std:: fegetenv, std:: fesetenv

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fegetenv fesetenv
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Defined in header <cfenv>
int fegetenv ( std:: fenv_t * envp )
(1) (since C++11)
int fesetenv ( const std:: fenv_t * envp ) ;
(2) (since C++11)

Manages the status of the floating-point environment.

1) Attempts to store the status of the floating-point environment in the object pointed to by envp .
2) Attempts to establish the floating-point environment from the object pointed to by envp . The value of that object must be previously obtained by a call to std::feholdexcept or std::fegetenv or be a floating-point macro constant. If any of the floating-point status flags are set in envp , they become set in the environment (and are then testable with std::fetestexcept ), but the corresponding floating-point exceptions are not raised (execution continues uninterrupted)

Parameters

envp - pointer to the object of type std:: fenv_t which holds the status of the floating-point environment

Return value

​ 0 ​ on success, non-zero otherwise.

See also

(C++11)
saves the environment, clears all status flags and ignores all future errors
(function)
(C++11)
restores the floating-point environment and raises the previously raised exceptions
(function)
(C++11)
default floating-point environment
(macro constant)
C documentation for fegetenv , fesetenv
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