天嵌二次封装库使用手册
V2.1.2
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#include <MQTTClient.h>
Public 属性 | |
char | struct_id [4] |
int | struct_version |
const char * | topicName |
const char * | message |
int | retained |
int | qos |
struct { | |
int len | |
const void * data | |
} | payload |
MQTTClient_willOptions defines the MQTT "Last Will and Testament" (LWT) settings for the client. In the event that a client unexpectedly loses its connection to the server, the server publishes the LWT message to the LWT topic on behalf of the client. This allows other clients (subscribed to the LWT topic) to be made aware that the client has disconnected. To enable the LWT function for a specific client, a valid pointer to an MQTTClient_willOptions structure is passed in the MQTTClient_connectOptions structure used in the MQTTClient_connect() call that connects the client to the server. The pointer to MQTTClient_willOptions can be set to NULL if the LWT function is not required.
在文件 MQTTClient.h 第 611 行定义.
const void* MQTTClient_willOptions::data |
binary payload data
在文件 MQTTClient.h 第 636 行定义.
int MQTTClient_willOptions::len |
binary payload length
在文件 MQTTClient.h 第 635 行定义.
const char* MQTTClient_willOptions::message |
The LWT payload in string form.
在文件 MQTTClient.h 第 622 行定义.
struct { ... } MQTTClient_willOptions::payload |
The LWT payload in binary form. This is only checked and used if the message option is NULL
int MQTTClient_willOptions::qos |
The quality of service setting for the LWT message (see MQTTClient_message.qos and qos).
在文件 MQTTClient.h 第 631 行定义.
int MQTTClient_willOptions::retained |
The retained flag for the LWT message (see MQTTClient_message.retained).
在文件 MQTTClient.h 第 626 行定义.
char MQTTClient_willOptions::struct_id[4] |
The eyecatcher for this structure. must be MQTW.
在文件 MQTTClient.h 第 614 行定义.
int MQTTClient_willOptions::struct_version |
The version number of this structure. Must be 0 or 1 0 means there is no binary payload option
在文件 MQTTClient.h 第 618 行定义.
const char* MQTTClient_willOptions::topicName |
The LWT topic to which the LWT message will be published.
在文件 MQTTClient.h 第 620 行定义.