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Commands tagged random

Terminal - Commands tagged random - 65 results

a=(*); echo ${a[$((RANDOM % ${#a[@]}))]}

2011-03-18 13:24:52

User: putnamhill

Functions: echo

Tags: bash random

-1

Up
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Selecting a random file/folder of a folder

Here's a bash version using an array.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

for i in *; do echo "$i"; done | shuf -n1

2011-03-17 17:48:42

User: johnraff

Functions: echo

Tags: bash random

-2

Up
Down

Selecting a random file/folder of a folder

Choose random file from current folder. Avoids using ls.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

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

-3

Up
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Play a random [album/movie] two rows down

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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

ls -1 | shuf -n 1

2011-03-13 22:14:57

User: quincymd

Functions: ls

Tags: bash random

Up
Down

Selecting a random file/folder of a folder

random file from files in directory

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo Selected $(ls -1 | sort -R | head -n 1)

2011-03-13 22:06:54

User: Juluan

Functions: echo head ls sort

Tags: sort random

-3

Up
Down

Selecting a random file/folder of a folder

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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

-3

Up
Down

Selecting a random file/folder of a folder

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.

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ls -1 | sort -R | sed -n 's/^/Selected /;1p'

2011-03-13 21:00:28

User: flatcap

Functions: ls sed sort

Tags: sort sed random

-5

Up
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Selecting a random file/folder of a folder

Select a file/folder at random.

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

-3

Up
Down

Selecting a random file/folder of a folder

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

Tags: password random generate mac os x

Up
Down

generate random password (works on Mac OS X)

Prepending

env LC_CTYPE=C

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

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files=(/usr/share/cowsay/cows/*); cowsay -f `echo ${files[$((RANDOM%${#files}))]}` <TEXT>

2011-02-20 05:43:01

User: lkjoel

Tags: random cowsay cowfile

-4

Up
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Cowsay Random Cowfile

This will show a random cow with cowsay.

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

2011-01-18 06:10:18

User: seungwon

Functions: perl

Tags: random

-1

Up
Down

Perl One Liner to Generate a Random IP Address

echo $((RANDOM%256)).$((RANDOM%256)).$((RANDOM%256)).$((RANDOM%256))

2011-01-16 23:02:01

User: putnamhill

Functions: echo

Tags: bash random

Up
Down

Perl One Liner to Generate a Random IP Address

A bash version.

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seq -w 50 | sort -R | head -6 |fmt|tr " " "-"

2011-01-05 01:12:58

User: metalx1000

Functions: head seq sort tr

Tags: random range shuf

Up
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lotto generator

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shuf -i 1-49 -n 6 | sort -n | xargs

2011-01-05 00:07:46

User: niall

Functions: sort

Tags: random range shuf

Up
Down

lotto generator

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cat /dev/urandom | hexdump -C | highlight ca fe 3d 42 e1 b3 ae f8 | perl -MTime::HiRes -pne "Time::HiRes::usleep(rand()*1000000)"

2010-12-29 21:26:18

User: doherty

Functions: cat hexdump perl

Tags: bash perl hexdump random highlight

Up
Down

shell equivalent of a boss button

Nobody wants the boss to notice when you're slacking off. This will fill your shell with random data, parts of it highlighted. Note that 'highlight' is the Perl module App::highlight, not "a universal sourcecode to formatted text converter." You'll also need Term::ANSIColor.

curl -s "https://www.random.org/cgi-bin/randbyte?nbytes=4" | od -DAn

2010-11-09 18:26:24

User: PhillipNordwall

Functions: od

Tags: random

-1

Up
Down

Random unsigned integer

Grab 4 bytes from www.random.org over ssl and format them as an integer

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo $(openssl rand 4 | od -DAn)

2010-11-09 14:55:39

User: putnamhill

Functions: echo od

Tags: openssl random

Up
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Random unsigned integer

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echo $RANDOM

2010-11-09 09:57:44

User: depesz

Functions: echo

Tags: random

Up
Down

Random unsigned integer

works at least in bash. returns integer in range 0-32767. range is not as good, but for lots of cases it's good enough.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

od -N 4 -t uL -An /dev/random | tr -d " "

2010-11-09 07:57:16

User: hfs

Functions: od tr

Tags: random

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Random unsigned integer

Reads 4 bytes from the random device and formats them as unsigned integer between 0 and 2^32-1.

dd if=/dev/urandom of=/dev/dsp

2010-10-27 09:25:02

User: khashmeshab

Functions: dd

Tags: speaker beep sound random

-5

Up
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Random Beeps on Your Audio Card's Output

Sends random sounds to your sound card output (e.g. your speaker). Think... You can also run it remotely on another computer using SSH and scare its user!

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

dd if=/dev/urandom of=/dev/speaker bs=1

2010-10-27 09:22:40

User: khashmeshab

Functions: dd

Tags: speaker beep random

-5

Up
Down

Random Beeps on Your PC Speaker

Sends random beeps to your PC-speaker. Think... You can also run it remotely on another computer using SSH and scare its user! Don't forget to run it on your dedicated hosting server and watch sysadmin's action from data-center's live remote cameras!

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cycle(){ while :;do((i++));echo -n "${3:$(($i%${#3})):1}";sleep .$(($RANDOM%$2+$1));done;}

2010-10-08 23:45:40

User: putnamhill

Functions: echo sleep

Tags: sleep random

Up
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continuously print string as if being entered from the keyboard

Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption.

cycle 1 3 $(openssl rand 100 | xxd -p)

Fans of "The Shining" might get a kick out of this:

cycle 1 4 ' All work and no play makes Jack a dull boy.'

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sort -R SOMEFILE

2010-09-16 22:29:27

User: miniker84

Functions: sort

Tags: sort sorting random shuf

Up
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Randomize lines in a file

Works in sort (GNU coreutils) 7.4, don't know when it was implemented but sometime the last 6 years.

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shuf SOMEFILE

2010-09-16 12:45:28

User: dooblem

Tags: random shuf

Up
Down

Randomize lines in a file

shuf is in the coreutils package

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feh --bg-center `ls | shuf -n 1`

2010-09-06 14:15:08

User: uzsolt

Tags: random

-2

Up
Down

Set background image to random file from current dir.

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