User-button data structure.

typedef struct _USERBUTTON {
  HWND      hwnd;        /*  Window handle. */
  HPS       hps;         /*  Presentation-space handle. */
  ULONG     fsState;     /*  New state of user button. */
  ULONG     fsStateOld;  /*  Old state of user button. */
} USERBUTTON;

typedef   USERBUTTON   * PUSERBUTTON ;