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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.

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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.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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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:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

remove empty lines

Terminal - remove empty lines
sed '/^$/d'
2010-04-18 00:52:00
User: er0k
Functions: sed
remove empty lines


There are 2 alternatives - vote for the best!

Terminal - Alternatives
sed -e '/^$/d' -i .bak filewithempty.lines
2011-03-24 00:03:25
User: donnoman
Functions: sed

Modify file in place to remove empty lines and create a backup of the original with the extension .bak

sed '/^$/d' /tmp/data.txt > /tmp/output.txt
grep -v '^#\|^$' /etc/hdparm.conf
2010-04-18 08:01:07
Functions: grep

Removes all empty lines: ^$

and all lines starting with hash: ^#

Know a better way?

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