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

Make a statistic about the lines of code

Terminal - Make a statistic about the lines of code
find . -type f -name '*.c' -exec wc -l {} \; | awk '{sum+=$1} END {print sum}'
2009-09-04 15:51:30
User: arcege
Functions: awk find wc
-1
Make a statistic about the lines of code

Have wc work on each file then add up the total with awk; get a 43% speed increase on RHEL over using "-exec cat|wc -l" and a 67% increase on my Ubuntu laptop (this is with 10MB of data in 767 files).

Alternatives

There are 3 alternatives - vote for the best!

Terminal - Alternatives
find . -type f -name "*.c" -exec cat {} \; | wc -l
2009-07-30 10:06:51
User: foremire
Functions: cat find wc
1

use find to grep all .c files from the target directory, cat them into one stream, then piped to wc to count the lines

find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'
2009-09-08 08:25:45
User: karpoke
Functions: awk find tail wc xargs
Tags: awk find wc
0

This is really fast :)

time find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'

204753

real 0m0.191s

user 0m0.068s

sys 0m0.116s

Know a better way?

If you can do better, submit your command here.

What others think

wc can take multiple files as arguments, so you REALLY want to replace \; with +, enabling the "xargs mode" of the -exec option:

find . -type f -name "*.c" -exec wc -l {} + | awk '{t+=$1} END {print t}'
Comment by bwoodacre 298 weeks and 4 days ago

The "+" option is not a standard feature of find. Not all versions of Linux will support it, let alone the different flavors of UNIX out there.

Comment by arcege 298 weeks and 4 days ago

That's too bad since I find + so useful and have recommended it to so many on commandlinefu! Although for really kinky things you want xargs which more systems have, so I can see why "feature duplication" is avoided by some.

I tested it on Redhat, Ubuntu, and Debian and it works there. What non-dead UNIXes do not support the feature? I haven't been very successful at googling.

Comment by bwoodacre 298 weeks ago

Your point of view

You must be signed in to comment.