tcp_create_listener/2 creates a passive socket to listen for
If Address is unbound,
tcp_create_listener/2 establishes a
listener on a dynamic port and binds Address to
an address term of the form
tcp_create_listener/2 will establish a listener
on a fixed port if Address is bound to an address term with
Port set to the specific port number.
Note that only privileged (or
root) processes can use port numbers
less than 1024.
tcp_create_listener/2 returns immediately after creating the socket
that is used for accepting connection requests and returns the socket
identifier in PassiveSocket. Connection requests are accepted by the
select predicates (see ipc-tcp-trm-select1).