Commands using echo | commandlinefu.com

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Terminal - Commands using echo - 1,221 results

touch /tmp/$$;for N in `seq -w 0 7777|grep -v [89]`; do chmod $N /tmp/$$; P=`ls -l /tmp/$$ | awk '{print $1}'`; echo $N $P; done;rm /tmp/$$

2009-03-05 15:24:41

User: jyoder

Functions: awk chmod echo touch

Up
Down

Create a listing of all possible permissions and their octal representation.

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo Print text vertically|sed 's/$.$/\1\n/g'

2009-03-04 23:58:02

User: axelabs

Functions: echo

Tags: sed echo pipe

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Print text string vertically, one character per line.

dpkg --compare-versions 1.0-2ubuntu5 lt 1.1-1~raphink3 && echo y || echo n

2009-02-28 18:01:59

User: raphink

Functions: echo

Tags: Debian Ubuntu

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Know which version dpkg/apt considers more recent

Compares two versions with dpkg. It is not always obvious what version dpkg/apt will consider to be more recent. Operators include the following :

* These treat an empty version as earlier than any version: lt le eq ne ge gt.

* These treat an empty version as later than any version: lt-nl le-nl ge-nl gt-nl.

* These are provided only for compatibility with control file syntax: < > >.

This command doesn't output anything. It only returns with status 0 or 1, hence the echo "y" || echo "n" to get an output.

for vm in $(vmware-cmd -l);do echo -n "${vm} ";vmware-cmd ${vm} getstate|awk '{print $2 " " $3}';done

2009-02-26 16:45:04

User: dbart

Functions: echo

Tags: VMware Server Linux

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VMware Server print out the state of all registered Virtual Machines.

I use this command on my machines running VMware Server to print out the state of all registered Virtual machines.

echo COMMAND | xargs -ixxx ps -C xxx -o pid= | xargs -ixxx ls -l /proc/xxx/cwd

2009-02-25 05:49:03

User: ento

Functions: echo ls ps xargs

Tags: Process Management

Up
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Find out current working directory of a process

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo "!!" > foo.sh

2009-02-25 00:37:25

User: dnavarre

Functions: echo

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Create a script of the last executed command

Sometimes commands are long, but useful, so it's helpful to be able to make them permanent without having to retype them. An alternative could use the history command, and a cut/sed line that works on your platform.

history -1 | cut -c 7- > foo.sh

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declare -i aa ; aa=3*8 ; echo $aa

2009-02-24 21:58:13

User: jcgam69

Functions: echo

-3

Up
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declare variable as integer

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OLD_IFS="$IFS"; IFS=: ARRAY=($PATH); echo ${ARRAY[2]}; IFS="$OLD_IFS"

2009-02-22 11:40:49

User: mikeda

Functions: echo

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split a string (3)

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echo *.log | xargs <command>

2009-02-22 11:32:55

User: mikeda

Functions: echo xargs

Up
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for too many arguments by *

grep ERROR *.log

-bash: /bin/grep: Argument list too long

echo *.log | xargs grep ERROR /dev/null

20090119.00011.log:DANGEROUS ERROR

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

read VAR1 VAR2 VAR3 < <(echo aa bb cc); echo $VAR2

2009-02-22 10:05:50

User: mikeda

Functions: echo read

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split a string (2)

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

2009-02-21 15:55:37

User: magictoken

Functions: bc cut echo sed tr

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memcache affinity: queries local memcached for stats, calculates hit/get ratio and prints it out.

queries local memcached for stats, calculates hit/get ratio and prints it out.

doloop() { DONT=/tmp/do-run-run-run; while true; do touch $DONT; (sleep 30; rm $DONT;) & $1 ; if [ -e $DONT ]; then echo restarting too fast; return ; fi ; done }

2009-02-21 02:11:18

User: evil_otto

Functions: echo return rm sleep touch

-1

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run a command repeatedly

This runs a command continuously, restarting it if it exits. Sort of a poor man's daemontools. Useful for running servers from the command line instead of inittab.

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HOST=127.0.0.1;for((port=1;port<=65535;++port)); do echo -en "$port ";if echo -en "open $HOST $port\nlogout\quit" | telnet 2>/dev/null | grep 'Connected to' > /dev/null; then echo -en "\n\nport $port/tcp is open\n\n";fi;done | grep open

2009-02-20 21:51:03

User: chrisclymer

Functions: echo grep telnet

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Scans for open ports using telnet

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echo "hello world" | festival --tts

2009-02-20 14:00:50

User: jacquesloonen

Functions: echo

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Synthesize text as speech

The Festival Speech Synthesis System converts text into sound.

Or: links -dump http://youfavoritewebsite.com | festival --tts

FLOOR=0; RANGE=10; number=0; while [ "$number" -le $FLOOR ]; do number=$RANDOM; let "number %= $RANGE"; done; echo $number

2009-02-20 09:33:56

User: raphink

Functions: echo

Tags: bash

-1

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Random integer number between FLOOR and RANGE

This one-liner outputs a random number between the values given for FLOOR and RANGE.

/lib/ld-linux.so.2 =(echo -e '#include <stdio.h>\nint main(){printf("c one liners\\n");}' | gcc -x c -o /dev/stdout -)

2009-02-20 06:06:29

User: mrtheplague

Functions: c++ echo gcc

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C one-liners

/lib/ld-linux.so.2

is the runtime linker/loader for ELF binaries on Linux.

=(cmd) is a zsh trick to take the output for the command "inside" it and save it to a temporary file.

echo -e 'blah' | gcc -x c -o /dev/stdout -

pipes the C source to gcc. -x c tells gcc that it's compiling C (which is required if it's reading from a pipe). -o /dev/stdout - tells it to write the binary to standard output and read the source from standard input.

because of the the =() thing, the compiled output is stashed in a tempfile, which the loader then runs and executes, and the shell tosses the tempfile away immediately after running it.

echo 1 > /proc/sys/kernel/sysrq; echo b > /proc/sysrq-trigger

2009-02-20 00:37:18

User: tsaavik

Functions: echo

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Force machine to reboot no matter what (even if /sbin/shutdown is hanging)

This will cause your machine to INSTANTLY reboot. No un-mounting of drives or anything.

Very handy when something has gone horribly wrong with your server in that co-location facility miles away with no remote hands!

Suspect this works with all 2.2, 2.4 and 2.6 Linux kernels compiled with magic-syskey-request support.

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for i in `recode -l | cut -d" " -f 1`; do echo $i": ?" | recode utf-8..$i -s -p >> temp; done; vim temp

2009-02-20 00:14:33

User: saerdnaer

Functions: cut echo vim

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List encoding of ? in all avalible char sets

If you have some textfile with an unknown encoding you can use this list to find out

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check_disk -w 15% -c 10% $(for x in $(cat /proc/mounts |awk '{print $2}')\; do echo -n " -p $x "\; done)

2009-02-19 22:54:06

User: scubacuda

Functions: cat echo

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checking space availabe on all /proc/mounts points (using Nagios check_disk)

More info here: http://nagioswiki.com/wiki/index.php/Checking_/proc/mounts_on_remote_server

while read line; do echo "$(date),$(hostname),$line"; done < somefile.txt

2009-02-19 18:48:12

User: nottings

Functions: echo read

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read a file line by line and perform some operation on each line

see sample output

while [ 0 ]; do echo -e "HTTP/1.1 302 Found\nLocation: http://www.whatevs.com/index.html" | nc -vvvv -l -p 80; done

2009-02-19 18:04:01

User: wwest4

Functions: echo

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HTTP redirect

any HTTP requests to the machine on the specified port will be redirected to http://www.whatevs.com... quick, dirty, works fine for sites w/

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo "8000000/(20*6*86400)" | bc -l

2009-02-19 17:05:20

User: skygreg

Functions: bc echo

Up
Down

doing some floating point math

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echo -ne "\033]0;${USER}@${HOSTNAME}: ${PWD}\007"

2009-02-19 14:15:31

User: stinger

Functions: echo

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auto terminal title change

above line in .bash_profile will give you window title in putty or terminal client when you login to your remote server

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echo 1+1|bc

2009-02-19 13:46:58

User: gnawa

Functions: echo

-5

Up
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doing some math...

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while true; do read i; echo $[$i]; done

2009-02-18 23:13:09

User: mulad

Functions: echo read

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Simple calculator

The $[...] block in bash and zsh will let you do math.

echo $[6*7]

This is the same as using $((...)), which also works in ksh. Of course, this is a simple, dumb wrapper and doesn't allow floating-point.

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