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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

Polls fos network port usage

Terminal - Polls fos network port usage
while sleep 1; do date; (netstat -a -n | grep 80) ; done
2011-05-16 07:56:56
User: hute37
Functions: grep netstat sleep
Polls fos network port usage


There are 5 alternatives - vote for the best!

Terminal - Alternatives
watch 'netstat -anptu |egrep "^Proto|:80 "'
2011-05-18 15:05:52
User: Mozai
Functions: egrep watch

Shows updated status in a terminal window for connections to port '80' in a human-friendly form. Use 'watch -n1' to update every second, and 'watch -d' to highlight changes between updates.

If you wish for status updates on a port other than '80', always remember to put a space afterwards so that ":80" will not match ":8080".

Know a better way?

If you can do better, submit your command here.

What others think

watch lsof -i :80

Comment by zolden 284 weeks and 3 days ago

netstat already has '-c' option for continuous (once-per-second) output. You can pipe the output to grep, no need for subshells. zolden has the right idea: for human-readable status updates, use /usr/bin/watch.

Furthermore, 'grep 80' will also match ports 8000 and 8080, process IDs 80 and 800, and any IP address with '.80' in it.

Comment by Mozai 284 weeks and 1 day ago

Your point of view

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