Saves the currently raised floating-point exceptions, restores the specified floating-point environment state, and then raises the saved floating-point exceptions.
int feupdateenv( const fenv_t* penv );
Pointer to a fenv_t object that contains a floating-point environment as set by a call to fegetenv or feholdexcept. You can also specify the default startup floating-point environment by using the FE_DFL_ENV macro.
Returns 0 if all actions completed successfully. Otherwise, returns a nonzero value.
The feupdateenv function performs multiple actions. First, it stores the current raised floating-point exception status flags in automatic storage. Then, it sets the current floating-point environment from the value stored in the fenv_t object pointed to by penv. If penv is not FE_DFL_ENV or does not point to a valid fenv_t object, subsequent behavior is undefined. Finally, feupdateenv raises the locally stored floating-point exceptions.
To use this function, you must turn off floating-point optimizations that could prevent access by using the
#pragma fenv_access(on) directive prior to the call. For more information, see fenv_access.
|Function||C header||C++ header|
For additional compatibility information, see Compatibility.