Question

我已经使用我的设备连接到IBM Iot Foundation，据我所知，有两种方法可以建立连接：quickstart和已注册的设备。首先，我尝试连接到快速入门。（quickstart.messaging.internetofthings.ibmcloud.com）我从paho。（http://www.eclipse.org/paho/）下载了C / C ++ MQTT嵌入式客户端库，套接字已成功建立并且代码中没有错误，我建立了mqttconnect，我无法接收响应CONNACK，它直接转到退出。什么可能导致这个问题？

len = MQTTSerialize_connect((unsigned char*)buf, buflen, &data);
rc=transport_sendPacketBuffer(mysock,buf,len);
/****wait for connack***/
if (MQTTPacket_read(buf, buflen, transport_getdata) == CONNACK)
{
    unsigned char sessionPresent, connack_rc;
    printf("receive connack\n");// can't print this setence.
    if (MQTTDeserialize_connack(&sessionPresent, &connack_rc, buf, buflen) != 1 || connack_rc != 0)
    {
        printf("Unable to connect, return code %d\n", connack_rc);
        goto exit;
    }
}
else
    goto exit;  

topicString.cstring = "iot-2/evt/status/fmt/json";
len += MQTTSerialize_publish((unsigned char *)(buf + len), buflen - len, 0, 0, 0, 0, topicString, (unsigned char *)payload, payloadlen);  
    len += MQTTSerialize_disconnect((unsigned char *)(buf + len), buflen - len);
rc=transport_sendPacketBuffer(mysock,buf,len);

if (rc == len)
    printf("Successfully published\n");
else
    printf("Publish failed\n");
exit:
   printf("close socket.\n");
   transport_close(mysock);

无法通过使用MQTT协议连接到IBM Iot基础来接收CONNACK

0 个答案: