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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

Delete the specified line

Terminal - Delete the specified line
sed -i 8d ~/.ssh/known_hosts
2009-03-03 01:13:28
User: prayer
Functions: sed
Delete the specified line


There are 2 alternatives - vote for the best!

Terminal - Alternatives
sed -i 3d ~/.ssh/known_hosts
2011-05-26 11:34:03
User: evandrix
Functions: sed

deletes line 3 in known_hosts text file

Know a better way?

If you can do better, submit your command here.

What others think

The -e option isn't needed in this example (at least not on the two different linux systems I ran it on [CentOS 5, and a very old SUSE 7]).

Comment by leper421 429 weeks and 6 days ago

meh. i meant to hit up, but my mouse moved as i clicked, and i accidentally voted it down. sorry.

i love this command. this beats hands down opening the file with vim, locating the line, and deleting it. quick, easy, painless. great command.

Comment by atoponce 429 weeks and 6 days ago

I have and old Solaris 9 and this doesn't work. Any alternate way to do the same?

uname -srmp

SunOS 5.9 sun4u sparc

sed -i

sed: illegal option -- i

Comment by Kaio 323 weeks and 4 days ago

Your point of view

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