update mqttd main.c, add mosquitto publisher and subscriber

guowenxue

2019-06-25 02294c1c430ab80bd4543af28f867c5c2927e5c1

 apue/2.Socket/socket_client.c

@@ -109,7 +109,8 @@
          }
       }

       //printf("Read %d bytes data from server: '%s'\n", rv, buf);

       sleep(5);
    }