PacketPeerUDP

Inherits: PacketPeer < Reference < Object

UDP packet peer.

Description

UDP packet peer. Can be used to send raw UDP packets as well as Variants.

Methods

Method Descriptions

• void close ( )

Closes the UDP socket the PacketPeerUDP is currently listening on.

• Error connect_to_host ( String host, int port )

Calling this method connects this UDP peer to the given host/port pair. UDP is in reality connectionless, so this option only means that incoming packets from different addresses are automatically discarded, and that outgoing packets are always sent to the connected address (future calls to set_dest_address are not allowed). This method does not send any data to the remote peer, to do that, use PacketPeer.put_var or PacketPeer.put_packet as usual. See also UDPServer.

Note: Connecting to the remote peer does not help to protect from malicious attacks like IP spoofing, etc. Think about using an encryption technique like SSL or DTLS if you feel like your application is transferring sensitive information.

• String get_packet_ip ( ) const

Returns the IP of the remote peer that sent the last packet(that was received with PacketPeer.get_packet or PacketPeer.get_var).

• int get_packet_port ( ) const

Returns the port of the remote peer that sent the last packet(that was received with PacketPeer.get_packet or PacketPeer.get_var).

• bool is_connected_to_host ( ) const

Returns true if the UDP socket is open and has been connected to a remote address. See connect_to_host.

• bool is_listening ( ) const

Returns whether this PacketPeerUDP is listening.

• Error join_multicast_group ( String multicast_address, String interface_name )

Joins the multicast group specified by multicast_address using the interface identified by interface_name.

You can join the same multicast group with multiple interfaces. Use IP.get_local_interfaces to know which are available.

Note: Some Android devices might require the CHANGE_WIFI_MULTICAST_STATE permission for multicast to work.

• Error leave_multicast_group ( String multicast_address, String interface_name )

Removes the interface identified by interface_name from the multicast group specified by multicast_address.

• Error listen ( int port, String bind_address=”*“, int recv_buf_size=65536 )

Makes this PacketPeerUDP listen on the port binding to bind_address with a buffer size recv_buf_size.

If bind_address is set to "*" (default), the peer will listen on all available addresses (both IPv4 and IPv6).

If bind_address is set to "0.0.0.0" (for IPv4) or "::" (for IPv6), the peer will listen on all available addresses matching that IP type.

If bind_address is set to any valid address (e.g. "192.168.1.101", "::1", etc), the peer will only listen on the interface with that addresses (or fail if no interface with the given address exists).

• void set_broadcast_enabled ( bool enabled )

Enable or disable sending of broadcast packets (e.g. set_dest_address("255.255.255.255", 4343). This option is disabled by default.

Note: Some Android devices might require the CHANGE_WIFI_MULTICAST_STATE permission and this option to be enabled to receive broadcast packets too.

• Error set_dest_address ( String host, int port )

Sets the destination address and port for sending packets and variables. A hostname will be resolved using DNS if needed.

Note: set_broadcast_enabled must be enabled before sending packets to a broadcast address (e.g. 255.255.255.255).

• Error wait ( )

Waits for a packet to arrive on the listening port. See listen.

Note: wait can’t be interrupted once it has been called. This can be worked around by allowing the other party to send a specific “death pill” packet like this:

# Server
socket.set_dest_address("127.0.0.1", 789)
socket.put_packet("Time to stop".to_ascii())
# Client
while socket.wait() == OK:
    var data = socket.get_packet().get_string_from_ascii()
    if data == "Time to stop":
        return