home | help 
std::feclearexcept(3)	       C++ Standard Libary	   std::feclearexcept(3)

NAME
     std::feclearexcept - std::feclearexcept

Synopsis
	Defined in header <cfenv>
	int feclearexcept( int excepts );  (since C++11)

	Attempts  to  clear the floating-point exceptions that are listed in the
     bitmask
	argument excepts, which is a bitwise OR of the floating point  exception
     macros.

Parameters
	excepts - bitmask listing the exception flags to clear

Return value
	0 if all indicated exceptions were successfully cleared or if excepts is
     zero.
	Returns a non-zero value on error.

Example
     // Run this code

      #include <cfenv>
      #include <cmath>
      #include <iostream>

      // #pragma STDC FENV_ACCESS ON

      volatile	double	zero  = 0.0; // volatile not needed where FENV_ACCESS is
     supported
      volatile double one = 1.0;  // volatile not needed  where  FENV_ACCESS  is
     supported

      int main()
      {
	  std::feclearexcept(FE_ALL_EXCEPT);
	  std::cout <<	"1.0/0.0 = " << 1.0 / zero << '\n';
	  if (std::fetestexcept(FE_DIVBYZERO))
	      std::cout << "division by zero reported\n";
	  else
	      std::cout << "division by zero not reported\n";

	  std::feclearexcept(FE_ALL_EXCEPT);
	  std::cout << "1.0/10 = " << one / 10 << '\n';
	  if (std::fetestexcept(FE_INEXACT))
	      std::cout << "inexact result reported\n";
	  else
	      std::cout << "inexact result not reported\n";

	  std::feclearexcept(FE_ALL_EXCEPT);
	  std::cout << "sqrt(-1) = " << std::sqrt(-1) << '\n';
	  if (std::fetestexcept(FE_INVALID))
	      std::cout << "invalid result reported\n";
	  else
	      std::cout << "invalid result not reported\n";
      }

Possible output:
      1.0/0.0 = inf
      division by zero reported
      1.0/10 = 0.1
      inexact result reported
      sqrt(-1) = -nan
      invalid result reported

See also
	fetestexcept  determines  which  of  the specified floating-point status
     flags are set
	(C++11)      (function)
	C documentation for
	feclearexcept

http://cppreference.com 	   2024.06.10		   std::feclearexcept(3)
home | help