Netcat: using nc -l port_number instead of nc -l -p port_number

Question

This question is following this one: Sockets working in openSUSE do not work in Debian?

When working with sockets on my Debian system, I have to use nc -l -p port_nu

Answer 1

I agree with duskwuff that it is better to just use the -p option everywhere, but to answer your question:

The one thing you have to do is install a netcat that supports the syntax you want. I know the netcat-openbsd package supports it. I know the netcat-traditional package does not. There's also a netcat6 package, which also doesn't. You can then explicitly request the OpenBSD version of netcat like so:

nc.openbsd -l 4242

Optionally you may use the alternatives system to set this version of netcat to run when you issue the nc command:

update-alternatives --set nc /bin/nc.openbsd

This will be done automatically for you if this is the only netcat you've installed.

Finally, you may, again optionally, remove the netcat you don't like (netcat-traditional or netcat6).