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    use crate::sys::unix::net::{new_ip_socket, socket_addr};

    use std::io;
    use std::mem;
    use std::net::{self, SocketAddr};
    use std::os::unix::io::{AsRawFd, FromRawFd};

    pub fn bind(addr: SocketAddr) -> io::Result<net::UdpSocket> {
        // Gives a warning for non Apple platforms.
        #[allow(clippy::let_and_return)]
        let socket = new_ip_socket(addr, libc::SOCK_DGRAM);

        socket.and_then(|socket| {
            let (raw_addr, raw_addr_length) = socket_addr(&addr);
            syscall!(bind(socket, raw_addr.as_ptr(), raw_addr_length))
                .map_err(|err| {
                    // Close the socket if we hit an error, ignoring the error
                    // from closing since we can't pass back two errors.
                    let _ = unsafe { libc::close(socket) };
                    err
                })
                .map(|_| unsafe { net::UdpSocket::from_raw_fd(socket) })
        })
    }

    pub(crate) fn only_v6(socket: &net::UdpSocket) -> io::Result<bool> {
        let mut optval: libc::c_int = 0;
        let mut optlen = mem::size_of::<libc::c_int>() as libc::socklen_t;

        syscall!(getsockopt(
            socket.as_raw_fd(),
            libc::IPPROTO_IPV6,
            libc::IPV6_V6ONLY,
            &mut optval as *mut _ as *mut _,
            &mut optlen,
        ))?;

        Ok(optval != 0)
    }