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fpOper_usingStatus(void) {
  /* ... */
  double a = 1e-40, b, c;
  float x = 0, y;
  unsigned int rv = _clearfp() ;

  /* Store into y is inexact and underflows: */
  y = a;
  rv = _clearfp() ;  /* rv has _SW_INEXACT and _SW_UNDERFLOW */

  /* zero-divide */
  b = y / x; rv = _clearfp() ; /* rv has _SW_ZERODIVIDE */

  /* inexact */
  c = sin(30) * a; rv = _clearfp() ; /* rv has _SW_INEXACT */
  /* ... */
}

fp_usingSEH(void) {
  /* ... */
  double a = 1e-40, b, c = 0.1;
  float x = 0, y;
  unsigned int rv ;

  unmask_fp();

  _try {
    /* Store into y is inexact and underflows */
    y = a;

    /* divide by zero operation */
    b = y / x;

    /* inexact */
    c = sin(30) * a;
  }

  _except (_fpieee_flt (
             GetExceptionCode(), 
             GetExceptionInformation(), 
             fpieee_handler)) 
  {
	printf ("fpieee_handler: EXCEPTION_EXECUTE_HANDLER");
  }

  /* ... */
}

void unmask_fpsr(void) {
  unsigned int u;
  unsigned int control_word;
  _controlfp_s(&control_word, 0, 0);
  u = control_word & ~(_EM_INVALID 
                    \| _EM_DENORMAL 
                    \| _EM_ZERODIVIDE 
                    \| _EM_OVERFLOW 
                    \| _EM_UNDERFLOW 
                    \| _EM_INEXACT);
  _controlfp_s( &control_word, u, _MCW_EM);
  return ;
}

int fpieee_handler(_FPIEEE_RECORD *ieee) {
  /* ... */

  switch (ieee->RoundingMode) {
    case _FpRoundNearest:
      /* ... */
      break;

      /* Other RMs include _FpRoundMinusInfinity, 
       * _FpRoundPlusInfinity, _FpRoundChopped */
    
      /* ... */
    }

  switch (ieee->Precision) {
    case _FpPrecision24:
      /* ... */
      break;

      /* Other Ps include _FpPrecision53*/
      /* ... */
    }

   switch (ieee->Operation) {
     case _FpCodeAdd:
       /* ... */
       break;

       /* Other Ops include _FpCodeSubtract, _FpCodeMultiply, 
        * _FpCodeDivide, _FpCodeSquareRoot, _FpCodeCompare, 
        * _FpCodeConvert, _FpCodeConvertTrunc */
       /* ... */
    }

  /* process the bitmap ieee->Cause */
  /* process the bitmap ieee->Enable */
  /* process the bitmap ieee->Status */
  /* process the Operand ieee->Operand1, 
   * evaluate format and Value */
  /* process the Operand ieee->Operand2, 
   *evaluate format and Value */
  /* process the Result ieee->Result, 
   * evaluate format and Value */
  /* theThe result should be set according to the operation 
   * specified in ieee->Cause and the result format as 
   * specified in ieee->Result */
  /* the Result set is based on the */
  /* ... */
}