Before you call the function, you must supply the integers to be multiplied. For the sake of simplicity, the following code sets them directly in the PBCallInfo structure.
// Set IN arguments. The prototype of the function is // integer f_mult(integer arg1, integer arg2) ci.pArgs-> GetAt(0)->SetInt(123); ci.pArgs-> GetAt(1)->SetInt(45);
Finally call the function, wrapping it in a try-catch statement to handle any runtime errors:
   // Call the function
   try
   {
      session->InvokeObjectFunction(pbobj, mid, &ci);
      // Was PB exception thrown?
      if (session->HasExceptionThrown())
      {
         // Handle PB exception
         session->ClearException();
      }
   }
   catch (...)
   {
      // Handle C++ exception
   }
   // Get the return value and print it to the console
   pbint ret = ci.returnValue->GetInt();
   fprintf(stderr, "The product of 123 and 45 is %i\n",
      ret);