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Commands tagged random from sorted by
Terminal - Commands tagged random - 76 results
TMPFILE="/tmp/$RANDOM$RANDOM$RANDOM$RANDOM$RANDOM" && arecord -d 1 -t raw -f cd -q | base64 > $TMPFILE && pwgen -ys 12 12 -H $TMPFILE $@ && rm $TMPFILE
2014-06-09 16:28:41
User: juliohm
Functions: arecord cd rm
0

Generate a truly random password using noise from your microphone to seed the RNG. This will spit out 12 password with 12 characters each, but you can save this into a bash script and replace 'pwgen -ys 12 12' with 'pwgen $@' so you can pass any paramters to pwgen as you would normally do.

cat /dev/urandom | env LC_CTYPE=C tr -dc a-zA-Z0-9 | head -c 16; echo
2014-02-05 15:04:07
User: yakovlev
Functions: cat env head tr
0

Feel free to put this in your ~/.profile:

random(){ cat /dev/urandom | env LC_CTYPE=C tr -dc $1 | head -c $2; echo; }

Then use it to generate passwords:

random [:alnum:] 16

Or DNA sequences:

random ACGT 256
find . -iname "*.mp3" | mpg123 -Z --list -
base64 /dev/urandom | head -c 33554432 | split -b 8192 -da 4 - dummy.
9

Avoiding a for loop brought this time down to less than 3 seconds on my old machine. And just to be clear, 33554432 = 8192 * 4086.

for i in {1..4096}; do base64 /dev/urandom | head -c 8192 > dummy$i.rnd ; done
1

Using the 'time' command, running this with 'tr' took 28 seconds (and change) each time but using base64 only took 8 seconds (and change). If the file doesn't have to be viewable, pulling straight from urandom with head only took 6 seconds (and change)

for i in `seq 1 4096`; do tr -dc A-Za-z0-9 </dev/urandom | head -c8192 > dummy$i.rnd; done
yes 'echo $(( RANDOM%100+1 )); sleep 5' | bash
2013-11-09 16:22:59
User: stx
Functions: sleep yes
0

This one is for OS X users: sort -R and shuf aren't available in Lion (10.7.5)

yes 'c=(" " " " " " 0 1); printf "${c[RANDOM%5]}"' | bash
head -c 24 /dev/urandom | base64
2013-09-28 16:32:47
User: henix
Functions: head
Tags: random
0

Use less random number resources and less commands

od -An -N1 -tu1 /dev/random
2013-09-10 08:57:16
User: sucotronic
Functions: od
6

It takes a byte from /dev/random whose source is the kernel entropy pool (better source than other solutions).

echo -e "\e[3$(( $RANDOM * 6 / 32767 + 1 ))mHello World!"
2013-07-28 13:01:12
User: nst
Functions: echo
Tags: bash color random
0

The expression $(( $RANDOM * 6 / 32767 + 1 )) generates a random number between 1 and 6, which is then inserted into the escape sequence \e[3_m to switch the foreground color of the terminal to either red, green, yellow, blue, purple or cyan.

The color can be reset using the escape sequence \e[0m.

The full list of colors can be found here: https://wiki.archlinux.org/index.php/Color_Bash_Prompt#List_of_colors_for_prompt_and_Bash

echo $[RANDOM % 2]
echo $[RANDOM % 100] # range 0-99
2013-05-25 19:02:00
User: anapsix
Functions: echo
-2

use it to stagger cronjob or to get a random number

increase the range by replacing 100 with your own max value

echo -e "CHECK=SAMPLE" output --command_to_long
2013-04-03 08:46:47
User: techie
Functions: echo
-1

This is longer than others on here. The reason for this is I have combined two different matrix commands so it would work on all computers. I logged onto my server through a computer and it worked fine. I logged into my server through a mac and it looked $4!t so I have made one that works through both.

while true; do printf "\e[32m%X\e[0m" $((RANDOM%2)); for ((i=0; i<$((RANDOM%128)); i++)) do printf " "; done; done
2012-11-27 10:40:42
User: seb1245
Functions: printf
0

Unlike other alternatives, this command only relies on bash builtins and should also work on windows platforms with the bash executable.

Sparseness corresponds to the number 128 and can be adjusted. To print all possible digits instead of only 0 and 1 replace RANDOM%2 by RANDOM%10 or RANDOM%16 to add letters [A-F].

perl -e '$|++; while (1) { print " " x (rand(35) + 1), int(rand(2)) }'
for i in $(seq 1 100 | sort -R); do echo $i; sleep 5; done
2012-09-25 17:47:32
Functions: echo seq sleep sort
3

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

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

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.

echo $(</dev/urandom tr -dc 1-6 | head -c1)
echo $((0x$(head -c5 /dev/random|xxd -ps)%6+1))
2012-09-21 02:16:42
User: atoponce
Functions: echo head
9

/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
for i in $(wget -O- -U "" "http://wallbase.cc/random/23/e..." --quiet|grep wallpaper/|grep -oe 'http://wallbase.cc[^"]*'); do wget $(wget -O- -U "" $i --quiet|grep -oe 'http://[^"]*\.jpg');done
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
4

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!!!

cat /dev/urandom|od -t x1|awk 'NR > line { pos=int(rand()*15)+2;printf("%s",$pos);line=NR+(rand()*1000);digits = digits+2 } digits == 64 { print("\n");exit }'
2012-08-14 19:02:00
User: jetdillo
Functions: awk cat exit od
1

Use this the next time you need to come up with a reasonably random bitstring, like for a WPA/WPA2 PSK or something. Takes a continuous stream of bytes coming from /dev/urandom, runs it through od(1), picking a random field ($0 and $1 excluded) from a random line and then prints it.

perl -e 'printf "00:16:3E:%02X:%02X:%02X\n", rand 0xFF, rand 0xFF, rand 0xFF'
false; while [ $? != 0 ]; do apg -c /dev/urandom -n1 -E oOlL10 | egrep '^[[:alnum:]]+$'; done