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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

list all opened ports on host

Terminal - list all opened ports on host
nmap -p 1-65535 --open localhost
2009-12-10 20:03:37
list all opened ports on host


There are 4 alternatives - vote for the best!

Terminal - Alternatives
netstat -plnt
2011-09-30 19:56:32
User: DopeGhoti
Functions: netstat

While `lsof` will work, why not use the tool designed explicitly for this job?

(If not run as root, you will only see the names of PID you own)

sudo lsof -P -i -n -sTCP:LISTEN
netstat -nptl
2009-12-11 10:23:43
User: sputnick
Functions: netstat

Alternative of OJM snippet :

This one show the IP too, where ports bind. It's very important, because if there's only instead of, connections from internet are rejected.

time { i=0; while [ $(( i < 65535 )) -eq 1 ] ; do nc -zw2 localhost $((++i)) && echo port $i opened ; done; }
2009-12-09 17:33:47
User: glaudiston
Functions: echo time

in loop, until the last port (65535), list all opened ports on host.

in the sample I used localhost, but you can replace with any host to test.

Know a better way?

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