func SetBpfDatalink(fd, t int) (int, error) {
	err := ioctlPtr(fd, BIOCSDLT, unsafe.Pointer(&t))
	if err != nil {
		return 0, err
	}
	return t, nil
}

// Deprecated: Use golang.org/x/net/bpf instead.
func SetBpfPromisc(fd, m int) error {
	err := ioctlPtr(fd, BIOCPROMISC, unsafe.Pointer(&m))
	if err != nil {
		return err
	}
	return nil
}

// Deprecated: Use golang.org/x/net/bpf instead.
func FlushBpf(fd int) error {