void XConvertCase(keysym, lower_return, upper_return)
      KeySym keysym;
      KeySym *lower_return;
      KeySym *upper_return;
| keysym | Specifies the KeySym that is to be converted. | 
| lower_return | Returns the lowercase form of keysym, or keysym. | 
| upper_return | Returns the uppercase form of keysym, or keysym. |