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port number

A number from 0 to 65535 that picks which program on a machine gets a network message.

A port distinguishes services on one host; an (IP address, port) pair is a SocketAddr. Binding port 0 asks the OS to choose a free one.

Examples

  • TcpListener::bind("127.0.0.1:0") asks the OS for any free port; binding a port that is already taken fails with ErrorKind::AddrInUse.

  • In "192.168.1.20:8080".parse::<SocketAddr>(), .ip() is 192.168.1.20 and .port() is 8080.

See also

IP address TCP UDP
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