Send a UDP message. Data is a string, atom or code-list providing
the data. To is an address of the form Host:Port where Host is
either the hostname or an IP address. Defined Options are:
- encoding(+Encoding)
- Specifies the encoding to use for the string. See
udp_receive/4 for details
- as(+Type)
- This uses the same values for Type as the
as(Type) option of
udp_receive/4. The are interpreted differently though. No Type
corresponds to CVT_ALL of PL_get_chars(). Using atom
corresponds to CVT_ATOM and any of string or codes is mapped
to CVT_STRING|CVT_LIST, allowing for a SWI-Prolog string
object, list of character codes or list of characters.
Finally, term maps to CVT_WRITE_CANONICAL. This implies that
arbitrary Prolog terms can be sent reliably using the option
list `[as(term),encoding(utf8)])`, using the same option list
for udp_receive/4.
For example
send(Host, Port, Message) :-
udp_socket(S),
udp_send(S, Message, Host:Port, []),
tcp_close_socket(S).
A broadcast is achieved by using tcp_setopt(Socket, broadcast)
prior to sending the datagram and using the local network
broadcast address as a ip/4 term.
