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awk, bash, curl, find, grep, Linux, sed
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Functions

Commands using echo from sorted by
Terminal - Commands using echo - 1,336 results
dpkg --get-selections | cut -f1 | while read pkg; do dpkg -L $pkg | xargs -I'{}' bash -c 'if [ ! -d "{}" ]; then echo "{}"; fi' | tr '\n' '\000' | du -c --files0-from - | tail -1 | sed "s/total/$pkg/"; done
2009-10-12 14:57:54
User: pykler
Functions: bash cut du echo read sed tail tr xargs
Tags: Debian wajig
4
Up
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List your largest installed packages.

Calculates the size on disk for each package installed on the filesystem (or removed but not purged). This is missing the

| sort -rn

which would put the biggest packges on top. That was purposely left out as the command is slightly on the slow side

Also you may need to run this as root as some files can only be checked by du if you can read them ;)

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
b="http://2010.utosc.com"; for p in $( curl -s $b/presentation/schedule/ | grep /presentation/[0-9]*/ | cut -d"\"" -f2 ); do f=$(curl -s $b$p | grep "/static/slides/" | cut -d"\"" -f4); if [ -n "$f" ]; then echo $b$f; curl -O $b$f; fi done
2009-10-11 17:28:46
User: danlangford
Functions: cut echo grep
Tags: curl cut for UTOSC
2
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download all the presentations from UTOSC2010

miss a class at UTOSC2010? need a refresher? use this to curl down all the presentations from the UTOSC website. (http://2010.utosc.com) NOTE/WARNING this will dump them in the current directory and there are around 37 and some are big - tested on OSX10.6.1

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ifs () { echo -n "${IFS}"|hexdump -e '"" 10/1 "'\''%_c'\''\t" "\n"' -e '"" 10/1 "0x%02x\t" "\n\n"'|sed "s/''\|\t0x[^0-9]//g; $,/^$/d"
2009-10-10 22:41:35
User: dennisw
Functions: echo hexdump sed
Tags: IFS fields separator
2
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Functions to display, save and restore $IFS

You can display, save and restore the value of $IFS using conventional Bash commands, but these functions, which you can add to your ~/.bashrc file make it really easy.

To display $IFS use the function ifs shown above. In the sample output, you can see that it displays the characters and their hexadecimal equivalent.

This function saves it in a variable called $saveIFS:

sifs () { saveIFS=$IFS; }

Use this function to restore it

rifs () { IFS=$saveIFS; }

Add this line in your ~/.bashrc file to save a readonly copy of $IFS:

declare -r roIFS=$IFS

Use this function to restore that one to $IFS

rrifs () { IFS=$roIFS; }
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head -c10 <(echo $RANDOM$RANDOM$RANDOM)
2009-10-09 15:09:02
User: jgc
Functions: echo head
Tags: HEAD random
0
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Outputs a 10-digit random number

Makes use of $RANDOM environment variable.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
if [ "$testnum" -eq "$testnum" 2>/dev/null ]; then echo It is numeric; fi
2009-10-09 14:57:27
User: jgc
Functions: echo
Tags: validation numbers
0
Up
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Check if variable is a number

Using the standard numeric comparison but suppressing the STDERR output acts as the simplest way to check a value is numeric. See sample output for some examples.

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echo $X | egrep "^[0-9]+$"
2009-10-09 13:59:47
User: sharfah
Functions: echo egrep
-1
Up
Down
Check if variable is a number
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for USER in `ls /var/spool/cron`; do echo "=== crontab for $USER ==="; echo $USER; done
2009-10-08 23:51:43
User: jemmille
Functions: echo
-4
Up
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print crontab entries for all the users that actually have a crontab

Lists crontab for all users on system that have crontabs.

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tput smcup; echo "Doing some things..."; sleep 2; tput rmcup
2009-10-08 16:48:04
User: jgc
Functions: echo sleep tput
8
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Using tput to save, clear and restore the terminal contents

Very useful for interactive scripts where you would like to return the terminal contents to its original state before the script was run. This would be similar to how vi exits and returns you to your original terminal screen.

Save and clear the terminal contents with:

tput smcup

Execute some commands, then restore the saved terminal contents with:

tput rmcup
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for USER in `cut -d ":" -f1 </etc/passwd`; do crontab -u ${USER} -l 1>/dev/null 2>&1; if [ ! ${?} -ne 0 ]; then echo -en "--- crontab for ${USER} ---\n$(crontab -u ${USER} -l)\n"; fi; done
2009-10-07 20:51:01
User: tharant
Functions: crontab echo
4
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print crontab entries for all the users that actually have a crontab

This is how I list the crontab for all the users on a given system that actually have a crontab.

You could wrap it with a function block and place it in your .profile or .bashrc for quick access.

There's prolly a simpler way to do this. Discuss.

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echo "vertical text" | fold -1
2009-10-05 23:20:14
User: zude
Functions: echo fold
Tags: column headers redirection paste process substitution
3
Up
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Print text string vertically, one character per line.
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sitepass() { echo -n "[email protected]" | md5sum | sha1sum | sha224sum | sha256sum | sha384sum | sha512sum | gzip - | strings -n 1 | tr -d "[:space:]" | tr -s '[:print:]' | tr '!-~' 'P-~!-O' | rev | cut -b 2-11; history -d $(($HISTCMD-1)); }
2009-10-01 20:14:57
User: syssyphus
Functions: cut echo gzip md5sum rev sha1sum strings tr
Tags: Security
14
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generate a unique and secure password for every website that you login to

usage: sitepass MaStErPaSsWoRd example.com

description: An admittedly excessive amount of hashing, but this will give you a pretty secure password, It also eliminates repeated characters and deletes itself from your command history.

tr '!-~' 'P-~!-O' # this bit is rot47, kinda like rot13 but more nerdy

rev # this avoids the first few bytes of gzip payload, and the magic bytes.

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echo $(</tmp/foo)
2009-10-01 12:43:20
User: tatsu
Functions: echo
6
Up
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Change newline to space in a file just using echo

Changing newline to spaces using just echo

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expdp user/password FLASHBACK_SCN=$(echo -e "select current_scn from v\$database;" | sqlplus / as sysdba 2>/dev/null| grep [0-9][0-9][0-9][0-9][0-9][0-9]*)
2009-10-01 08:55:20
User: peshay
Functions: as echo grep
0
Up
Down
Consistent Oracle Datapump Export

Creates a consistent datapumpt export on an Oracle database with the current sequence number, while the system is running and changes happens on the database.

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check_dns_no() { for i in $* ; do if `wget -O - -q http://www.norid.no/domenenavnbaser/whois/?query=$i.no | grep "no match" &>/dev/null` ; then echo $i.no "available" ; fi ; sleep 1 ;done }
2009-09-30 21:17:33
User: xeor
Functions: echo grep sleep
Tags: wget dig dns
0
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Check if a .no domain is available

Mostly for Norwegians, but easily adoptable to others. Very handy if you are brainstorming for a new domainname.

Will only display the available ones..

You can usually do this better with dig, but if you dont have dig, or the TLD only have an online service to check with, this will be usefull..

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(crontab -l; echo '* * * * * dmesg -c'; ) | crontab -
2009-09-30 18:13:38
User: syssyphus
Functions: crontab dmesg echo
6
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send kernel log (dmesg) notifications to root via cron

this is helpful because dmesg is where i/o errors, etc are logged to... you will also be able to see when the system reboots or someone attaches a thumb drive, etc.

don't forget to set yourself up in /etc/aliases to get roots email.

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echo "Starting Daemon"; ( while :; do sleep 15; echo "I am still running =]"; done ) & disown -h -ar $!
2009-09-30 16:00:13
User: tatsu
Functions: echo sleep
8
Up
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A little bash daemon =)

A little bash daemon

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s=124890; array=($(echo $s | sed 's/./& /g')); echo ${array[@]}; echo ${!array[@]}
2009-09-29 12:30:04
User: tatsu
Functions: echo sed
0
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convert string to array

Convert string to array using echo and sed =)

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[ `date --date='next day' +'%B'` == `date +'%B'` ] || echo 'end of month'
2009-09-29 11:46:35
User: pc1500
Functions: echo
9
Up
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is today the end of the month?
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PERMA () { echo "[email protected]" >> ~/.bashrc; }
2009-09-28 16:03:24
User: zlemini
Functions: echo
2
Up
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Make alias pemanent fast

Simple function to permanently add an alias to your profile.

Tested on bash and Ksh, bash version above.

Here is the ksh version: PERMA () { print "[email protected]" >> ~/.profile; }

Sample usage:

PERMA alias la='ls -a'

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echo -e "\e[32m"; while :; do for i in {1..16}; do r="$(($RANDOM % 2))"; if [[ $(($RANDOM % 5)) == 1 ]]; then if [[ $(($RANDOM % 4)) == 1 ]]; then v+="\e[1m $r "; else v+="\e[2m $r "; fi; else v+=" "; fi; done; echo -e "$v"; v=""; done
2009-09-27 15:30:38
User: dennisw
Functions: echo
Tags: color
21
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Matrix Style

I like the fact the Patola's version uses only ones and zeros, but I also like the sparse output of the other versions. This one combines both of those features and eliminates some unnecessary cruft.

You can vary the sparseness by changing "$(($RANDOM % 5))" to another number. The number in this term "$(($RANDOM % 4))" controls how frequently the numbers are output bold.

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echo "blacklist pcspkr"|sudo tee -a /etc/modprobe.d/blacklist.conf
2009-09-27 11:42:47
User: sliceoflinux
Functions: echo sudo tee
Tags: Ubuntu speaker beep
5
Up
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Disable beep sound from your computer

This command will disable the beep sound from the PC speaker.

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beepwhenup () { echo 'Enter host you want to ping:'; read PHOST; if [[ "$PHOST" == "" ]]; then exit; fi; while true; do ping -c1 -W2 $PHOST 2>&1 >/dev/null; if [[ "$?" == "0" ]]; then for j in $(seq 1 4); do beep; done; ping -c1 $PHOST; break; fi; done; }
2009-09-24 18:11:10
User: linuxrawkstar
Functions: echo host ping read seq
Tags: ping beep
2
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ping a host until it responds, then play a sound, then exit

After this, just type:

beepwhenup

You need to install "beep" before this would make the beep sound.

Save it in your .profile if you want to use it later

WARNING: this command won't exit until it is successful. You won't be able to CONTROL+C out of it.

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echo $PATH|tr : '\n'|sort|uniq -d
2009-09-24 17:22:45
User: haivu
Functions: echo tr uniq
0
Up
Down
Find duplicate dir in path
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host A: cat /proc/dev/ttyS0 host B: echo hello > /dev/ttyS0
2009-09-24 13:22:23
User: flart
Functions: cat echo host
2
Up
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Test a serial connection

If the connection works you should see a "hello" on host A. If not: check your cabeling etc :-)

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mplayer -vo dummy -ao dummy -identify * 2>&1 | grep ID_LENGTH | sed 's/.*=\([0-9]*\)/\1/' | xargs echo | sed 's/ /+/g' | bc | awk 'S=$1; {printf "%dh:%dm:%ds\n",S/(60*60),S%(60*60)/60,S%60}'
2009-09-24 10:33:19
User: Strawp
Functions: awk bc echo grep sed xargs
5
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Get the total length of all videos in the current dir in H:m:s

You're behind on your TV catch-up, but how far behind? This command tries to open mplayer against all files in the current dir. If it's a video file it will contain ID_LENGTH, which is summed and output in hours, minutes and seconds.

Someone better at awk could probably reduce this down a lot.

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