feraiseexcept

Parameters

excepts

Bitmask value: A combination (with bitwise OR) of any number of floating-point exception values supported by the implementation:

macro value	description
FE_DIVBYZERO	Pole error: division by zero, or some other asymptotically infinite result (from finite arguments).
FE_INEXACT	Inexact: the result is not exact.
FE_INVALID	Domain error: At least one of the arguments is a value for which the function is not defined.
FE_OVERFLOW	Overflow range error: The result is too large in magnitude to be represented as a value of the return type.
FE_UNDERFLOW	Underflow range error: The result is too small in magnitude to be represented as a value of the return type.
FE_ALL_EXCEPT	All exceptions (selects all of the exceptions supported by the implementation).

Certain library implementations may support additional floating-point exception values (with their corresponding macros also beginning with FE_).

Libraries may define in <fenv.h> only the macro values above they support (the others may not be defined).

At least all of the above macro values are defined in <cfenv> (even if not supported by the implementation).

Return Value

Example

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/* feraiseexcept example */
#include <stdio.h>      /* printf */
#include <fenv.h>       /* feraiseexcept, fetestexcept, FE_ALL_EXCEPT, FE_INVALID */
#pragma STDC FENV_ACCESS on
double fn (double x) {  /* some function for which zero is a domain error */
  if (x==0.0) feraiseexcept(FE_INVALID);
  return x;
}
int main ()
{
  feclearexcept (FE_ALL_EXCEPT);
  fn (0.0);
  if (fetestexcept(FE_INVALID)) printf ("FE_INVALID raised\n");
  return 0;
}

FE_INVALID raised

Data races

Exceptions

See also

feclearexcept

Clear floating-point exceptions (function)

fetestexcept

Test for floating-point exceptions (function)