C语言中打印返回值

demo：

 ----return :返回值------------------

         int mosquitto_username_pw_set(struct mosquitto *mosq, const char *username, const char *password)
              {
                      if(!mosq) return MOSQ_ERR_INVAL;

                   if(mosq->username){
                   _mosquitto_free(mosq->username);
                  mosq->username = NULL;
                    }
                  if(mosq->password){
                 _mosquitto_free(mosq->password);
                 mosq->password = NULL;
               }

              if(username){
                   mosq->username = _mosquitto_strdup(username);
                  if(!mosq->username) return MOSQ_ERR_NOMEM;
             if(password){
                  mosq->password = _mosquitto_strdup(password);
                  if(!mosq->password){
                  _mosquitto_free(mosq->username);
                  mosq->username = NULL;
                 return MOSQ_ERR_NOMEM;
             }
         }
     }
                return MOSQ_ERR_SUCCESS;
  }

//----------------------------------------------------------------------------------------------------

    void main(void){

           int x=1;

                x= mosquitto_username_pw_set(mosq, username, password);
                printf("----------------------------------------------data= %d\n",x);
                printf("username= %s\n",username);

}

C语言中打印返回值

原文：http://www.cnblogs.com/dpf-learn/p/6963648.html