Hide

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.


If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Hide

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

Hide

News

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.
Hide

Tags

Hide

Functions

Commands using echo from sorted by
Terminal - Commands using echo - 1,227 results
range () { end=$(echo "$1 + $2 - 1" | bc); echo "$1-$end"; }
2009-11-12 22:53:08
User: bartonski
Functions: echo
0

for example:

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

yields

1234567

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
-2

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
2

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
0

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
1

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
4

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
-4

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
15

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
0

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
1

Usage example:

newest Desktop/*

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

Run

shopt -s dotglob

first to include dotfiles.

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

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
-3

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
-1

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
2

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
5

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
0

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
0

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
3

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
0

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 }