Commands using echo sorted by votes

Commands using echo (1,545)

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Python version to a file

This command sent the Python version to a file. This is intended to be used in scripts. For some reason, simple redirections didn't work with "python -V" Show Sample Output
This is sample output - yours may be different.
```
cat file
Python 2.6.3
```
0

echo "$(python -V 2>&1)" > file

x3mboy · 2018-11-06 20:52:49 438
Generate a sequence of numbers.
This is sample output - yours may be different.
0

echo {1..99}

wolfpup · 2018-11-11 01:04:22 590
Generate a sequence of numbers.

Uses bash shortcut to generate series, it works with letters too echo {A..H} echo {a..h} Be careful not to mix upper and lower case, you may encounter funny results : echo {z..A} z y x w v u t s r q p o n m l k j i h g f e d c b a ` _ ^ ] [ Z Y X W V U T S R Q P O N M L K J I H G F E D C B A Show Sample Output
This is sample output - yours may be different.
```
1 2 3 4 5 6 7 8 9 10 11 12
```
0

echo {1..12}

keltroth · 2018-11-12 14:09:26 367
converts all pngs in a folder to webp, quality can be choosed as a argument

needs cwebp
This is sample output - yours may be different.
0

pngwebp(){ arg1=$1 for i in *.png; do name=`echo "${i%.*}"`; echo $name; cwebp -q $1 "${i}" -o "${name}.webp" done }

k2arim99 · 2018-12-01 14:38:05 898
OSX script to change Terminal profiles based on machine name; use with case statement parameter matching

/macos/mojave shell script to change terminal profiles
This is sample output - yours may be different.
0

echo "tell application \"Terminal\"\n\t set its current settings of selected tab of window 1 to settings set \"$PROFILE\"\n end tell"|osascript;

christoph000 · 2018-12-19 23:48:12 34
check web server port 80 response header

check web server port 80 response header Show Sample Output
This is sample output - yours may be different.
```
HTTP/1.1 200 OK
Server: Apache 2.4.1
Date: Wed, 17 Apr 2019 17:56:50 GMT
Content-Type: text/html
Content-Length: 307
Last-Modified: Sat, 14 Jan 2017 22:01:22 GMT
Connection: close
ETag: "587a9fb2-133"
X-Frame-Options: SAMEORIGIN
Accept-Ranges: bytes
```
0

(echo -e 'GET / HTTP/1.0\r\n\r\n';) | ncat <IPaddress> 80

aysadk · 2019-04-17 18:09:28 34
Random number with a normal distribution between 1 and X

Print a random number between 1 and 50 with a normal distribution around the center. The numbers around the middle are the most likely to occur and the farther you get from that the less and less common they are. You can test this and observe the number distribution with this command: for i in `seq 100000`; do echo $[(${RANDOM}%40+${RANDOM}%40)/2+1]; done | sort -n | uniq -c Show Sample Output
This is sample output - yours may be different.
```
30
```
0

echo $[(${RANDOM}%100+${RANDOM}%100)/2+1]

varenc · 2019-05-16 00:58:25 40
automatically generate the ip/hostname entry for the /etc/hosts in the current system

I use it after a clean CentOS 7 minimal server installation to automatically populate the /etc/hosts file. Not sure why the installation does not add this entry by itself. Tested on CentOS 7 with the simplest use case: 1 static ip address and the hostname provided during installation. Show Sample Output
This is sample output - yours may be different.
```
[root@dns-server ~]# echo "$(ip addr show dev $(ip r | grep -oP 'default.*dev \K\S*') | grep -oP '(?<=inet )[^/]*(?=/)') $(hostname -f) $(hostname -s)"
10.0.2.10 dns-server.mydomain.lab dns-server

[root@dns-server ~]# echo "$(ip addr show dev $(ip r | grep -oP 'default.*dev \K\S*') | grep -oP '(?<=inet )[^/]*(?=/)') $(hostname -f) $(hostname -s)" >> /etc/hosts

[root@dns-server ~]# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
10.0.2.10 dns-server.mydomain.lab dns-server
```
0

echo "$(ip addr show dev $(ip r | grep -oP 'default.*dev \K\S*') | grep -oP '(?<=inet )[^/]*(?=/)') $(hostname -f) $(hostname -s)"

acavagni · 2019-06-15 16:40:38 42
Set user password without passwd
This is sample output - yours may be different.
0

echo 'user:newpassword' | chpasswd

wuseman1 · 2019-07-06 23:58:47 40
Download certificate from FTP
This is sample output - yours may be different.
0

echo | openssl s_client -servername ftp.domain.com -connect ftp.domain.com:21 -starttls ftp 2>/dev/null | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p'

Raboo · 2019-07-19 12:30:19 198
pretty print json block that has quotes escaped
This is sample output - yours may be different.
0

echo 'json_here' | sed 's/\\//g' | jq .

jgleeson · 2019-07-19 16:26:48 313
bash test check validate if variable is number

to test check if given variable is a digit / number Show Sample Output
This is sample output - yours may be different.
```
error: Not a number
```
0

varNUM=12345; re='^[0-9]+$'; if ! [[ $varNUM =~ $re ]] ; then echo "error: Not a number"; fi

aysadk · 2019-07-26 09:15:37 403
Check whether laptop is running on battery or cable

Just an alternative for `acpi -b` Show Sample Output
This is sample output - yours may be different.
```
Discharging 46%
```
0

eval "$(printf "echo %s \$((%i * 100 / %i))\n" $(cat $(find /sys -name energy_now 2>/dev/null | head -1 | xargs dirname)/{status,energy_{now,full}}))%"

glaudiston · 2019-08-10 16:50:12 598
Print all git repos from a user

Python is installed on many boxes (in case you could not afford installing jq).
This is sample output - yours may be different.
0

curl -s "https://api.github.com/users/<username>/repos?per_page=1000" | python <(echo "import json,sys;v=json.load(sys.stdin);for i in v:; print(i['git_url']);" | tr ';' '\n')

grault · 2019-12-07 10:49:58 106

List SAN Domains for a certificate Show Sample Output

echo | openssl s_client -connect google.com:443 2>&1 | openssl x509 -noout -text | awk -F, -v OFS="\n" '/DNS:/{x=gsub(/ *DNS:/, ""); $1=$1; print $0}'

shadyabhi · 2020-04-10 06:56:51 88

From all PDF files in all subdirectories, extract two metadata fields (here: Creator and Producer) into a CSV table
This is sample output - yours may be different.
0

echo "File;Creator;Producer";find . -name '*.pdf' -print0 | while IFS= read -d $'\0' line;do echo -n "$line;";pdfinfo "$line"|perl -ne 'if(/^(Creator|Producer):\s*(.*)$/){print"$2";if ($1 eq "Producer"){exit}else{print";"}}';echo;done 2>/dev/null

langec · 2020-12-17 21:08:55 1140
Remove all the characters after last space per line including it

It his example removes ' dog', last space included. Show Sample Output
This is sample output - yours may be different.
```
The quick brown fox jumps over the lazy
```
0

echo 'The quick brown fox jumps over the lazy dog' | sed 's|$.*$ .*|\1|'

bugmenot · 2021-07-15 20:01:32 168
Clear Cached Memory on Ubuntu

Clear Cached Memory on Ubuntu based distributions, and also display memory status. Please do not use this on a production machine unless you really really know what you are doing. Echo 3 is a kinder way of purging the memory, you can also use 'echo 2' or 'echo 1' if #1 You know what you are doing, and #2 refer to number 1 :-)
This is sample output - yours may be different.
0

sudo free && sync && sudo echo 3 | sudo tee /proc/sys/vm/drop_caches

tg0000 · 2021-09-13 16:45:20 568
Infinite loop ssh

Useful when you wait for a server to boot up.
This is sample output - yours may be different.
0

while true; do ssh login@10.0.0.1; if [[ $? -ne 0 ]]; then echo "Nope, keep trying!"; fi; sleep 10; done

FluffyBrick · 2021-09-29 12:54:17 320
a pseudo-random coin flip in python
This is sample output - yours may be different.
-1

echo "import random; print(random.choice(['heads', 'tails']))" | python

ag3ntj0n · 2009-02-05 21:01:01 30
To generate the list of dates using bash shell
This is sample output - yours may be different.
-1

now=`date +"%Y/%m/%d" -d "04/02/2005"` ; end=`date +"%Y/%m/%d" -d "07/31/2005"`; while [ "$now" != "$end" ] ; do now=`date +"%Y/%m/%d" -d "$now + 1 day"`; echo "$now"; done

mnikhil · 2009-02-07 18:46:49 12
use perl instead of sed

Replace sed regular expressions with perl patterns on the command line. The sed equivalent is: echo "sed -e"|sed -e 's/sed -e/perl -pe/' Show Sample Output
This is sample output - yours may be different.
```
[root@bigdaddy ~]# echo "sed -e"|perl -pe 's/sed -e/perl -pe/'
perl -pe
```
-1

echo "sed -e"|perl -pe 's/sed -e/perl -pe/'

drossman · 2009-02-16 18:39:06 836
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
This is sample output - yours may be different.
```
6
```
-1

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

raphink · 2009-02-20 09:33:56 13
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.
This is sample output - yours may be different.
-1

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 }

evil_otto · 2009-02-21 02:11:18 5
Easily create and share X screen shots (remote webserver version)

Here $HOME/shots must exist and have appropriate access rights and sitecopy must be correctly set up to upload new screen shots to the remote site. Example .sitecopyrc (for illustration purposes only) site shots server ftp.example.com username user password antabakadesuka local /home/penpen/shots remote public_html/shots permissions ignore The command uses scrot to create a screen shot, moves it to the screen shot directory, uploads it using screen uses xsel to copy the URL to the paste buffer (so that you can paste it with a middle click) and finally uses feh to display a preview of the screen shot. Note that $BASE stands for the base URL for the screen shots on the remote server, replace it by the actual location; in the example http://www.example.com/~user/shots would be fitting. Assign this command to a key combination or an icon in whatever panel you use. Show Sample Output
This is sample output - yours may be different.
```
sitecopy: Updating site `shots' (on ftp.example.com in public_html/shots/)
Uploading 2009-03-26-125223_1280x1024_scrot.png: [..............] done.
sitecopy: Update completed successfully.
```
-1

scrot -e 'mv $f \$HOME/shots/; sitecopy -u shots; echo "\$BASE/$f" | xsel -i; feh `xsel -o`'

penpen · 2009-03-26 12:08:39 4
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Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Sort on multiple dis-contiguous keys/fields (can even specify key number/field from the end)

Notes: 1) -n-1 means sort key is the last field 2) -l is important if each separate record is on a new line (usually so for text files) 3) -j tells msort not to create log file (msort.log) in the working directory 4) may need to install msort package. 5) msort does lot more. Check man msort

copy audio file from playlist to a floder

copy some file from xx.m3u to target folder

Run a ext4 file system check and badblocks scan with progress info

Nothing fancy, just a regular filesystem scan that calls the badblocks program and shows some progress info. The used options are: -c ? check for bad sectors with badblocks program -D ? optimize directories if possible -f ? force check, even if filesystem seems clean -t ? print timing stats (use -tt for more) -y ? assume answer ?yes? to all questions -C 0 ? print progress info to stdout /dev/sdxx ? the partition to check, (e.g. /dev/sda1 for first partition on first hard disk) NOTE: Never run fsck on a mounted partition!

sort ugly text

Often, when sorting you want the sort to ignore extraneous characters. The b, d, and f tell sort to ignore leading blanks, use 'dictionary order' (ignore punctuation), and ignore (fold) case. Add a "u" if you only want one copy of duplicate lines. This is a great command to use within vim to sort lines of text, using !}sort -bdf

Force the script to be started as root

Will run the script as root and exit if the wrong or no password is given. Also will keep the parameters active if any where given.

Recursive Line Count

Download a numbered sequence of files

Anti Syn Ddos

Ddos syn attack

detect the fastest ldap server on a intranet

This command line detect ldap hosts, by mandatory dns entry, then ping them to detect response average. based on ping response average it sorts and print the faster server in first output line

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Commands using echo (1,545)

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