#include <math.h>float nexttowardf(float from, long double towards); double nexttoward(double from, long double towards); long double nexttowardl(long double from, long double towards);
nexttoward( ), nexttowardf( ), and nexttowardl( ) were defined by C99.
The nexttoward( ) family of functions returns the next value after from that is closer to towards. They are the same as the nextafter( ) family, except that towards is a long double for all three functions.
A related function is nextafter( ).