REXX and IP Sockets

Hi there

Can anyone give me an example of a rexx program
just listening on a given portnumber on the netword card
(a la wireshark)?

I have dl'ed the zip file "NetCentric Computing with Object REXX" -
and can fine make connections to ie the chat server.

But for a networking/tcp course I need to be able to listen to Upnp
protocols (and send commands).

But a short example would help me a lot

I'm on Windows with ooRexx 3.2

Best regards
Mette