Causes the current process to become the focus for the Ctrl+C and Ctrl+Break signals.

#define INCL_DOSEXCEPTIONS
#include <os2.h>

BOOL32    flag;      /*  Focus flag. */
PULONG    pulTimes;  /*  The number of times DosSetSignalExceptionFocus has been called by the current process with flag set to SIG_SETFOCUS, minus the number of times it has been called with flag set to SIG_UNSETFOCUS. */
APIRET    ulrc;      /*  Return Code. */

ulrc = DosSetSignalExceptionFocus(flag, pulTimes);