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.

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

Universal configuration monitoring and system of record for IT.
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

May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!
Hide

Top Tags

Hide

Functions

Hide

Credits

Commands tagged base64 from sorted by
Terminal - Commands tagged base64 - 7 results
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)

read -s pass; echo $pass | md5sum | base64 | cut -c -16
2011-11-24 20:23:47
User: bugmenot
Functions: cut echo md5sum read
22

Why remember? Generate!

Up to 48 chars, works on any unix-like system (NB: BSD use md5 instead of md5sum)

str=password; for i in `seq 1 10`; do echo -e "$str\n"; str="$(base64 <<< $str)"; done
2011-10-04 18:01:54
User: n3wborn
Functions: echo
Tags: base64
1

Just for fun, I searched a simple way to encrypt some text.

Simple base64 encoding seemed a good start so I decided to "amplify" encoding using repeted base64 encoding.

Of course, this is not really secure but can be useful to hide datas to most part of humans ;).

Do not hesitate to provide better solutions or else.

alias Z=base64&&Z=dG91Y2ggUExFQVNFX1NUT1BfQU5OT1lJTkdfQ09NTUFORExJTkVGVV9VU0VSUwo=&&$(echo $Z|Z -d)
2010-12-24 14:29:19
User: rodolfoap
Functions: alias echo
Tags: touch base64
7

Would create a file with a meaningful title. Dedicated to John Cons, who is annoying us users. Merry Christmas!!!

openssl base64 -in base64.decoded.txt -out base64.encoded.txt
2010-08-13 20:39:10
User: argherna
3

I have a mac, and do not want to install mac ports to get the base64 binary. Using openssl will do the trick just fine. Note, to decode base64, specify a '-d' after 'base64' in the command. Note also the files base64.decoded.txt and base64.encoded.txt are text files.

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
1

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()