private String DDCRET_String(int retcode)
   {
   	 switch ( retcode )
   	 {
	  case DDC_SUCCESS:          return "DDC_SUCCESS";
	  case DDC_FAILURE:          return "DDC_FAILURE";
	  case DDC_OUT_OF_MEMORY:    return "DDC_OUT_OF_MEMORY";
	  case DDC_FILE_ERROR:       return "DDC_FILE_ERROR";
	  case DDC_INVALID_CALL:     return "DDC_INVALID_CALL";
	  case DDC_USER_ABORT:       return "DDC_USER_ABORT";
	  case DDC_INVALID_FILE:     return "DDC_INVALID_FILE";
     }
     return "Unknown Error";   
   }