1. mosquitto_message_callback_set 函数的作用 mosquitto_message_callback_set 是Mosquitto MQTT C 库中的一个函数,用于设置消息回调函数。当 MQTT 客户端接收到订阅主题的消息时,Mosquitto 库会调用这个回调函数来处理接收到的消息。 函数原型如下: c int mosquitto_message_callback_set(struct mosquitto *mosq,...
voidmosquitto_message_callback_set(structmosquitto*mosq,void(*on_message)(structmosquitto*,void*,conststructmosquitto_message*))功能:消息回调函数,收到订阅的消息后调用。 参数:structmosquitto*mosq:客户端(*on_message):voidcallback(structmosquitto*mosq,void*obj,conststructmosquitto_message*message) 回调的...
mosquitto_log_callback_set(mosq, mqtt_log_callback); mosquitto_connect_callback_set(mosq, mqtt_connect_callback); mosquitto_message_callback_set(mosq, mqtt_message_callback); mosquitto_subscribe_callback_set(mosq, mqtt_subscribe_callback); //客户端连接服务器 err =mosquitto_connect(mosq, HOST...
*/ mosquitto_connect_callback_set(mosq, on_connect); mosquitto_subscribe_callback_set(mosq, on_subscribe); mosquitto_message_callback_set(mosq, on_message); /* Connect to test.mosquitto.org on port 1883, with a keepalive of 60 seconds. * This call makes the socket connection only, it ...
mosq) { std::cerr << "Failed to create MQTT client" << std::endl; return -1; } // 设置消息回调函数 mosquitto_message_callback_set(mosq, message_callback); // 连接到MQTT代理 if (mosquitto_connect(mosq, host, port, keepalive) != MOSQ_ERR_SUCCESS) { std::cerr << "MQTT ...
(4)mosquitto_message_callback_set (5)mosquitto_subscribe_callback_set (6)mosquitto_unsubscribe_callback_set (7)mosquitto_log_callback_set 八、实用功能 mosquitto_strerror 九、常见返回值 一、初始化和清理 (1)mosquitto_lib_init intmosquitto_lib_init(NULL) ...
mosquitto_message_callback_set(mosq, mqtt_message_callback); mosquitto_subscribe_callback_set(mosq, mqtt_subscribe_callback); //客户端连接服务器 err = mosquitto_connect(mosq, HOST, PORT, KEEP_ALIVE); if (err < 0){ printf("connect fail"); ...
mosquitto_connect_callback_set(mosq, on_connect); ``` 这段代码中,我们定义了一个on_connect函数作为连接回调函数。在连接成功时,会输出"Connected to broker",在连接失败时,会输出"Connection failed: rc",其中rc为具体的错误代码。然后,我们使用mosquitto_connect_callback_set函数将这个函数设置为连接回调函数...
\n"); return 1; } // 配置回调函数 mosquitto_connect_callback_set(mosq, on_connect); mosquitto_subscribe_callback_set(mosq, on_subscribe); mosquitto_message_callback_set(mosq, on_message); mosquitto_disconnect_callback_set(mosq, on_disconnect); // 连接服务器 mosquitto_username_pw_set(...
struct mosquitto *mosq(客户端)、const char*host(服务器ip地址)、int port(服务端口号)、int keepalive(保持连接的时间间隔,单位秒)当收到了订阅的消息之后,那么由 void mosquitto_message_callback_set 这个函数来实现对消息内容的处理,那么它的这个消息就是 mosquitto message *message ,后面会有一个结构体,...