This example unwinds all handlers. It does not resolve the exception and causes a SYSTEM ERROR pop-up for the exception to be displayed.

#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");
  printf("You will get a System Error popup for the exception.\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 )
{
  APIRET  rc = NO_ERROR;

  printf("*** MyTermHandler entered: ExceptionNum = %x\n",p1->ExceptionNum);

  rc = DosUnsetExceptionHandler( p2 );  /* Stop recursive entry to handler */
  rc = DosUnwindException( p2,          /* Exception Registration Record */
                           (PVOID) 0,   /* BAD ADDRESS!!! */
                           p1);         /* Exception Report Record */
  if (rc != NO_ERROR) {
     printf("DosUnwindException error:  return code = %u\n", rc);
  }

  return XCPT_CONTINUE_SEARCH;
}