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Commands using echo

Commands using echo from sorted by
Terminal - Commands using echo - 1,115 results
OLD_IFS="$IFS"; IFS=: ARRAY=($PATH); echo ${ARRAY[2]}; IFS="$OLD_IFS"
2009-02-22 11:40:49
User: mikeda
Functions: echo
2
Up
Down
split a string (3)
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo *.log | xargs <command>
2009-02-22 11:32:55
User: mikeda
Functions: echo xargs
5
Up
Down
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
7
Up
Down
split a string (2)
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo -en "stats\r\n" "quit\r\n" | nc localhost 11211 | tr -s [:cntrl:] " "| cut -f42,48 -d" " | sed "s/\([0-9]*\)\s\([0-9]*\)/ \2\/\1*100/" | bc -l
2009-02-21 15:55:37
User: magictoken
Functions: bc cut echo sed tr
3
Up
Down
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.

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
Down
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
2
Up
Down
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
7
Up
Down
Synthesize text as speech

The Festival Speech Synthesis System converts text into sound.

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

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
Down
Random integer number between FLOOR and RANGE

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

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
/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
6
Up
Down
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.

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo 1 > /proc/sys/kernel/sysrq; echo b > /proc/sysrq-trigger
2009-02-20 00:37:18
User: tsaavik
Functions: echo
7
Up
Down
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
0
Up
Down
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
4
Up
Down
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

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while read line; do echo "$(date),$(hostname),$line"; done < somefile.txt
2009-02-19 18:48:12
User: nottings
Functions: echo read
2
Up
Down
read a file line by line and perform some operation on each line

see sample output

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
4
Up
Down
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/

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echo "8000000/(20*6*86400)" | bc -l
2009-02-19 17:05:20
User: skygreg
Functions: bc echo
2
Up
Down
doing some floating point math
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sync && echo 3 > /proc/sys/vm/drop_caches
2009-02-19 15:54:22
User: skygreg
Functions: echo sync
3
Up
Down
Empty the linux buffer cache
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echo -ne "\033]0;${USER}@${HOSTNAME}: ${PWD}\007"
2009-02-19 14:15:31
User: stinger
Functions: echo
1
Up
Down
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
Down
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
0
Up
Down
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.

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
for (( i = 10; i > 0; i-- )); do echo "$i"; sleep 1; done
2009-02-18 20:31:46
User: mestr
Functions: echo sleep
4
Up
Down
Count down from 10

Countdown from 10 or whatever you want:)

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
unset files i; set -f; O=$IFS; while IFS= read -r -d $'\0' files[i++]; do :; done < <(find . -name '*.avi' -print0) && IFS=$O; set +f && echo "Running: mplayer \"${files[ $(( $RANDOM % ${#files[@]} )) ]}\""
2009-02-18 16:53:57
User: DEinspanjer
Functions: echo find read set unset
0
Up
Down
Play a random .avi file from a media tree

unsets variables used by the one-liner

sets up the IFS bash variable to not be affected by whitespace and disables extra glob expansion

uses read to slurp the results of the find command into an array

selects an element of the array at random to be passed as an argument to mplayer

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "foo bar" | sudo tee -a /path/to/some/file
2009-02-18 13:54:25
User: raphink
Functions: echo sudo tee
Tags: Text Processing tee
3
Up
Down
Add a line to a file using sudo

This is the solution to the common mistake made by sudo newbies, since

sudo echo "foo bar" >> /path/to/some/file

does NOT add to the file as root.

Alternatively,

sudo echo "foo bar" > /path/to/some/file

should be replaced by

echo "foo bar" | sudo tee /path/to/some/file

And you can add a >/dev/null in the end if you're not interested in the tee stdout :

echo "foo bar" | sudo tee -a /path/to/some/file >/dev/null
Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "^[]0;My_Title_Goes _Here^G"
2009-02-17 20:46:06
User: TheNomad
Functions: echo
5
Up
Down
Change the window title of your xterm

If you are using an xterm emulation capable terminal emulator, such as PuTTY or xterm on Linux desktop, this command will replace the title of that terminal window. I know it is not nice to have seventeen terminals on your desktop with title PuTTY, you can not tell which one is connected to which server and doing what.

Even though the string between the quotes is typed as literals, it needs a little more finesse to make it work. Here is how it is done key-by-key:

echo "( ctrl-v then ctrl-[ )0;Enter_Title_String_Here( ctrl-v then ctrl-g )"( enter )

ctrl-v : means hold down ctrl key and hit v at the same time like you are pasting in windoze ; also please don't type the parentheses, i.e., ( and )

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echo $RANDOM
2009-02-17 14:41:06
User: mikeda
Functions: echo
2
Up
Down
generate random number
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echo foo bar foobar barfoo && echo !$ !^ !:3 !* && echo /usr/bin/foobar&& echo !$:h !$:t
2009-02-17 09:10:17
User: lhb
Functions: echo
10
Up
Down
bash shortcut: !$ !^ !* !:3 !:h and !:t

When expanding, bash output the command, so don't be affraid if you type the command.

Here is the details:

First examples:

echo foo bar foobar barfoo

First argument:

echo !$

echo barfoo

barfoo

(Note that typing echo foo bar foobar barfoo && echo !$, bash substitute !$ with $:1)

Last argument:

echo foo bar foobar barfoo && echo !^

echo foo bar foobar barfoo && echo barfoo

foo bar foobar barfoo

barfoo

All the arguments:

echo !*

echo foo bar foobar barfoo

foo bar foobar barfoo

The third argument:

echo foo bar foobar barfoo && echo !:3

echo foo bar foobar barfoo && echo foobar

foo bar foobar barfoo

foobar

You may want to add {} for large numbers: echo !:{11} for example

Now with path:

echo /usr/bin/foobar

/usr/bin/foobar

For the head:

echo !$:h

echo /usr/bin

/usr/bin

And the tail:

echo !$:t

echo foobar

foobar

You also may want to try !:h and !:t or !!3-4 for the third and the fourth (so !!:* == !!:1-$)

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