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.

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.

UpGuard checks and validates configurations for every major OS, network device, and cloud provider.

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:



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!

Top Tags



The 1 millionth fibonacci number

Terminal - The 1 millionth fibonacci number
gcc -x c -o /tmp/out - -lgmp <<< '#include <stdlib.h> ... SEE SAMPLE OUTPUT FOR FULL COMMAND
2009-09-10 02:10:46
User: hank
Functions: c++ gcc
The 1 millionth fibonacci number

It's hard to beat C. This is just slightly faster than the bc version on my machine.

real 0m26.856s

user 0m25.030s

sys 0m0.024s

Requirements: libgmp headers, gcc.


There is 1 alternative - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

Sorry Hank, you're 2 secs slower than the bc version on an atom 1.6Ghzs netbook. :)

Nice try though.

For the cash prize you need to use commonly available shell tools rather than custom c code (After all, I could probably install mathematica and beat bc!)

Comment by Escher 444 weeks and 5 days ago

Also, ~12 secs slower than bc version on a Core 2 Duo (48 secs v 36 secs)

Comment by Escher 444 weeks and 5 days ago

I voted this down because we're really stretching the limits of what is "command line fu" here. A few more like this and this place loses its charm.

I wish people would try and stick to simlpe, short-ish, command lines. Even if the utility used is not a standard or default one (exiftool in one of the other recent posts, for instance), the *command* should be one you wouldn't mind typing or pasting if needed

Comment by sitaram 444 weeks and 2 days ago

Your point of view

You must be signed in to comment.