MQTT_SUB_OPT_NO_LOCAL = 0x04 MQTT_SUB_OPT_RETAIN_AS_PUBLISHED = 0x08 MQTT_SUB_OPT_SEND_RETAIN_ALWAYS = 0x00 MQTT_SUB_OPT_SEND_RETAIN_NEW = 0x10 MQTT_SUB_OPT_SEND_RETAIN_NEVER = 0x20
