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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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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 - 1,330 results
function decToBin { echo "ibase=10; obase=2; $1" | bc; }
2009-11-24 22:57:58
User: woxidu
Functions: echo

Convert some decimal numbers to binary numbers. You could also build a general base-converter:

function convBase { echo "ibase=$1; obase=$2; $3" | bc; }

then you could write

function decToBun { convBase 10 2 $1; }
echo .*
for item in *;do echo -n "$item - ";find "$item" -type f -print0 | xargs -0 file -iNf - | grep video | cut -d: -f1 | xargs -d'\n' /usr/share/doc/mplayer/examples/midentify | grep ID_LENGTH | awk -F= '{sum+=$2} END {print(sum/60)}'; done | grep -v ' - 0$'
2009-11-19 06:28:15
User: jnash
Functions: awk cut echo file grep xargs

I know this has been beaten to death but finding video files using mime types and printing the "hours of video" for each directory is (IMHO) easier to parse than just a single total. Output is in minutes.

Among the other niceties is that it omits printing of non-video files/folders

PS: Barely managed to fit it within the 255 character limit :D

while true; do echo -ne "$(date)\r"; sleep 1; done
2009-11-17 22:45:37
User: polaco
Functions: echo sleep

The above code is just an example of printing on the same line, hit Ctrl + C to stop

When using echo -ne "something\r", echo will:

- print "something"

- dont print a new line (-n)

- interpret \r as carriage return, going back to the start of the line (-e)

Remember to print some white spaces after the output if your command will print lines of different sizes, mainly if one line will be smaller than the previous

Edit from reading comments: You can achieve the same effect using printf (more standardized than echo): while true; do printf "%-80s\r" "$(date)"; sleep 1; done

(echo CD_DA; for f in {01..99}; do echo "$f Hz">&2; sox -nt cdda -r44100 -c2 $f.cdda synth 30 sine $f; echo TRACK AUDIO; echo FILE \"$f.cdda\" 0; done) > cdrdao.toc && cdrdao write cdrdao.toc && rm ??.cdda cdrdao.toc
2009-11-17 06:23:42
User: hackerb9
Functions: cdrdao echo rm write

This command creates and burns a gapless audio CD with 99 tracks. Each track is a 30 second sine wave, the first is 1 Hz, the second 2 Hz, and so on, up to 99 Hz. This is useful for testing audio systems (how low can your bass go?) and for creating the constant vibrations needed to make non-Newtonian fluids (like cornstarch and water) crawl around.

Note, this temporarily creates 500MB of .cdda files in the current directory. If you don't use the "rm" at the end of the command, you can burn more disks using

cdrdao write cdrdao.toc

Prerequisites: a blank CD-R in /dev/cdrw, sox (http://sox.sourceforge.net/), and cdrdao (http://cdrdao.sourceforge.net/). I'm also assuming a recent version of bash for the brace expansion (which just looks nicer than using seq(1), but isn't necessary).

range () { end=$(echo "$1 + $2 - 1" | bc); echo "$1-$end"; }
2009-11-12 22:53:08
User: bartonski
Functions: echo

for example:

echo "..1234567." | cut -c $(range 3 7)



slice="-rw-r--r-- "; ls -l | cut -c $(echo "$slice" | wc -c)-
find <path> -name "*.tgz" -or -name "*.tar.gz" | while read file; do echo "$file: "; tar -tzf $file; done
2009-11-10 20:39:04
User: polaco
Functions: echo find read tar
Tags: find tar list

This script will list all the files in the tarballs present on any folder or subfolder of the provided path. The while loop is for echoing the file name of the tarball before listing the files, so the tarball can be identified

find -name '*.avi' | while read i ; do echo $(mplayer -identify -frames 0 -vo null -nosound "$i" 2>&1 | grep ID_LENGTH | cut -d= -f2)" ""$i" ;done | sort -k1 -r -n | sed 's/^\([^\ ]*\)\ \(.*\)$/\2:\1/g'
2009-11-09 17:14:59
User: ZungBang
Functions: cut echo find grep read sed sort

handles file names with spaces and colons, fixes sort (numeric!), uses mplayer, same output format as other alternatives

for i in *.avi; do echo -n "$i:";mediainfo $i|head | grep PlayTime | cut -d: -f2 ; done | sort -t: -k2 -r
2009-11-09 12:42:20
User: yooreck
Functions: cut echo grep head sort

Similar but using mediainfo instead of totem-something

for i in *.avi; do echo -n "$i:";totem-gstreamer-video-indexer $i | grep DURATION | cut -d "=" -f 2 ; done | sort -t: -k2 -r
2009-11-09 02:59:53
User: iadbungler
Functions: cut echo grep sort

Sort .avi movies by time length, print the longest first, and so on...

(ls; mkdir subdir; echo subdir) | xargs mv
2009-11-08 11:40:55
User: mechmind
Functions: echo mkdir xargs
Tags: xargs pipes

With this form you dont need to cut out target directory using grep/sed/etc.

echo -n "Press any key to continue..." && read
2009-11-06 22:49:46
User: matthewbauer
Functions: echo

This works on some other version of read.

exec 3<>/dev/tcp/whatismyip.com/80; echo -e "GET /automation/n09230945.asp HTTP/1.0\r\nHost: whatismyip.com\r\n" >&3; a=( $(cat <&3) ); echo ${a[${#a[*]}-1]};
echo -e "GET /automation/n09230945.asp HTTP/1.0\r\nHost: whatismyip.com\r\n" | nc whatismyip.com 80 | tail -n1
for c in `seq 0 255`;do t=5;[[ $c -lt 108 ]]&&t=0;for i in `seq $t 5`;do echo -e "\e[0;48;$i;${c}m|| $i:$c `seq -s+0 $(($COLUMNS/2))|tr -d '[0-9]'`\e[0m";done;done
2009-11-03 09:12:13
User: AskApache
Functions: c++ echo

I've been using linux for almost a decade and only recently discovered that most terminals like putty, xterm, xfree86, vt100, etc., support hundreds of shades of colors, backgrounds and text/terminal effects.

This simply prints out a ton of them, the output is pretty amazing.

If you use non-x terminals all the time like I do, it can really be helpful to know how to tweak colors and terminal capabilities. Like:

echo $'\33[H\33[2J'
for x in `find /vmfs/volumes/ -name *vmx -exec grep -H linux.iso {} \; |cut -d : -f 1`; do echo $x; grep -i sync $x; done;
2009-10-30 16:19:16
User: uid0
Functions: cut echo grep sync

besure to adjust your find to use to correct location of your VMX files.

newest () { candidate=''; for i in "$@"; do [[ -f $i ]] || continue; [[ -z $candidate || $i -nt $candidate ]] && candidate="$i"; done; echo "$candidate"; }
2009-10-29 17:35:01
User: johnraff
Functions: echo
Tags: bash files

Usage example:

newest Desktop/*

Replace "-nt" with "-ot" for oldest.


shopt -s dotglob

first to include dotfiles.

echo {001..5}
2009-10-29 16:25:44
User: nanard06
Functions: echo
Tags: bash

bash2 : for X in $(seq 1 5); do printf "%03g " "$X";done

bash3 : for X in {1..5}; do printf "%03g " "$X";done

bash4 : echo {001..5}

alias clear='( for ((i=1;i<$LINES;i++)) ; do echo "" ; done ) ; clear'
2009-10-27 14:38:31
User: Marcio
Functions: alias echo

If you receives a lot of compiling errors, type 'clear', then reedit your code and press "SHIFT+PGUP".

export PROMPT_COMMAND='( x=$? ; let x!=0 && echo shell returned $x )'
genpass() { local h x y;h=${1:-8};x=( {a..z} {A..Z} {0..9} );y=$(echo ${x[@]} | tr ' ' '\n' | shuf -n$h | xargs);echo -e "${y// /}"; }
2009-10-24 04:05:42
User: twfcc
Functions: echo tr

make password randomly, default 8 char

curl -fs brandx.jp.sme 2&>1 > /dev/null || echo brandx.jp.sme ping failed | mail -ne -s'Server unavailable' [email protected]
2009-10-23 14:29:06
User: mccalni
Functions: echo mail ping
Tags: bash ping curl mail

Alternative to the ping check if your firewall blocks ping. Uses curl to get the landing page silently, or fail with an error code. You can probably do this with wget as well.

wmctrl -o 2560,0 ;sleep 2 ; echo "FIRE 001" | osd_cat -o 470 -s 8 -c red -d 10 -f -*-bitstream\ vera\ sans-*-*-*--250-*-*-*-*-*-*-* ; sleep 1; wmctrl -o 0,0
2009-10-23 10:00:51
User: m33600
Functions: echo sleep

Strip my code to:

wmctrl -o 0,0 # autorotates to the first face. In fact [0-1279],0

wmctrl - 1280,0 # goes to the second face

wmctrl -o 2560,0 # goes to the third face, and so on.

# Use multiples of the horizontal display resolution.

My example work for 1280x800 display, been 1280 the number of interest.

Tweak the number, try a biiiig one and see your cube spinning...

I put a complex example to show how fun things can be, even for my ademco and paradox alarm central network advisor interface xpto etc. It rotates two faces, print the alarm message, and goes back tho where it was.

Tested on BIGLINUX 4.2, equivalent to ubuntu LTS hardy.

Do not forget to activate 3D efects ( compiz cube )

export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | toilet -f shadow'
2009-10-23 07:56:30
User: m33600
Functions: date echo export printf watch

already described on the other two versions, this one uses ascii characters on game style to display elapsed time.