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Is anybody else not able to get nc -lp 8888 working on Mac OS X? Is there another way to get this to work?

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5 Answers 5

Reset to default
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It looks to me as if the -p option does nothing on the OS X version of netcat. To get it to work, I must do nc -l localhost 8888.

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    Unless installed from homebrew, then nc -l -p 8888 works.
    – user1338062
    Commented Dec 3, 2012 at 13:27
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    From man nc: -l ... It is an error to use this option in conjunction with the -p, -s, or -z options. ... You probably want to just stick with @kzh's command there
    – fatuhoku
    Commented Oct 11, 2013 at 18:41
  • @fatuhoku I just checked my manual, and yest it does say that in there, but the weird thing is that if I do nc -lp 8888 or nc -l -p 8888 it will then take -p to mean listening port. So my distributed copy does not listen to its own manual!
    – kzh
    Commented Oct 11, 2013 at 20:31
  • Agreed! Flags are a bit too expressive... it should have just refused to do any useful work, output a message and quit!
    – fatuhoku
    Commented Oct 11, 2013 at 21:02
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    Works also with nc -l 8888
    – polym
    Commented Jun 19, 2015 at 10:49
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Here's how this is working for me on OS X 10.10, with either the installed BSD version, or the one from Homebrew:

BSD Version

When using the BSD version that ships with OS X, a server can be started like this

/usr/bin/nc -l 9999

Homebrew

  • Install using Homebrew: brew install netcat
  • This will install v0.7.1 of http://netcat.sourceforge.net/
  • One can use either the nc or netcat command. nc is an alias for netcat.

To start a server:

nc -l -p 9999

To start a client:

nc targethost 9999

To get the manpage of this version, one needs to use man netcat, as man nc will open the manpage of the BSD version.

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I needed to test a web service over SSL, which ncat (made by the nmap team) supports. 

brew install nmap
ncat -C --ssl api.somecompany.com 443

https://nmap.org/ncat/

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nc on MacOS has too many bugs, and Apple did none patch for years. the netcat from homebrew is a very low version. use ncat from nmap instead

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    +1, as of today, netcat --version is 0.7.1 (2003) for brew installed netcat. Terrible.
    – ijoseph
    Commented Oct 20, 2020 at 22:29
  • Get the nmap version here (link)
    – ijoseph
    Commented Oct 20, 2020 at 22:30
  • "nc on MacOS has too many bugs" -> I can only confirm this. 😕 Fiddling around with it today and facing some inconsistent behaviours. I believe this version of nc from 2005 is the one that they're still using. Ended up using socat instead: brew install socat.
    – Glenn Mohammad
    Commented Apr 30, 2022 at 21:10
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Based on the nc manual from Mac:

NC(1) General Commands Manual NAME nc – arbitrary TCP and UDP connections and listens

-l      Used to specify that nc should listen for an incoming connection rather than initiate a connection to a remote
             host.

It is an error to use this option in conjunction with the -p, -s, or -z options. Additionally, any timeouts specified with the -w option are ignored.

Working example:

nc -lv 9001

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