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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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Universal configuration monitoring and system of record for IT.
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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:

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

Commands by guedesav from sorted by
Terminal - Commands by guedesav - 1 results
dd if=/dev/zero of=junk bs=1M count=1K
2009-11-01 23:45:51
User: guedesav
Functions: dd
Tags: dd ram rm
-11

This is an useful command for when your OS is reporting less free RAM than it actually has. In case terminated processes did not free their variables correctly, the previously allocated RAM might make a bit sluggis over time.

This command then creates a huge file made out of zeroes and then removes it, thus freeing the amount of memory occupied by the file in the RAM.

In this example, the sequence will free up to 1GB(1M * 1K) of unused RAM. This will not free memory which is genuinely being used by active processes.