determine if tcp port is open

nc -zw2 80 && echo open
@putnamhill, no need if statement in that case. && is a AND and || is a OR

By: sputnick
2009-12-07 21:35:25

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What Others Think

@sputnick, thanks for the && tip. This came from a script of mine that includes an else clause. Does look much cleaner with the and construct.
putnamhill · 662 weeks and 1 day ago
poor man's nmap...nice!
bubo · 662 weeks ago
nc is absolutely not a poor mans nmap. If anything, nmap is a wrapper for a watered down netcat. Things netcat can do, which nmap cannot. #1 Assist in hard drive cloning across the network. #2 Be a telnet server #3 Be a chat server #4 Transfer files #5 Be a web server #6 Proxy dns requests #7 Proxy ssh requests ...
Zhoul · 511 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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