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Commands using echo

Commands using echo from sorted by
Terminal - Commands using echo - 1,102 results
echo "abcdefg"|awk 'BEGIN {FS="''"} {print $2}'
2012-10-25 16:12:28
User: omatictost
Functions: awk echo
0
Up
Down
Print a single character from a string with AWK.
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echo 1268727836 | awk '{print strftime("%c",$1)}'
2012-10-25 15:39:08
User: omatictost
Functions: awk echo
0
Up
Down
Display EPOCH time in human readable format using AWK.
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for i in `ls /sys/class/net/`; do echo $i: `cat /sys/class/net/$i/operstate`; done
2012-10-15 18:20:37
User: dragonauta
Functions: echo
Tags: Network device
0
Up
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Check the status of a network interface

no need for installing mii-tools, all generic tools

working under archlinux.

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for P in $(mount | awk '/type nfs / {print $3;}'); do echo $P; sudo umount $P && sudo mount $P && echo "ok :)"; done
2012-10-14 22:39:58
User: amatix
Functions: awk echo mount sudo umount
Tags: Linux mount nfs
0
Up
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Remount all NFS mounts on a host

`mount -o remount` doesn't pick up new NFS options (eg. timeo, soft, retrans, etc) so you need to do a full mount/remount cycle. This one-liner makes it quick and easy :) Update your fstab with the new options, then run it.

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echo 'scale=10; 4*a(1)' | bc -l
2012-10-08 15:03:07
User: chars19
Functions: bc echo
Tags: bc -l
1
Up
Down
Calculate pi with specific scale

a() function in bc is for arctangent, available if using -l option included.

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "$: << '.'" >> $IRBRC
2012-10-05 16:26:27
User: emmasteimann
Functions: echo
Tags: PATH rails ruby
0
Up
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Add current directory to Ruby load path
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NUMCPUS=`grep ^proc /proc/cpuinfo | wc -l`; FIRST=`cat /proc/stat | awk '/^cpu / {print $5}'`; sleep 1; SECOND=`cat /proc/stat | awk '/^cpu / {print $5}'`; USED=`echo 2 k 100 $SECOND $FIRST - $NUMCPUS / - p | dc`; echo ${USED}% CPU Usage
2012-10-02 03:57:51
User: toxick
Functions: awk echo sleep wc
Tags: cpu shell usage ps command percentage
0
Up
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Display CPU usage in percentage

Using the output of 'ps' to determine CPU usage is misleading, as the CPU column in 'ps' shows CPU usage per process over the entire lifetime of the process. In order to get *current* CPU usage (without scraping a top screen) you need to pull some numbers from /proc/stat. Here, we take two readings, once second apart, determine how much IDLE time was spent across all CPUs, divide by the number of CPUs, and then subtract from 100 to get non-idle time.

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while [ 1 ] ; do echo -en "$(date +%T)\r" ; sleep 1; done
2012-10-01 13:25:49
User: brx75x
Functions: echo sleep
0
Up
Down
Create a continuous digital clock in Linux terminal

Same effect, only shell commands.

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for i in $(seq 1 100 | sort -R); do echo $i; sleep 5; done
2012-09-25 17:47:32
User: fernandomerces
Functions: echo seq sleep sort
Tags: sorting random bingo raffle
3
Up
Down
Bingo-like raffle

Random choose numbers from 1 to 100 with 5 seconds interval without duplicates.

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echo -e "\e[32m"; while :; do printf '%*c' $(($RANDOM % 30)) $(($RANDOM % 2)); done
2012-09-25 17:36:25
User: fernandomerces
Functions: echo printf
Tags: random Matrix
3
Up
Down
Binary digits Matrix effect

Prints 0's and 1's in The Matrix style. You can easily modify to print 0-9 digits using $RANDOM %10 insted of %2.

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echo $(</dev/urandom tr -dc 1-6 | head -c1)
2012-09-21 08:38:51
User: unixmonkey40000
Functions: echo head tr
Tags: password random /dev/random diceware
0
Up
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True Random Dice Roll
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echo $((0x$(head -c5 /dev/random|xxd -ps)%6+1))
2012-09-21 02:16:42
User: atoponce
Functions: echo head
Tags: password random /dev/random diceware
9
Up
Down
True Random Dice Roll

/dev/random is said to by cryptographically secure, and unpredictable, as it gathers data from external sources, influenced by human timing interactions with computers, to fill the entropy pool. As such, this is a quick way to do a true random fair-6 dice roll. Using this method, you could easily create passphrases with Diceware http://diceware.com.

for i in {1..5}; do echo -n $((0x$(head -c5 /dev/random|xxd -ps)%6+1)); done; echo
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( x=`tput op` y=`printf %$((${COLUMNS}-6))s`;for i in {0..256};do o=00$i;echo -e ${o:${#o}-3:3} `tput setaf $i;tput setab $i`${y// /=}$x;done; )
2012-09-18 11:23:46
User: mkfmn
Functions: echo tput
0
Up
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test console colors
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echo $(find <directory> -name '*.<extension>' -exec du -s {} \; | tee $(tty) | cut -f1 | tr '\n' '+') 0 | bc
2012-09-17 22:46:50
User: ysangkok
Functions: cut du echo find tee tr
Tags: find du tty-dependant
-1
Up
Down
Sum files of certain extension in given directory

Also shows files as they are found. Only works from a tty.

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i=0; while [ $i -lt 100 ]; do echo "test, ttest, tttest-${i}" >> kk.file; i=`expr $i + 1`; done
2012-09-13 21:46:18
User: kaushalmehra
Functions: echo
Tags: unix while loop for loop
-3
Up
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Generate a test csv file using looping in AIX

while commandt

do

command

command

...

done

{commandt is executed and its exit status tested.}

for i in 1 2 3

> do

> echo $i

> done

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for i in /sys/block/sd* ; do wwn=`/lib/udev/scsi_id -g -s /block/${i##*/}` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done
2012-09-12 14:14:53
User: mhs
Functions: echo
Tags: sysfs WWN LUNs scsi_id
1
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Formatted list - WWNs of all LUNs

Use `scsi_id` to positively identify which LUNs are which (i.e. compare with the list of LUNs you created on your disk array)

(shown: RHEL5 usage)

Debian usage:

# for i in /dev/sd* ; do wwn=`/lib/udev/scsi_id -g --device $i` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done
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avconv -i input.avi -target pal-dvd dvd.mpg && echo PAL > ~/.config/video_format && dvdauthor -o dvd/ -t dvd.mpg && dvdauthor -o dvd/ -T && growisofs -Z /dev/dvd -dvd-video dvd/
2012-09-09 20:56:54
User: ppq
Functions: echo
0
Up
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Burn a simple DVD-Video without menu using any given video file

This is the fastest way to burn a DVD-Video from the command line.

Dependencies:

libav-tools

dvdauthor

growisofs

The first command:

avconv -i input.avi -target pal-dvd dvd.mpg

converts any given video file avconv can handle into MPEG2-PS (6 Mbit/s) with AC3 audio (448 kbit/s). If your distribution is not up to date, just use ffmpeg - the syntax is the same. Hint: If you want to create an NTSC DVD, type ntsc-dvd instead ;-)

The second command:

echo PAL > ~/.config/video_format

sets PAL as your default video format. This is a workaround for an old dvdauthor bug. If you want NTSC, guess what? Type NTSC instead!

The third command:

dvdauthor -o dvd/ -t dvd.mpg

creates .VOB files and adds them to the dvd/ folder. You don't have to create this folder yourself. You can add as many titles as you like, just keep in mind that there's a maximum of 4482 MiB (4.37 GiB) for normal DVDs.

The fourth command:

dvdauthor -o dvd/ -T

finishes the DVD-Video.

Now you can burn your DVD using growisofs:

growisofs -Z /dev/dvd -dvd-video dvd/

Sources:

manpages

http://tuxicity.wordpress.com/2006/12/01/avi-to-dvd-with-ffmpeg-and-dvdauthor/

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apt-popcon() { (echo \#rank; apt-cache search "$@" |awk '$1 !~ /^lib/ {print " "$1" "}') |grep -Ff- <(wget -qqO- http://popcon.debian.org/by_inst.gz |gunzip); }
2012-09-08 00:29:31
User: khopesh
Functions: apt awk echo grep wget
Tags: Debian Ubuntu apt-cache
4
Up
Down
Search for packages, ranked by popularity

This will take the packages matching a given `apt-cache search` query (a collection of AND'd words or regexps) and tell you how popular they are. This is particularly nice for those times you have to figure out which solution to use for e.g. a PDF reader or a VNC client.

Substitute "ubuntu.com" for "debian.org" if you want this to use Ubuntu's data instead. Everything else will work perfectly.

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a=$(xwininfo |gawk 'BEGIN {FS="[x+ \t]*"} /-geometry/ {print int(($3+1)/2)*2"x"int(($4+1)/2)*2"+"$5"+"$6}') ; echo ${a} ; ffmpeg -f x11grab -s ${a} -r 10 -i :0.0 -sameq -f mp4 -s wvga -y /tmp/out.mpg
2012-08-31 14:48:41
User: dwygo
Functions: echo gawk
Tags: ffmpeg awk alsa xwininfo x11grab mp4 wvga
0
Up
Down
Capture screen and mic input using FFmpeg and ALSA

Now we can capture only a specific window (we have to chose by clicking on it)

ffmpeg complains about "Frame size must be a multiple of 2" so we calculate the upper even number with (g)awk trickery.

We remove the grep, we are already using (g)awk here ....why losing time with grep !!! ;)

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SUBNET="192.168.41" ; diff -y <(nmap -sP -n ${SUBNET}.0/24 | grep ${SUBNET}. | awk '{print $5}' | sort -t"." -k4 -n) <(for i in $(seq 1 254); do echo ${SUBNET}.$i; done)
2012-08-28 09:11:18
User: michel_p
Functions: awk diff echo grep seq sort
0
Up
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Look for free ip's in a given /24 subnet.

The command will make it easy to determine free IP ranges in a crowded sub-net.

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Q="Hello world"; GOOG_URL="http://www.google.com/search?q="; AGENT="Mozilla/4.0"; stream=$(curl -A "$AGENT" -skLm 10 "${GOOG_URL}\"${Q/\ /+}\"" | grep -oP '\/url\?q=.+?&amp' | sed 's/\/url?q=//;s/&amp//'); echo -e "${stream//\%/\x}"
2012-08-26 20:13:21
User: westeros91
Functions: echo grep sed
Tags: curl google
1
Up
Down
Search Google
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echo "" > filr.txt
2012-08-23 19:31:51
User: kalikid021
Functions: echo
-23
Up
Down
Empty a file
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echo 'main(t){for(;;t++)putchar(((t<<1)^((t<<1)+(t>>7)&t>>12))|t>>(4-(1^7&(t>>19)))|t>>7);}' | cc -x c - -o crowd && ./crowd | aplay
2012-08-22 10:15:27
User: mx4492
Functions: cc echo
Tags: music aplay bytebeat
0
Up
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Bytebeat

Never ending music, generated via a C snippet, piped to aplay. Taken from: http://canonical.org/~kragen/bytebeat/

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echo -e "`curl -sL http://www.commandlinefu.com/commands/random/json|sed -re 's/.*,"command":"(.*)","summary":"([^"]+).*/\\x1b[1;32m\2\\n\\n\\x1b[1;33m\1\\x1b[0m/g'`\n"
2012-08-17 11:47:20
User: xenomuta
Functions: echo
Tags: login random random commands commandlinefu.com
4
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Show a random oneliner from commandlinefu.com

This will parse a random command json entry from http://commandlinefu.com

A must have in your .bash_profile to learn new shell goodies at login!!!

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centralized(){ L=`echo -n $*|wc -c`; echo -e "\x1b[$[ ($COLUMNS / 2) - ($L / 2) ]C$*"; }
2012-08-16 18:19:26
User: xenomuta
Functions: echo wc
Tags: echo ansi
0
Up
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Output centralized text on command line

Echoes text horizontally centralized based on screen width

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