Listing 2 The header <fenv.h>

typedef T fenv_t;
typedef T fexcept_t;

#define FE_INEXACT     val
#define FE_DIVBYZERO   val
#define FE_UNDERDFLOW  val
#define FE_OVERFLOW    val
#define FE_INVALID     val
#define FE_ALL_EXCEPT  val

#define FE_TONEAREST   val
#define FE_UPWARD      val
#define FE_DOWNWARD    val
#define FE_TOWARDZERO  val

#define FE_DFL_ENV     ptr

void feclearexcept(int excepts);
void fegetexcept(fexcept_t *flagp, int excepts);
void feraiseexcept(int excepts);
void fesetexcept(const fexcept_t *flagp, int excepts);
int fetestexcept(int excepts);
int fegetround(void);
int fesetround(int round);
void fegetenv(fenv_t *envp);
int feholdexcept(fenv_t *envp);
void fesetenv(const fenv_t *envp);
void feupdateenv(const fenv_t *envp);
/* End of File */