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Commands tagged random from sorted by
Terminal - Commands tagged random - 79 results
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

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
ls | grep -i mp3 | sort -R | sed -e 's/.*/"&"/' | xargs mpg123
2012-03-10 20:51:36
User: retrodanny
Functions: grep ls sed sort xargs

* grep -i leaves only mp3 files (case insentitive)

* sort -R randomizes list (may use GNU 'shuf' instead).

* the sed command will add double quotes around each filename (needed if odd characters are present)

genRandomText() { x=({a..z}); for(( i=0; i<$1; i++ )); do printf ${x[$((RANDOM%26))]}; done; printf "\n"; }
2012-01-26 08:19:33
User: uxseven
Functions: printf

Here's my version. It's a bit lengthy but I prefer it since it's all Bash.

genRandomText() { cat /dev/urandom|tr -dc 'a-zA-Z'|head -c $1 }
2012-01-21 00:51:34
User: thomasba
Functions: cat head tr
Tags: random urandom

Using urandom to get random data, deleting non-letters with tr and print the first $1 bytes.

genRandomText() { perl -e '$n=shift; print chr(int(rand(26)) + 97) for 1..$n; print "\n"' $1;}
2012-01-21 00:21:20
User: putnamhill
Functions: perl

If you don't have seq, you can use perl.

genRandomText() { a=( a b c d e f g h i j k l m n o p q r s t u v w x y z );f=0;for i in $(seq 1 $(($1-1))); do r=$(($RANDOM%26)); if [ "$f" -eq 1 -a $(($r%$i)) -eq 0 ]; then echo -n " ";f=0;continue; else f=1;fi;echo -n ${a[$r]};done;echo"";}
2012-01-20 21:18:16
User: bbbco
Functions: echo seq

Ever need to get some text that is a specific number of characters long? Use this function to easily generate it! Doesn't look pretty, but sure does work for testing purposes!

sort --random-sort file
2011-12-10 20:28:54
User: arld101
Functions: sort
Tags: sort random

Seeing that _sort_ its been used, why not just _use_ it. ;)

pwgen 30 1
2011-07-24 19:43:48
User: sairon

The pwgen program generates passwords which are designed to be easily memorized by humans, while being as secure as possible. Human-memorable passwords are never going to be as secure as completely completely random passwords. [from pwgen man page]

gpg --gen-random --armor 1 30
2011-07-20 15:32:49
User: atoponce
Functions: gpg

According to the gpg(1) manual:

--gen-random 0|1|2 count

Emit count random bytes of the given quality level 0, 1 or 2. If count is not given or zero, an endless sequence of random bytes will be emitted. If used with --armor the output will be base64 encoded. PLEASE, don't use this command unless you know what you are doing; it may remove precious entropy from the system!

If your entropy pool is critical for various operations on your system, then using this command is not recommended to generate a secure password. With that said, regenerating entropy is as simple as:

du -s /

This is a quick way to generate a strong, base64 encoded, secure password of arbitrary length, using your entropy pool (example above shows a 30-character long password).

rf() { for i in "$@"; do mv "$i" "$(pwgen 8 1).${i##*.}"; done }
2011-06-22 07:45:23
User: flatcap
Functions: mv

Give files a random name (don't ask why :-)

The function will rename files but maintain their extensions.

BUG: If a file doesn't have an extension it will end up with a dot at the end of the name.

The parameter '8' for pwgen controls the length of filenames - eight random characters.

find . | shuf -n1
shuf -n1 -e *
a=(*); echo ${a[$((RANDOM % ${#a[@]}))]}
for i in *; do echo "$i"; done | shuf -n1
2011-03-17 17:48:42
User: johnraff
Functions: echo
Tags: bash random

Choose random file from current folder. Avoids using ls.

mplayer "$(find . -maxdepth 2 -mindepth 2 -type d | grep -v '^.$' | sort -R | head -n1)"/*
2011-03-15 01:19:59
User: jedahan
Tags: music random

Good if you have your music like Artist/(Year) Album/Song

ls -1 | shuf -n 1
echo Selected $(ls -1 | sort -R | head -n 1)
IFS=$'\n'; LIST=`ls -1`; let TOT=`echo $LIST | wc -w`-1 ; array=($LIST); echo "Selected ${array[ ($RANDOM % $TOT) ]}"
2011-03-13 21:30:44
User: ntropia
Functions: echo wc
Tags: bash random

The same thing using only Bash built-in's.

For readability I've kept the variables out, but it could me made extremely more compact (and totally unreadable!) by stuffing everything inside the single echo command.

ls -1 | sort -R | sed -n 's/^/Selected /;1p'
ls -1 | awk 'BEGIN{srand()} {x[NR] = $0} END{print "Selected", x[1 + int(rand() * NR)]}'
2011-03-13 20:05:06
User: saibbot
Functions: awk ls
Tags: awk random

I use this command to select a random movie from my movie collection..

env LC_CTYPE=C tr -dc "a-zA-Z0-9-_\$\?" < /dev/urandom | head -c 10
2011-02-22 17:09:44
User: aerickson
Functions: env head tr



fixes a problem with bad bytes in /dev/urandom on Mac OS X

files=(/usr/share/cowsay/cows/*); cowsay -f `echo ${files[$((RANDOM%${#files}))]}` <TEXT>
2011-02-20 05:43:01
User: lkjoel

This will show a random cow with cowsay.

perl -e 'printf "%vd\n",pack "N",rand 256**4'