std::net::ToSocketAddrs

Trait std::net::ToSocketAddrs

pub trait ToSocketAddrs {
    type Iter: Iterator<Item = SocketAddr>;
    fn to_socket_addrs(&self) -> Result<Self::Iter>;
}

A trait for objects which can be converted or resolved to one or more SocketAddr values.

This trait is used for generic address resolution when constructing network objects. By default it is implemented for the following types:

• SocketAddr: to_socket_addrs is the identity function.

• SocketAddrV4, SocketAddrV6, (IpAddr,u16), (Ipv4Addr,u16), (Ipv6Addr,u16): to_socket_addrs constructs a SocketAddr trivially.

• (&str,u16): the string should be either a string representation of an IpAddr address as expected by FromStr implementation or a host name.

• &str: the string should be either a string representation of a SocketAddr as expected by its FromStr implementation or a string like <host_name>:<port> pair where <port> is a u16 value.

This trait allows constructing network objects like TcpStream or UdpSocket easily with values of various types for the bind/connection address. It is needed because sometimes one type is more appropriate than the other: for simple uses a string like "localhost:12345" is much nicer than manual construction of the corresponding SocketAddr, but sometimes SocketAddr value is the main source of the address, and converting it to some other type (e.g. a string) just for it to be converted back to SocketAddr in constructor methods is pointless.

Addresses returned by the operating system that are not IP addresses are silently ignored.

Examples

use std::net::{SocketAddrV4, TcpStream, UdpSocket, TcpListener, Ipv4Addr};

fn main() {
    let ip = Ipv4Addr::new(127, 0, 0, 1);
    let port = 12345;

    // The following lines are equivalent modulo possible "localhost" name
    // resolution differences
    let tcp_s = TcpStream::connect(SocketAddrV4::new(ip, port));
    let tcp_s = TcpStream::connect((ip, port));
    let tcp_s = TcpStream::connect(("127.0.0.1", port));
    let tcp_s = TcpStream::connect(("localhost", port));
    let tcp_s = TcpStream::connect("127.0.0.1:12345");
    let tcp_s = TcpStream::connect("localhost:12345");

    // TcpListener::bind(), UdpSocket::bind() and UdpSocket::send_to()
    // behave similarly
    let tcp_l = TcpListener::bind("localhost:12345");

    let mut udp_s = UdpSocket::bind(("127.0.0.1", port)).unwrap();
    udp_s.send_to(&[7], (ip, 23451)).unwrap();
}

Associated Types

Required Methods

Implementors

• impl ToSocketAddrs for SocketAddr
• impl ToSocketAddrs for SocketAddrV4
• impl ToSocketAddrs for SocketAddrV6
• impl ToSocketAddrs for (IpAddr, u16)
• impl ToSocketAddrs for (Ipv4Addr, u16)
• impl ToSocketAddrs for (Ipv6Addr, u16)
• impl<'a> ToSocketAddrs for (&'a str, u16)
• impl ToSocketAddrs for str
• impl<'a> ToSocketAddrs for &'a [SocketAddr]
• impl<'a, T: ToSocketAddrs + ?Sized> ToSocketAddrs for &'a T
• impl ToSocketAddrs for String