+ time_t wtime;
+ struct tm *ltime;
+ char buffer[80];
+ string year;
+ string month;
+ string date;
+
+ time(&wtime);
+ ltime = localtime(&wtime);
+ strftime(buffer, 80, "%Y", ltime);
+ year = buffer;
+ strftime(buffer, 80, "%m", ltime);
+ month = buffer;
+ strftime(buffer, 80, "%Y-%m-%d", ltime);
+ date = buffer;
+
+ struct tm * gmtime(const time_t *timer);
+ struct tm * localtime(const time_t * timer);
+ struct stat st;
+
+ file_path = location + year;
+ if (stat(file_path.c_str() ,&st) != 0) {
+ mkdir(file_path.c_str(), 0755);
+ }
+ file_path = file_path + "/" + month;
+ if (stat(file_path.c_str() ,&st) != 0) {
+ mkdir(file_path.c_str(), 0755);
+ }
+ file_path = file_path + "/" + device_id + "_" + date + ".txt";
+ ofstream data_file(file_path.c_str(), ios::app);
+ cout << "storing to " << file_path << ", data size " << string_list->size() << endl;