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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




Commands using echo from sorted by
Terminal - Commands using echo - 1,221 results
(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' joker@jp.co.uk
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.

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) | osd_cat -o 20 -d 1 -p bottom'
2009-10-23 07:47:11
User: m33600
Functions: date echo export printf watch

Variation of the theme, this one blinks in low profile on top level of X, ie, it is visible, indeed small.

Try changing fonts and sizes of osd_cat

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)'
2009-10-23 07:31:44
User: m33600
Functions: date echo export printf watch

Works on real time clock, unix time based, decrementing the actual time from initial time saved in an environment variable exported to child process inside watch

Shows elapsed time from start of script in hh:mm:ss format

Non afected by system slow down due to the use of date.

pushd .> /dev/null; cd /; for d in `echo $OLDPWD | sed -e 's/\// /g'`; do cd $d; echo -n "$d "; ls -ld .; done; popd >/dev/null
2009-10-22 12:32:11
User: syladmin
Functions: cd echo ls sed
Tags: permissions

Can easily be scripted in order to show permission "tree" from any folder. Can also be formated with

column -t

{ pushd .> /dev/null; cd /; for d in `echo $OLDPWD | sed -e 's/\// /g'`; do cd $d; echo -n "$d "; ls -ld .; done; popd >/dev/null ; } | column -t

from http://www.commandlinefu.com/commands/view/3731/using-column-to-format-a-directory-listing

echo $(shuf -i 1-49 | head -n6 | sort -n)
seg() { for b in $(echo $1); do for x in $(seq 10); do echo $b.$x; done; done }
seg() { echo -e "$1" | while read LINE; do for b in $(seq 10); do echo $LINE.$b; done; done; }
echo -e "n\np\n1\n\n\nt\n8e\nw" | fdisk /dev/sdX
2009-10-20 16:21:54
User: sud0er
Functions: echo fdisk
Tags: Linux fdisk

This is a bit hacky, but if you're setting up a bunch of new LUNs, it can save a bunch of time. Also check out sfdisk. The fdisk will fail if, for example, a partition table already exists.

for a in bzip2 lzma gzip;do echo -n>$a;for b in $(seq 0 256);do dd if=/dev/zero of=$b.zero bs=$b count=1;c=$(date +%s%N);$a $b.zero;d=$(date +%s%N);total=$(echo $d-$c|bc);echo $total>>$a;rm $b.zero *.bz2 *.lzma *.gz;done;done
2009-10-20 01:00:51
User: matthewbauer
Functions: bzip2 date dd echo seq

See: http://imgur.com/JgjK2.png for example.

Do some serious benchmarking from the commandline. This will write to a file with the time it took to compress n bytes to the file (increasing by 1).


gnuplot -persist <(echo "plot 'lzma' with lines, 'gzip' with lines, 'bzip2' with lines")

To see it in graph form.

echo start > battery.txt; watch -n 60 'date >> battery.txt ; acpi -b >> battery.txt'
2009-10-19 05:28:15
User: m33600
Functions: acpi echo watch

This time I added a print to reemaining energy, every minute, time stamped.

The example shown here is complete and point to large discrepancies as time passes, converging to accuracy near the end.

echo start > battery.txt; watch -n 60 'date >> battery.txt'
2009-10-18 07:00:26
User: m33600
Functions: echo watch

Fully recharge your computer battery and start this script.

It will create or clean the file named battery.txt, print a start on it and every minute it will append a time stamp to it.

Batteries last few hours, and each hour will have 60 lines of time stamping. Really good for assuring the system was tested in real life with no surprises.

The last time stamp inside the battery.txt file is of interest. It is the time the computer went off, as the battery was dead!

Turn on your computer after that, on AC power of course, and open battery.txt. Read the first and last time stamps and now you really know if you can trust your computer sensors.

If you want a simple line of text inside the battery.txt file, use this:

watch -n 60 'date > battery.txt'

The time of death will be printed inside

echo -n a | od -d | sed -n "s/^.* //gp"
2009-10-17 15:46:00
User: stf42
Functions: echo od sed

the shortest command for character 'a' i know