Passing MYSQL results

[DMAN3021]

I'm working on a C program that uses MYSQL to access and modify a database. Right now, I am trying to run a SELECT query on the database, and to populate a list with the results.

The thing is, in all the examples I can find, the MYSQL_RES structure is processed locally. I on the other hand, want an outside function to call my run_query() function, and then process the result set itself.

The problem I get is that the MYSQL_RES I receive from my query function is not good. Even when I debug, I can see that I have a correct result set, up until I exit my query function and return to my list function.

Anyone have an example of how to correctly pass a MYSQL_RES structure from one function to another?

Heres my code:

in connect.c

/* Run a query */
int run_query(char *query, MYSQL_RES *res_set) {
  
	if (open_connection() != 1) {
		/* could not connect to MySQL */
		print_error(&connection, "Unable to connect to MySQL");
		return 0;
		
	} else {
		if (mysql_query(&connection, query) != 0) {
			/* Query has failed */
			print_error(&connection, "Query FAILED!\n");
			close_connection();
			return 0;
			
		} else {
			/* Query has passed, process results */
			res_set = mysql_store_result(&connection);
			
			if (res_set) {
				/* If a result set was returned */
				process_result_set(res_set);
				mysql_free_result(res_set);
			} else {
				/* No result was returned */
				if (mysql_field_count(&connection) == 0) {
					printf("%lu rows affected\n", (unsigned long) mysql_affected_rows(&connection));				
				} else { /* an error occured */
					print_error(&connection, "Could not retrieve the result set");
				}
			}
		}
		
		close_connection();
	}	
	return 1;
}

in list.c

int
ListTGs( )

	{
	MYSQL_RES *res_set;
	MYSQL_ROW	row;
	MYSQL_FIELD	*field;
	char *query = "SELECT * FROM THETABLE";
	int i;

	/* Get the list */
	run_query_result(query, res_set);
	
	/*Lets try some stuff with res_set */
	mysql_field_seek(&res_set, 0);
	for (i=0; i<mysql_num_fields(&res_set); i++) {
		field = mysql_fetch_field(&res_set);
		if (row[i] == NULL) {
			printf("NULL\t");
		} else {
			printf("%s\t", row[i]);
		}
	}
	
	return( Pt_CONTINUE );
}