fesetenv

You can use the fesetenv function to restore the floating-point environment.

void fesetenv (const fenv_t *envp);

envp

A pointer to a word containing the value to which the environment should be set.

DESCRIPTION

The fesetenv function sets the floating-point environment to the value pointed to by its argument envp. The value of envp must come from a call to either fegetenv or feholdexcept, or it may be the constant FE_DFL_ENV, which specifies the default environment. In the default environment, all exception flags are clear and the rounding direction is set to the default.

EXAMPLES

double_t func (double_t x, double_t y)
{
   fenv_t *env;

   fesetenv(FE_DFL_ENV);      /* clear environment */

   x = x + y;        /* floating-point op; may raise exceptions */
   fegetenv(env);    /* save state of env after add */

   y = y * x;        /* floating-point op; may raise exceptions */
   fesetenv(env);    /* ignore environmental changes by
                        multiplication operator */
   .
   .
   .
}