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

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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.
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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

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Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Random unsigned integer

Terminal - Random unsigned integer
echo $(openssl rand 4 | od -DAn)
2010-11-09 14:55:39
User: putnamhill
Functions: echo od
12
Random unsigned integer

Alternatives

There are 3 alternatives - vote for the best!

Terminal - Alternatives
echo $RANDOM
2010-11-09 09:57:44
User: depesz
Functions: echo
Tags: random
7

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.

od -N 4 -t uL -An /dev/random | tr -d " "
2010-11-09 07:57:16
User: hfs
Functions: od tr
Tags: random
2

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

curl -s "https://www.random.org/cgi-bin/randbyte?nbytes=4" | od -DAn
2010-11-09 18:26:24
Functions: od
Tags: random
-1

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

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