}
	return
}

// Sendmsg sends a message on a socket to an address using the sendmsg system
// call. This function is equivalent to SendmsgN, but does not return the
// number of bytes actually sent.
func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
	_, err = SendmsgN(fd, p, oob, to, flags)
	return
}

// SendmsgN sends a message on a socket to an address using the sendmsg system

	if rsa.Addr.Family != AF_UNSPEC {
		from, err = anyToSockaddr(&rsa)
	}
	return
}

func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
	_, err = SendmsgN(fd, p, oob, to, flags)
	return
}

func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
	var ptr unsafe.Pointer
	var salen _Socklen
	if to != nil {

func Sendto(fd int, p []byte, flags int, to Sockaddr) error {
	return ENOSYS
}

func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn, recvflags int, from Sockaddr, err error) {
	return 0, 0, 0, nil, ENOSYS
}

func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
	return 0, ENOSYS
}

func GetsockoptInt(fd, level, opt int) (value int, err error) {
	return 0, ENOSYS
}

func Sendto(fd int, p []byte, flags int, to Sockaddr) error {
	return ENOSYS
}

func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn, recvflags int, from Sockaddr, err error) {
	return 0, 0, 0, nil, ENOSYS
}

func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
	return 0, ENOSYS
}

func GetsockoptInt(fd, level, opt int) (value int, err error) {
	return 0, ENOSYS
}

pkg syscall (darwin-386), func Mprotect([]uint8, int) error
pkg syscall (darwin-386), func Munlock([]uint8) error
pkg syscall (darwin-386), func Munlockall() error
pkg syscall (darwin-386), func SendmsgN(int, []uint8, []uint8, Sockaddr, int) (int, error)
pkg syscall (darwin-386-cgo), func FcntlFlock(uintptr, int, *Flock_t) error
pkg syscall (darwin-386-cgo), func Mlock([]uint8) error

	msg.Iovlen = 1
	if n, err = recvmsg(fd, &msg, flags); err != nil {
		return
	}
	oobn = int(msg.Controllen)
	recvflags = int(msg.Flags)
	return
}

//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)

func sendmsgN(fd int, p, oob []byte, ptr unsafe.Pointer, salen _Socklen, flags int) (n int, err error) {
	var msg Msghdr
	msg.Name = (*byte)(ptr)
	msg.Namelen = uint32(salen)
	var iov Iovec

	}
	if n, err = recvmsg(fd, &msg, flags); err != nil {
		return
	}
	oobn = int(msg.Controllen)
	recvflags = int(msg.Flags)
	return
}

//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)

func sendmsgN(fd int, iov []Iovec, oob []byte, ptr unsafe.Pointer, salen _Socklen, flags int) (n int, err error) {
	var msg Msghdr
	msg.Name = (*byte)(unsafe.Pointer(ptr))
	msg.Namelen = uint32(salen)

// In order to use msghdr structure with Control, Controllen, nrecvmsg and nsendmsg must be used.
//sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error) = nrecvmsg
//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error) = nsendmsg

//sys	munmap(addr uintptr, length uintptr) (err error)
//sys	Madvise(b []byte, advice int) (err error)

//sys	Shutdown(s int, how int) (err error)

// In order to use msghdr structure with Control, Controllen in golang.org/x/net,
// nrecvmsg and nsendmsg must be used.
//sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error) = nrecvmsg
//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error) = nsendmsg

func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {
	if sa.Port < 0 || sa.Port > 0xFFFF {
		return nil, 0, EINVAL

	msg.Iov = &iov
	msg.Iovlen = 1
	if n, err = recvmsg(fd, &msg, flags); err != nil {
		return
	}
	oobn = int(msg.Accrightslen)
	return
}

//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error) = libsocket.__xnet_sendmsg

func sendmsgN(fd int, p, oob []byte, ptr unsafe.Pointer, salen _Socklen, flags int) (n int, err error) {
	var msg Msghdr
	msg.Name = (*byte)(unsafe.Pointer(ptr))
	msg.Namelen = uint32(salen)