This example shows how to set the current thread to be the focus for the Ctrl+C and Ctrl+Break signals.
#define INCL_DOSPROCESS /* DOS process values (for DosSleep) */ #define INCL_DOSEXCEPTIONS /* DOS exception values */ #define INCL_ERRORS /* DOS error values */ #include <os2.h> #include <stdio.h> ULONG _System MyTermHandler( PEXCEPTIONREPORTRECORD p1, PEXCEPTIONREGISTRATIONRECORD p2, PCONTEXTRECORD p3, PVOID pv ); int main (VOID) { EXCEPTIONREGISTRATIONRECORD RegRec = {0}; /* Exception Registration Record */ APIRET rc = NO_ERROR; /* Return code*/ /* Add MyTermHandler to this thread's chain of exception handlers */ RegRec.ExceptionHandler = (ERR)MyTermHandler; rc = DosSetExceptionHandler( &RegRec ); if (rc != NO_ERROR) { printf("DosSetExceptionHandler error: return code = %u\n",rc); return 1; } printf("Terminate this program using Ctrl-C or Ctrl-Break.\n"); rc = DosSleep(60000L); /* Give user plenty of time to comply... */ rc = DosUnsetExceptionHandler( &RegRec ); if (rc != NO_ERROR) { printf("DosUnsetExceptionHandler error: return code = %u\n",rc); return 1; } return NO_ERROR; } /***************************************************************************/ ULONG _System MyTermHandler( PEXCEPTIONREPORTRECORD p1, PEXCEPTIONREGISTRATIONRECORD p2, PCONTEXTRECORD p3, PVOID pv ) { ULONG ulCount = 0; /* Count of API calls */ APIRET rc = NO_ERROR; /* Return code */ printf("*** MyTermHandler entered: ExceptionNum = %x\n",p1->ExceptionNum); rc = DosSetSignalExceptionFocus( SIG_UNSETFOCUS, &ulCount); if (rc != NO_ERROR) { printf("DosSetSignalExceptionFocus error: return code = %u\n", rc); return 1; } /**************************************/ /* Handle XCPT_SIGNAL exceptions here */ /**************************************/ rc = DosSetSignalExceptionFocus( SIG_SETFOCUS, &ulCount); if (rc != NO_ERROR) { printf("DosSetSignalExceptionFocus error: return code = %u\n", rc); return 1; } return XCPT_CONTINUE_SEARCH; /* Exception not resolved... */ }