#include <mysql.h>
#include <iostream>

MYSQL     *connection;
MYSQL_RES *queryresult[3]; // SP should return 3 resultsets
char      query[100];
int       retval;

int main()
{
   connection = mysql_init(NULL);
   if (connection == NULL)
   {
      std::cout << "Failed to get connection handler\n";
      exit(1);
   }
   mysql_real_connect(connection, 
                      "localhost",  //hostname
                      "root",       //username
                      NULL,         //password
                      "world",      //database
                      0,            //port
                      NULL,         //socket name
                      CLIENT_MULTI_STATEMENTS); // Auto sets multi_results
   if (connection == NULL)
   {
      std::cout << "Failed to connect to DB\n";
   }
   else
   {

// Using 'query' as set up in Version 2 below works, Version 1 with
// the stored procedure 1 does not, the do-while loop fails to terminate
// resulting in a Segmentation fault

// Version 1 - Call a stored procedure
      sprintf(query, "call getColour()");

// Version 2 - The stored procedure SQL reproduced
  //    sprintf(query, "select * from Coins; \
  //                    select * from Coins where Value > 20;\
  //                    select 0");

      retval = mysql_real_query(connection, query, strlen(query));
      if (retval != 0)
      {
         std::cout << "Error calling stored procedure\n";
         std::cout << mysql_error(connection) << "\n";
      }
      else
      {
         std::cout << "Stored Procedure called successfully\n"; 
         int i = 0;
         do
         {
            queryresult[i] = mysql_use_result(connection);
            if (queryresult[i] == NULL)
            {
               std::cout << "Null resultset\n";
            }
            else
            {
               std::cout << "Result set " << i << " read\n";
               mysql_free_result(queryresult[i]);
               i++;
            }
         } while(!mysql_next_result(connection));
         std::cout << "Retval=" << retval << ", resultsets= " << i << "\n";
         if (retval < 0)
         {
            std::cout << "Error occured while retrieving resultsets\n";
         }
      }
   }
   mysql_close(connection);
}