This function sets a text string in a dialog item.

#define INCL_WINDIALOGS /* Or use INCL_WIN, INCL_PM, Also in COMMON section */
#include <os2.h>

HWND     hwndDlg;  /*  Parent-window handle. */
ULONG    idItem;   /*  Identity of the child window whose text is to be set. */
PSZ      pszText;  /*  Source string. */
BOOL     rc;       /*  Success indicator. */

rc = WinSetDlgItemText(hwndDlg, idItem, pszText);