Equivalent to the nextafter function, with exceptions noted in
    the Description.

    This function is supported on OpenVMS Integrity servers and
    Alpha only.

    Format

      #include  <math.h>

      double nexttoward  (double x, long double y);

      float nexttowardf  (float x, long double y);

      long double nexttowardl  (long double x, long double y);

1  –  Arguments

 x

    A real number.

 y

    A real number.

2  –  Description

    The nexttoward functions are equivalent to the corresponding
    nextafter functions, except that the second parameter has type
    long double and the functions return y converted to the type of
    the function if x equals y.

3  –  Return Values

    n                  The next representable floating-point value
                       following x in the direction of y.
    y (of the type x)  If x equals y.
    HUGE_VAL           Overflow; errno is set to ERANGE.
    NaN                x or y is NaN; errno is set to EDOM.