Bidirectional with Socket PDU

This will probably show my networking ignorance, but is there a way to
use the socket PDU for bi-directional purposes? I see that it has a PDU
in and out, but I cant’ seem to get it to work.

What I am doing is connection netcat to it with the PDU in UDP Server
mode with “nc -u localhost 52001” and I can transmit to it. But I know
that I cannot open a listening port with “nc -ul localhost 52001” since
the port is bound.

Is there a way to write and listen on the same port, or am I totally
screwing how networking works (the only reason I would think there might
be a way is because the GRC script allows me to connect the PDU in and
out at the same time without throwing an error)?

You should be fine connecting both input and output ports at the same
time for exactly this purpose!