// Given that we can't set KeepAliveInterval alone, and this code path
		// is new, it doesn't exist before, so we just return an error.
		return syscall.WSAENOPROTOOPT
	case idle >= 0 && interval < 0:
		// Although we can't set KeepAliveTime alone either, this existing code
		// path had been backing up [SetKeepAlivePeriod] which used to be set both
		// KeepAliveTime and KeepAliveInterval to 15 seconds.

	User                 string         `json:"username"`
	Password             string         `json:"password"`
	MaxReconnectInterval time.Duration  `json:"reconnectInterval"`
	KeepAlive            time.Duration  `json:"keepAliveInterval"`
	RootCAs              *x509.CertPool `json:"-"`
	QueueDir             string         `json:"queueDir"`
	QueueLimit           uint64         `json:"queueLimit"`
}

// Validate MQTTArgs fields