pub fn listen(ty: RedirType, addr: SocketAddr) -> io::Result<UdpRedirSocket> {
        UdpRedirSocket::bind(ty, addr, false)
    }
Create a new UDP socket binded to `addr`

This will allow listening to `addr` that is not in local host
crates/shadowsocks-service/src/local/redir/udprelay/sys/unix/openbsd.rs