| .TH "pubasync" 3 "Thu Sep 13 2018" "Paho MQTT C Client Library" \" -*- nroff -*- |
| .ad l |
| .nh |
| .SH NAME |
| pubasync \- Asynchronous publication example |
| |
| .PP |
| .nf |
| #include <stdio\&.h> |
| #include <stdlib\&.h> |
| #include <string\&.h> |
| #include "MQTTClient\&.h" |
| |
| #define ADDRESS "tcp://localhost:1883" |
| #define CLIENTID "ExampleClientPub" |
| #define TOPIC "MQTT Examples" |
| #define PAYLOAD "Hello World!" |
| #define QOS 1 |
| #define TIMEOUT 10000L |
| |
| volatile MQTTClient_deliveryToken deliveredtoken; |
| |
| void delivered(void *context, MQTTClient_deliveryToken dt) |
| { |
| printf("Message with token value %d delivery confirmed\n", dt); |
| deliveredtoken = dt; |
| } |
| |
| int msgarrvd(void *context, char *topicName, int topicLen, MQTTClient_message *message) |
| { |
| int i; |
| char* payloadptr; |
| |
| printf("Message arrived\n"); |
| printf(" topic: %s\n", topicName); |
| printf(" message: "); |
| |
| payloadptr = message->payload; |
| for(i=0; i<message->payloadlen; i++) |
| { |
| putchar(*payloadptr++); |
| } |
| putchar('\n'); |
| MQTTClient_freeMessage(&message); |
| MQTTClient_free(topicName); |
| return 1; |
| } |
| |
| void connlost(void *context, char *cause) |
| { |
| printf("\nConnection lost\n"); |
| printf(" cause: %s\n", cause); |
| } |
| |
| int main(int argc, char* argv[]) |
| { |
| MQTTClient client; |
| MQTTClient_connectOptions conn_opts = MQTTClient_connectOptions_initializer; |
| MQTTClient_message pubmsg = MQTTClient_message_initializer; |
| MQTTClient_deliveryToken token; |
| int rc; |
| |
| MQTTClient_create(&client, ADDRESS, CLIENTID, |
| MQTTCLIENT_PERSISTENCE_NONE, NULL); |
| conn_opts\&.keepAliveInterval = 20; |
| conn_opts\&.cleansession = 1; |
| |
| MQTTClient_setCallbacks(client, NULL, connlost, msgarrvd, delivered); |
| |
| if ((rc = MQTTClient_connect(client, &conn_opts)) != MQTTCLIENT_SUCCESS) |
| { |
| printf("Failed to connect, return code %d\n", rc); |
| exit(EXIT_FAILURE); |
| } |
| pubmsg\&.payload = PAYLOAD; |
| pubmsg\&.payloadlen = strlen(PAYLOAD); |
| pubmsg\&.qos = QOS; |
| pubmsg\&.retained = 0; |
| deliveredtoken = 0; |
| MQTTClient_publishMessage(client, TOPIC, &pubmsg, &token); |
| printf("Waiting for publication of %s\n" |
| "on topic %s for client with ClientID: %s\n", |
| PAYLOAD, TOPIC, CLIENTID); |
| while(deliveredtoken != token); |
| MQTTClient_disconnect(client, 10000); |
| MQTTClient_destroy(&client); |
| return rc; |
| } |
| |
| .fi |
| .PP |
| |