Function            MMickeysMovedx - number of mickeys mouse moved
                                         horizontally

  Syntax              int MMickeysMovedx(void);

  Prototype in        mousehk.h

  Remarks             determines the number of mickeys the mouse has
                      moved horizontally since the last call.

                      _mouse3 contains the number of mickeys the mouse
                      has moved horizontally since the last call.

                      _mouse4 contains the number of mickeys the mouse
                      has moved vertically since the last call.

  Return value        returns the number of mickeys the mouse has moved
                      horizontally since the last call.

  Note                positive values indicate down/right.

  See also            MMickeysMovedy()

  Example             see demomous.c