func setDefaultListenerSockopts(s int) error {
	// Allow reuse of recently-used addresses.
	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1))
}

func setDefaultMulticastSockopts(s int) error {
	// Allow multicast UDP and raw IP datagram sockets to listen
	// concurrently across multiple listeners.

package net

import "syscall"

func setDefaultSockopts(s, family, sotype int, ipv6only bool) error {
	return nil
}

func setDefaultListenerSockopts(s int) error {
	return nil
}

func setDefaultMulticastSockopts(s int) error {
	return nil
}

func setReadBuffer(fd *netFD, bytes int) error {
	if fd.fakeNetFD != nil {
		return fd.fakeNetFD.setReadBuffer(bytes)
	}
	return syscall.ENOPROTOOPT
}

	// This could lead to a non-deterministic behavior, where
	// connection requests over the port cannot be guaranteed
	// to be handled by the correct socket.
	return nil
}

func setDefaultMulticastSockopts(s syscall.Handle) error {
	// Allow multicast UDP and raw IP datagram sockets to listen
	// concurrently across multiple listeners.

func setDefaultListenerSockopts(s int) error {
	// Allow reuse of recently-used addresses.
	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1))
}

func setDefaultMulticastSockopts(s int) error {
	// Allow multicast UDP and raw IP datagram sockets to listen
	// concurrently across multiple listeners.

func setDefaultListenerSockopts(s int) error {
	// Allow reuse of recently-used addresses.
	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1))
}

func setDefaultMulticastSockopts(s int) error {
	// Allow multicast UDP and raw IP datagram sockets to listen
	// concurrently across multiple listeners.
	if err := syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1); err != nil {

func setDefaultListenerSockopts(s int) error {
	// Allow reuse of recently-used addresses.
	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1))
}

func setDefaultMulticastSockopts(s int) error {
	// Allow multicast UDP and raw IP datagram sockets to listen
	// concurrently across multiple listeners.
	if err := syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1); err != nil {

		// join multiple different group addresses, for
		// multiple UDP listeners that listen on the same UDP
		// port to join the same group address.
		if addr.IP != nil && addr.IP.IsMulticast() {
			if err := setDefaultMulticastSockopts(fd.pfd.Sysfd); err != nil {
				return err
			}
			addr := *addr
			switch fd.family {
			case syscall.AF_INET:
				addr.IP = IPv4zero
			case syscall.AF_INET6:
				addr.IP = IPv6unspecified