std::feholdexcept (3) - Linux Man Pages
Defined in header <cfenv>
int feholdexcept( std::fenv_t* envp ) (since C++11)
First, saves the current floating-point environment to the object pointed to by envp (similar to std::fegetenv), then clears all floating-point status flags, and then installs the non-stop mode: future floating-point exceptions will not interrupt execution (will not trap), until the floating-point environment is restored by std::feupdateenv or std::fesetenv.
This function may be used in the beginning of a subroutine that must hide the floating-point exceptions it may raise from the caller. If only some exceptions must be suppressed, while others must be reported, the non-stop mode is usually ended with a call to std::feupdateenv after clearing the unwanted exceptions.
envp - pointer to the object of type std::fenv_t where the floating-point environment will be stored
0 on success, non-zero otherwise.
feupdateenv restores the floating-point environment and raises the previously raise exceptions
fegetenv saves or restores the current floating point environment
FE_DFL_ENV default floating-point environment