protected:
      /**
       *  @if maint
       *  Place to stash in || out || in | out settings for current stringbuf.
       *  @endif
      */
      ios_base::openmode 	_M_mode;

      // Data Members:
      /**
       *  @if maint
       *  @doctodo
       *  @endif
      */
      __string_type 		_M_string