Hide

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

OpenID
or
Sign in Register

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Hide

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

Hide

News

2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.
Hide

Tags

Hide

Functions

Hide

Credits

Site by David Winterbottom (user root).

Commands tagged random

Commands tagged random from sorted by
Terminal - Commands tagged random - 63 results
wget -qO - www.commandlinefu.com/commands/random | grep "<div class=\"command\">" | sed 's/<[^>]*>//g; s/^[ \t]*//; s/&quot;/"/g; s/&lt;/</g; s/&gt;/>/g; s/&amp;/\&/g'
2010-08-12 23:58:24
User: smop
Functions: grep sed wget
Tags: random
1
Up
Down
command line fu roulette

retrieves the html from a random command line fu page, then finds commands on the page and prints them

alternatively, pipe to bash (add "| bash" to the end) to execute the command (very risky)

edit: had to adjust to properly display the portion that replaces HTML characters (e.g. &quot; -> ")

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "$(od -An -N4 -tu4 /dev/urandom) % 5 + 1" | bc
2010-08-10 12:10:21
User: dooblem
Functions: echo
Tags: random number integer
-4
Up
Down
Random Number Between 1 And X

This is /bin/sh compatible.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
awk 'BEGIN { srand(); print rand() }'
2010-08-07 14:33:12
User: dennisw
Functions: awk
Tags: random number
-3
Up
Down
Random Decimal in the interval 0 ≤ n < 1 and 2d6 dice roll

2d6 dice:

awk 'BEGIN { srand(); a=int(rand()*6)+1; b=int(rand()*6)+1; print a " + " b " = " a+b }'

3 + 6 = 9

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo $[RANDOM%X+1]
2010-08-07 02:43:46
User: goodevilgenius
Functions: echo
Tags: random number integer
23
Up
Down
Random Number Between 1 And X

If X is 5, it will about a number between 1 and 5 inclusive.

This works in bash and zsh.

If you want between 0 and 4, remove the +1.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
fortune | cowsay -f $(ls /usr/share/cowsay/cows/ | shuf -n1)
2010-07-08 02:57:52
User: zed
Functions: ls
Tags: fortune random cowsay bashrc
6
Up
Down
Have a random "cow" say a random thing

You need to have fortune and cowsay installed. It uses a subshell to list cow files in you cow directory (this folder is default for debian based systems, others might use another folder).

you can add it to your .bashrc file to have it great you with something interesting every time you start a new session.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
perl -MDigest::SHA -e 'print substr( Digest::SHA::sha256_base64( time() ), 0, $ARGV[0] ) . "\n"' <length>
2010-04-30 21:45:46
User: udog
Functions: perl
Tags: perl password random base64 sha256
1
Up
Down
Produce a pseudo random password with given length in base 64

Of course you will have to install Digest::SHA and perl before this will work :)

Maximum length is 43 for SHA256. If you need more, use SHA512 or the hexadecimal form: sha256_hex()

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
head -c10 <(echo $RANDOM$RANDOM$RANDOM)
2009-10-09 15:09:02
User: jgc
Functions: echo head
Tags: HEAD random
0
Up
Down
Outputs a 10-digit random number

Makes use of $RANDOM environment variable.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "Decode this"| tr [a-zA-Z] $(echo {a..z} {A..Z}|grep -o .|sort -R|tr -d "\n ")
2009-09-18 06:38:28
User: dennisw
Functions: echo grep sort tr
Tags: random decode cipher
0
Up
Down
Substitution cipher

This is just for fun.

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
jot -s '' -r -n 8 0 9
2009-08-24 13:35:20
User: Hal_Pomeranz
Tags: random jot rs
1
Up
Down
Print a random 8 digit number

Don't need to pipe the output into rs if you just tell jot to use a null separator character.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
jot -r -n 8 0 9 | rs -g 0
2009-08-22 19:31:17
User: curiousstranger
Tags: random jot rs
4
Up
Down
Print a random 8 digit number
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo $(( $RANDOM % 10 + 1 ))
2009-08-22 08:57:01
User: hemanth
Functions: echo
Tags: random
3
Up
Down
Random number generation within a range N, here N=10
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
randpw(){ < /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c${1:-16};echo;}
2009-08-07 07:30:57
User: frozenfire
Functions: head tr
Tags: password random
3
Up
Down
Generate random password

Generates password consisting of alphanumeric characters, defaults to 16 characters unless argument given.

Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
awk 'BEGIN{srand()}{print rand(),$0}' SOMEFILE | sort -n | cut -d ' ' -f2-
2009-05-29 01:20:50
User: axelabs
Functions: awk cut sort
Tags: sort awk random
4
Up
Down
Randomize lines in a file

This appends a random number as a first filed of all lines in SOMEFILE then sorts by the first column and finally cuts of the random numbers.

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate