This call sets the desktop-pointer handle.

#define INCL_WINPOINTERS /* Or use INCL_WIN, INCL_PM, */
#include <os2.h>

HWND        hwndDeskTop;     /*  Desktop-window handle. */
HPOINTER    hptrNewPointer;  /*  New pointer handle. */
BOOL        rc;              /*  Pointer-updated indicator. */

rc = WinSetPointer(hwndDeskTop, hptrNewPointer);