from sorted by
Terminal - All commands - 12,387 results
ffmpeg -i [source].avi -f mp4 -vcodec mpeg4 -b 250000 -s 480?320 -acodec aac -ar 24000 -ab 64 -ac 2 [destination].mp4
stty cbreak -echo; KEY=$(dd bs=1 count=1 2>/dev/null); stty -cbreak echo
2009-06-09 13:15:49
User: inof
Functions: dd stty

This shell snippet reads a single keypress from stdin and stores it in the $KEY variable.

You do NOT have to press the enter key!

The key is NOT echoed to stdout!

This is useful for implementing simple text menus in scripts and similar things.

x2vnc {-west|-east|-north|-south} computer-ip:display-number
2009-06-09 12:09:43
User: kellsens

This command use vnc to connect to another computer and emulate an dual-screen enviroment.

Example of use:

x2vnc -west

After this, if vnc server needs an password, will be prompt in the shell.

p.s.: sorry my english

watch -d -n 3 "iw dev wlan0 station dump; iwconfig wlan0"
$command 3>&1 1>&2 2>&3
2009-06-09 08:48:08
User: svg

Possible use, to filter something in stderr:

(/usr/bin/$COMMAND $PARAM 3>&1 1>&2 2>&3 | grep -v $uninteresting_error ) 3>&1 1>&2 2>&3

ncdu directory_name
2009-06-09 00:02:48
User: bwoodacre

ncdu is a text-mode ncurses-based disk usage analyzer. Useful for when you want to see where all your space is going. For a single flat directory it isn't more elaborate than an du|sort or some such thing, but this analyzes all directories below the one you specify so space consumed by files inside subdirectories is taken into account. This way you get the full picture. Features: file deletion, file size or size on disk and refresh as contents change. Homepage: http://dev.yorhel.nl/ncdu

echo "$(( 0x10 )) - $(( 010 )) = $(( 0x10 - 010 ))"
2009-06-08 19:35:53
User: asmoore82
Functions: echo

^Hexadecimal Ten minus Octal Ten is Eight(in Decimal).

echo "$(( 0xaf )) = $(( 0257 ))"

^Hexadecimal AF and Octal 257 are both Decimal 175.

bash -x script.sh 2> log
diff -urp /originaldirectory /modifieddirectory
find . -iname '*.jar' | xargs du -ks | cut -f1 | xargs echo | sed "s/ /+/g" | bc
w3m -dump_head www.fiat.com | awk '/Date+/{print $6, $7}'
2009-06-08 00:06:01
User: m33600
Functions: awk

w3m is a commanline web browser, full of options, I used -dump_head for less unnecessary page download.

With awk, I can retrieve dynamic changes in webpages in this very econnomical fashion

wget $URL | htmldoc --webpage -f "$URL".pdf - ; xpdf "$URL".pdf &
watch '/home/mm/bash/keypress.sh |/home/mm/bash/evento.sh'
2009-06-07 20:57:49
User: m33600
Functions: watch

evento.sh needed for awk syntax

the aplay command makes a camera sound. It takes a picture of who looked at the display


# evento.sh: deteta evento e fala

awk '{print}' | espeak -v pt -stdin

awk '/e/{print "emergencia"}' | espeak -v pt -stdin

aplay -q /home/mm/bash/camera.wav # -q inibe verbose do comand aplay

exit 0

awk '{print}' | espeak -v pt -stdin
2009-06-07 20:45:44
User: m33600
Functions: awk

Speaks whatever comes in via stdin (-v pt = portuguese, default = englisg)

..speech part of keyboard event talker. Made to accomplish a simple alarm central based on a cheap keyboard circuit. This way I have one zone per direct keypress. Depends on keypress.sh. It speaks out loud wich zone (key) has been pressed ( faulted ). Here is keypress.sh :


# keypress.sh: Detect a user keypress ("hot keys").


old_tty_settings=$(stty -g) # Save old settings (why?).

stty -icanon

Keypress=$(head -c1) # or $(dd bs=1 count=1 2> /dev/null)

# on non-GNU systems

aplay -q /home/mm/bash/beep-1.wav


echo "Chamada quarto \""$Keypress"\"."


stty "$old_tty_settings" # Restore old settings.

# Thanks, Stephane Chazelas.

exit 0

( nw=192.168.0 ; h=1; while [ $h -lt 255 ] ; do ( ping -c2 -i 0.2 -W 0.5 -n $nw.$h & ); h=$[ $h + 1 ] ; done ) | awk '/^64 bytes.*/ { gsub( ":","" ); print $4 }' | sort -u
2009-06-07 15:14:46
Functions: awk ping sort

What do you do when nmap is not available and you want to see the hosts responding to an icmp echo request ? This one-liner will print all hosts responding with their ipv4 address.

ls -la | sort -k 5bn
2009-06-07 14:35:17
Functions: ls sort

Sort ls output of all files in current directory in ascending order

Just the 20 biggest ones:

ls -la | sort -k 5bn | tail -n 20

A variant for the current directory tree with subdirectories and pretty columns is:

find . -type f -print0 | xargs -0 ls -la | sort -k 5bn | column -t

And finding the subdirectories consuming the most space with displayed block size 1k:

du -sk ./* | sort -k 1bn | column -t
dd if=/dev/zero of=/dev/sdb bs=446 count=1
2009-06-07 10:29:49
User: dcabanis
Functions: dd
Tags: dd grub boot usb

If you don't want your computer to try to boot form a USB stick that used to be used as a boot device (maybe for a live linux distro), you will have to remove the boot loader from your stick other wise the boot will fail each time the device is attached to your PC.

for f in *.jpg; do exif --ifd=0 --tag=0x0110 --set-value="LOMO LC-A" --output=$f $f; exif --ifd=0 --tag=0x010f --set-value="LOMO" --output=$f $f; done }
2009-06-07 09:05:14
User: beanie

this takes every jpg in the current directory and changes the exif data for manufactur and model. in my case i change it to LOMO LC-A because my scanner puts his data in there :]

find . -type d -exec chmod 755 {} \;
2009-06-07 08:17:06
User: marssi
Functions: chmod find
Tags: find chmod

"find . -type d -print0 | xargs -0 chmod 755"

thanks masterofdisaster

find . -type f -print0|xargs -0 md5sum|sort|perl -ne 'chomp;$ph=$h;($h,$f)=split(/\s+/,$_,2);print "$f"."\x00" if ($h eq $ph)'|xargs -0 rm -v --
2009-06-07 03:14:06
Functions: find perl rm xargs

This one-liner will the *delete* without any further confirmation all 100% duplicates but one based on their md5 hash in the current directory tree (i.e including files in its subdirectories).

Good for cleaning up collections of mp3 files or pictures of your dog|cat|kids|wife being present in gazillion incarnations on hd.

md5sum can be substituted with sha1sum without problems.

The actual filename is not taken into account-just the hash is used.

Whatever sort thinks is the first filename is kept.

It is assumed that the filename does not contain 0x00.

As per the good suggestion in the first comment, this one does a hard link instead:

find . -xdev -type f -print0 | xargs -0 md5sum | sort | perl -ne 'chomp; $ph=$h; ($h,$f)=split(/\s+/,$_,2); if ($h ne $ph) { $k = $f; } else { unlink($f); link($k, $f); }'
find -L /path/to/check -type l -delete
2009-06-06 16:07:04
Functions: find

If you don't want to delete them, but just want to list them, do

find -L /path -type l

If you want to delete them with confirmation first, do

find -L /path -type l -exec rm -i {} +

Using the -L flag follows symlinks, so the -type l test only returns true if the link can't be followed, or is a symlink to another broken symlink.

ls | curl -F 'sprunge=<-' http://sprunge.us | xclip
2009-06-06 11:35:14
User: tatwright
Functions: ls

The URL can then be pasted with a middle click.

This is probably useful when trying to explain problems over instant messaging when you don't have some sort of shared desktop.

ssh -f -N -L 5432:talk.google.com:5222 user@home.network.com
2009-06-05 23:17:21
User: dcabanis
Functions: ssh
Tags: ssh

If your firewall or proxy at your location prevents connection to a particular host or port, you can use ssh to tunnel to your home server and do it there instead.

ssf -f -N -L 4321:home.network.com:25 user@home.network.com
2009-06-05 23:12:02
User: dcabanis
Tags: ssh

Uses ssh as tunnel tunnel for an other connection.

-f runs ssh in the background -N tell that there is no command to run -L deals with the forwarding aspect where the first number is the local port number, the second is parameter is the name of the server to forward to and the third parameter is the port number on that server. The last part of the command is the usual ssh form consisting of the user name and remote server name