connect_test.c mosquitto threaded - MWE

connect_test.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <mosquitto.h>

// compile with 
// gcc -o connect_test -lmosquitto -pthread connect_test.c
// run with
// ./connect_test
struct mosquitto *global_mosq = NULL;
char* hostname = "mqtt.eclipse.org";
uint32_t port = 1883;

void _cb_log( struct mosquitto *mosq,  void *userdata, int level, const char *str) {
  printf("[MQTT_%d]: %s\n", level, str);
}

void on_disconnect( struct mosquitto *mosq, void *userdata, int rc) {
  printf("[MQTT]: disconnected\n");
}

void on_connect(struct mosquitto *mosq,  void *userdata, int rc) {
  printf("[MQTT]: connected\n");

}

void main() {
  int keepalive = 60;
  mosquitto_lib_init();
  printf("mosq_new success: %s\n",(global_mosq = mosquitto_new(NULL, true, NULL)) ? "Yes" : "No");
  mosquitto_log_callback_set(global_mosq, _cb_log);
  mosquitto_disconnect_callback_set(global_mosq, on_disconnect);
  mosquitto_connect_callback_set(global_mosq, on_connect);
  printf("connect_async returned: %d\n", mosquitto_connect_async(global_mosq, hostname, port, keepalive));
  printf("loop_start returned: %d\n",mosquitto_loop_start(global_mosq));
  //the following line works
  //mosquitto_loop_forever(global_mosq,-1,1);
  while(1){sleep(1);}
}