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Commands using echo from sorted by
Terminal - Commands using echo - 1,221 results
for i in `du --max-depth=1 $HOME | sort -n -r | awk '{print $1 ":" $2}'`; do size=`echo $i | awk -F: '{print $1}'`; dir=`echo $i | awk -F: '{print $NF}'`; size2=$(($size/1024)); echo "$size2 MB used by $dir"; done | head -n 10
echo string | tr '[:lower:]' '[:upper:]'
sort -n <( for i in $(find . -maxdepth 1 -mindepth 1 -type d); do echo $(find $i | wc -l) ": $i"; done;)
(($RANDOM%6)) || echo 'hello world!'
2009-05-27 08:11:08
User: luishka
Functions: echo
-8

ramdomize the execution of the command echo 'hello world!'

season=1; for file in $(ls) ; do dir=$(echo $file | sed 's/.*S0$season\(E[0-9]\{2\}\).*/\1/'); mkdir $dir ; mv $file $dir; done
2009-05-27 03:30:58
User: lonecat
Functions: echo file mkdir mv sed
-1

It happened to me that I got a season of a tv-show which had all files under the same folder like /home/blah/tv_show/season1/file{1,2,3,4,5,...}.avi

But I like to have them like this:

/home/blah/tv_show/season1/e{1,2,3,4,5,...}/file{1,2,3,4,5,...}.avi

So I can have both the srt and the avi on one folder without cluttering much. This command organizes everything assuming that the filename contains Exx where xx is the number of the episode.

You may need to set:

IFS=$'\n'

if your filenames have spaces.

kill_daemon() { echo "Daemon?"; read dm; kill -15 $(netstat -atulpe | grep $dm | cut -d '/' -f1 | awk '{print $9}') }; alias kd='kill_daemon
2009-05-26 20:39:56
User: P17
-5

Just find out the daemon with $ netstat -atulpe. Then type in his name and he gets the SIGTERM.

sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e
2009-05-25 05:37:44
User: mohan43u
Functions: echo sed xargs
10
echo "http%3A%2F%2Fwww.google.com" | sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e

http://www.google.com

Works under bash on linux. just alter the '-e' option to its corresponding equivalence in your system to execute escape characters correctly.

F="$HOME/.moz*/fire*/*/session*.js" ; grep -Go 'entries:\[[^]]*' $F | cut -d[ -f2 | while read A ; do echo $A | sed s/url:/\n/g | tail -1 | cut -d\" -f2; done
2009-05-21 21:58:42
User: b2e
Functions: cut echo grep read sed tail
3

Tuned for short command line - you can set the path to sessionstore.js more reliable instead of use asterixes etc.

Usable when you are not at home and really need to get your actual opened tabs on your home computer (via SSH). I am using it from my work if I forgot to bookmark some new interesting webpage, which I have visited at home. Also other way to list tabs when your firefox has crashed (restoring of tabs doesn't work always).

This script includes also tabs which has been closed short time before.

echo $BASH_VERSION
find . -name "*.jar" | while read file; do echo "Processing ${file}"; jar -tvf $file | grep "Foo.class"; done
date -d2009-05-18 > /dev/null 2>&1 ; echo $?
2009-05-18 20:30:05
User: GeckoDH
Functions: date echo
2

Important to know: a valid date will return 0, otherwise 1!

echo 2006-10-10 | grep -c '^[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]$'
2009-05-11 22:18:43
User: rez0r
Functions: echo grep
-1

Quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean, the regex can easily be upgraded to handle "in betweens" for mm dd or to validate other types of strings, ex. ip address.

Boolean output could easily be piped into a condition for a more complete one-liner.

function echox { echo `tput cup $(($(tput lines))) $(( ($(tput cols) - $(echo "${#1}"))/2 ))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; }
2009-05-10 23:24:49
Functions: echo tput
1
function echox { echo `tput cup $(($(tput lines))) $(( ($(tput cols) - $(echo "${#1}"))/2 ))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; }

echox prints given argument on bottom line center screen in terminal

function echoxy { echo `tput cup $(($(tput lines)/2)) $(( ($(tput cols) - $(echo "${#1}"))/2))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; }

exhoxy prints given argument center screen

function echos { echo `tput cup $(($(tput lines)-2)) $(($(tput cols)-$(echo ${#1})))&&tput sc`"$1"`tput cup $(($(tput lines)-2)) 0 && tput rc`; } while [ 1 ]; do echos "`date`"; done

echos prints date and time on second from last line (used as status message)

you can easily use these functions by placing them in your .bashrc file, make sure to source your .bashrc once you do

echo '{"json":"obj"}' | python -m simplejson.tool
2009-05-10 13:58:05
User: azeey
Functions: echo python
Tags: python json
11

You can use a site like http://www.jsonlint.com/ or use the command line to validate your long and complex json data. This is part of the simplejson package for python http://undefined.org/python/#simplejson.

Wrong json expression example:

echo '{ 1.2:3.4}' | python -m simplejson.tool

Expecting property name: line 1 column 2 (char 2)

for i in `seq -w 1600` ; do links -dump http://www.robsjokes.com/$i/index.html | sed '/Random Joke/,/Next Joke/!d' | sed '/^$/,/^$/!d' >> ~/temp/Rob.jokes ; echo '%' >> ~/temp/Rob.jokes ; done
echo $?
2009-05-09 17:32:23
Functions: echo
11

The variable ? contain the last exit status of a command, it can be printed for troubleshooting purpose.

echo 00{1..9} 0{10..99} 100
screen -dmS "name_me" echo "hi"
2009-05-06 02:04:15
Functions: echo screen
3

Runs an instance of screen with name of "name_me" and command of "echo "hi""

To reconnect to screen instance later use:

screen -r name_me

gnuplot -persist <(echo "plot '<(sort -n listOfNumbers.txt)' with lines")
2009-05-02 13:46:02
User: penthief
Functions: echo
21

Useful when you've produced a large file of numbers, and want to quickly see the distribution. The value of y halfway along the x axis is the median. Simple!

Just create the listOfNumbers.txt file with a number on each line to try it out.

perm=( 6 4 4 ) ; for elem in ${perm[@]}; do echo `expr 7 - $elem` ; done
2009-05-01 12:08:19
Functions: echo
1

Umask is obtained subtracting 7 from each cypher of octal format. I store octal perm format in an array,then for each element of array I subtract 7. The result is the umask.

_llines=100; while [ $_llines -gt 1 ]; do echo $_llines; _llines=$(($_llines-1)); done
2009-04-29 00:19:45
User: romulusnr
Functions: echo
-2

You've opened a terminal window and you've connected off to a remote host that didn't pick up your terminal size, and all your curses and paging apps are screwed up as a result. You need to quickly determine how many lines are in your current terminal view (to feed into "stty rows X").

echo "screen -DR" >> ~/.bash_profile
2009-04-28 20:45:37
User: sud0er
Functions: echo
Tags: screen
11

From screen's manpage: "Attach here and now. In detail this means: If a session is running, then reattach. If necessary detach and logout remotely first. If it was not running create it and notify the user. This is the author's favorite."

Toss this in your ~/.bash_profile so that you never have that "oh crap" moment where you wanted to run something in screen and didn't.

echo "Hello world" | base64
2009-04-27 15:00:08
User: P17
Functions: echo
Tags: encoding
-3

Also works with files:

cat file

Hello world

base64 file

SGVsbG8gd29ybGQK

To decrypt use the -d option:

echo SGVsbG8gd29ybGQK | base64 -d

Hello world

for i in /sys/class/net/*; do e=`basename $i`; echo "# $e"; sudo ethtool $e | grep -E "Link|Speed" ; done
2009-04-25 14:32:08
User: hank
Functions: echo grep sudo
Tags: Network Linux
0

Basically an improvement on an earlier ethtool command line.

echo "A great password" | md5sum
2009-04-24 14:32:56
User: ubersoldat
Functions: echo
-5

You can also use sha1sum and variants for longer passwords