This function sets a number of bits into the memory of the reserved window words.

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

HWND     hwnd;    /*  Window handle. */
LONG     index;   /*  Zero-based index of the value to be set. */
ULONG    flData;  /*  Bit data to store in the window words. */
ULONG    flMask;  /*  Bits to be written indicator. */
BOOL     rc;      /*  Success indicator. */

rc = WinSetWindowBits(hwnd, index, flData,
       flMask);