// Grab both 1.6.x and 1.4.x-style locks; we don't know what the
	// iptables-restore version is if it doesn't support --wait, so we
	// can't assume which lock method it'll use.

	// Roughly duplicate iptables 1.6.x xtables_lock() function.
	l.lock16, err = os.OpenFile(lockfilePath16x, os.O_CREATE, 0600)
	if err != nil {
		return nil, fmt.Errorf("failed to open iptables lock %s: %v", lockfilePath16x, err)
	}