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Commands using echo

Commands using echo from sorted by
Terminal - Commands using echo - 1,102 results
alarmclock() { [ $1 ] || echo Parameter TIME is missing. 1>&2 && return 1 ; ( sleep $1 ; for x in 9 8 7 6 5 4 3 2 1 ; do for y in `seq 0 $[ 10 - $x ] ` ; do printf "\a"; sleep 0.$x ; done ; done ) & }
2012-08-16 15:35:15
User: lkj
Functions: echo printf return sleep
0

usage: alarmclock TIME

TIME is a sleep(1) parameter which tells function how long to wait until raise the alarm.

echo 00:29:36 | sed s/:/*60+/g | bc
vlc $(for f in /proc/$(pgrep -f libflashplayer.so |head -n 1)/fd/*; do ;if $(file ${f} |grep -q "broken symbolic link to \`/tmp/FlashXX"); then echo ${f};fi;done)
echo 3 > /proc/sys/vm/drop_caches
for i in $(tmux list-windows -F '#{window_index}'); do panenames=$(tmux list-panes -t $i -F '#{pane_title}' | sed -e 's/:.*$//' -e 's/^.*@//' | uniq); windowname=$(echo ${panenames} | sed -e 's/ /|/g'); tmux rename-window -t $i $windowname; done
2012-08-03 01:43:51
User: mrfixit42
Functions: echo sed
Tags: tmux byobu
0

*I run this with byobu as as a custom status bar entry that runs every 10 seconds by putting it in a script here:

.byobu/bin/10_update_windows

There's no output to stdout, so nothing is displayed on the status bar.

*Presumes that #{pane_title} is set to the hostname or prompt containing the host name. In my case, it's in this format:

$USER@$HOSTNAME:$PWD

The sed commands may need to be modified if your pane_title is different.

*If you want to strip out a common part of a hostname, add the following before '| uniq'

-e 's/[COMMON PART]//'

I use that to strip out the domain of the servers I connect to, leaving the subdomain.

egrep_escape() { echo "$1" |sed -re 's/([\\.*+?(|)^$[])/\\\1/g' -e 's/\{/[{]/g'; }
2012-08-02 16:54:43
User: regnarg
Functions: echo sed
Tags: grep escape
0

Use if you want to include untrusted literal strings in your grep regexes.

I use it to list all mounts below a directory:

dir=/mnt/gentoo; cat /proc/mounts |awk '{print $2}' |egrep "^$(egrep_escape "$dir")(/|$)"

/mnt/gentoo

/mnt/gentoo/proc

/mnt/gentoo/sys

/mnt/gentoo/dev

/mnt/gentoo/home

Works even if $dir contains dangerous characters (e.g. comes from a commandline argument).

export PATH= $(echo $PATH | tr ':' '\n' | awk '!/matching string/' | paste -sd:)
echo "DESCRIBE dbname.table_name" | mysql -u dbusername | awk '{print $1}' | grep -v Field
2012-07-26 21:06:11
User: adauto
Functions: awk echo grep
0

You can execute this inside an editor to get all the fields inside your buffer and do the magic, really usefull when your tables contain a giant list of fields.

prefix="169.254" && for i in {0..254}; do echo $prefix.$i/8; for j in {1..254}; do sh -c "ping -m 1 -c 1 -t 1 $prefix.$i.$j | grep \"icmp\" &" ; done; done
2012-07-25 12:07:15
User: tempelorg
Functions: echo sh
Tags: ping
0

This version combines the best of the other suggestions and adds these features:

1. It scans a /16 subnet

2. It is very fast by running the ping commands in the background, running them in parallel.

3. Does not use the "-W" option as that's not available in older ping versions (I needed this for OS X 10.5)

echo "properly_escaped_command" | ssh user@host $(< /dev/fd/0)
2012-07-18 10:36:07
User: trantorvega
Functions: echo ssh
2

It executes commands as arguments to ssh, avoiding problematic shell expansions, without the need of writing the commands in question to a temporary file, just reading them from STDIN.

goWall() { if [ $# -ne 1 ]; then echo 'goWall image';return;fi;w=w.jpg;o="$1";f="$1"-f;of="$1"-af;off="$1"-aff;convert "$1" -flop $f;montage -geometry +0+0 -tile 2x "$1" $f $of;convert $of -flip $off;montage -geometry +0+0 -tile 1x $of $off $w }
2012-07-17 05:01:58
User: meathive
Functions: echo
0

This command clones an image three times and creates a 'tile' image that can be used for a repeating pattern wallpaper. Add 'rm $f $of $off' to the end for cleanup (command was too long to submit with it).

See this link for an example: http://meathive.deviantart.com/art/Easy-Photography-Hack-314846774

for i in /var/spool/cron/tabs/*; do echo ${i##*/}; sed 's/^/\t/' $i; echo; done
2012-07-12 08:07:20
User: harpo
Functions: echo sed
1

This is flatcaps tweaked command to make it work on SLES 11.2

for i in /var/spool/cron/*; do echo ${i##*/}; sed 's/^/\t/' $i; echo; done
for user in $(getent passwd|cut -f1 -d:); do echo "### Crontabs for $user ####"; crontab -u $user -l; done
2012-07-11 13:06:17
User: harpo
Functions: crontab cut echo getent
Tags: crontab getent
0

added echo "### Crontabs for $user ####"; to make clear whose crontab is listed.

for user in $(cut -f1 -d: /etc/passwd); do echo "### Crontabs for $user ####"; crontab -u $user -l; done
2012-07-11 12:25:56
User: harpo
Functions: crontab cut echo
Tags: crontab
3

added echo "### Crontabs for $user ####"; to make clear whose crontab is listed.

SEED=$(head -1 /dev/urandom|od -N 1);for i in {1..10};do tmp=$(mkpasswd ${RANDOM});pass=${tmp:2:6};echo Pass $pass Crypt: $(mkpasswd $pass);done
echo http://www.TheWebSiteName.com privatekeyword | md5sum | awk '{print substr($0,0,10)}'
2012-06-28 11:32:08
User: ertjies
Functions: awk echo md5sum
0

Create a bash function for easy reference

webPassword()

{

echo $1 $2 | md5sum | awk '{print substr($0,0,10)}'

}

alias webpwd=webPassword

Use like this.

webpwd www.commandlinefu.com MyPetNameHere

hourglass(){ trap 'tput cnorm' 0 1 2 15 RETURN;local s=$(($SECONDS +$1));(tput civis;while (($SECONDS<$s));do for f in '|' '\' '-' '/';do echo -n "$f";sleep .2s;echo -n $'\b';done;done;);}
2012-06-21 05:40:22
User: AskApache
Functions: echo sleep tput trap
13

Displays an animated hourglass for x amount of seconds

svn status | grep "^M" | while read entry; do file=`echo $entry | awk '{print $2}'`; echo $file; svn revert $file; done
2012-06-17 16:01:06
User: wsams
Functions: awk echo grep read
0

This command allows you to revert every modified file one-by-one in a while loop, but also after "echo $file;" you can do any sort of processing you might want to add before the revert happens.

[ $V ] || : $((V++)) && echo $V
2012-06-15 16:48:03
User: axelabs
Functions: echo
2

I just found another use for the builtin ':' bash command. It increments counters for me in a loop if a certain condition is met...

: [arguments]

No effect; the command does nothing beyond expanding arguments and performing any specified redirections. A zero exit code is returned.

grep -r -Z -l "<text>" . | xargs -0 echo rm
2012-06-14 08:09:46
User: limonte
Functions: echo grep xargs
Tags: grep
4

-r recursively

-Z zero byte after each file name instead of the usual newline

-l only filenames

read -s p && echo -n $p | md5sum;p=
2012-06-08 13:50:50
User: hoodie
Functions: echo read
1

create and md5 sum of your password without it showing up in your terminal or history.

Afterwards we overwrite the $p variable (thx to bazzargh)

#!/bin/zsh SHL='\\e[0;31m' EHL='\\e[0m' while read line; do TEXT=$line for SSTR in $*; do TEXT=$(echo $TEXT | sed -e "s:$SSTR:${SHL}${SSTR}${EHL}:g") done echo -e $TEXT done
echo -n 'the_password' | md5sum -
set str=user_pref("browser.startup.homepage", "http://www.fcisolutions.com/"); cd = "%APPDATA%\Mozilla\Firefox\Profiles\*.default\" echo %str%>>prefs.js
2012-05-30 18:50:15
User: Micool777
Functions: cd echo set
1

Pros: Works in all Windows computers, most updated and compatible command.

Cons: 3 liner

Replace fcisolutions.com with your site name.