Analyse TCP/UDP traffic with netcat
Sometimes you want to see what data you get through a TCP or UDP connection.
For example, you want to know how a HTTP Request look like.
It's very easy with netcat Show archive.org snapshot .
Example to listen on port 80 and the output gets to stdout.
sudo nc -kl 80
It's also possible write it into a file:
sudo nc -kl 80 > output.txt
If you use Ports higher than 1000 you don't need to be root (sudo).
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