This function generates an audible alarm.

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

HWND     hwndDeskTop;  /*  Desktop-window handle. */
ULONG    flStyle;      /*  Alarm style. */
BOOL     rc;           /*  Alarm-generated indicator. */

rc = WinAlarm(hwndDeskTop, flStyle);