The CCI_GET_RESULT_INFO_CLASS_NAME macro gets the index -th column's class name of a prepared SELECT statement. It does not check whether the specified argument, res_info, is NULL and whether index is valid. You cannot delete the returned memory pointer with free(). The return value can be NULL.
#define CCI_GET_RESULT_INFO_CLASS_NAME(T_CCI_COL_INFO* res_info, int index)