#define _GNU_SOURCE /* See feature_test_macros(7) */ #include <math.h> double nextup(double x); float nextupf(float x); long double nextupl(long double x); double nextdown(double x); float nextdownf(float x); long double nextdownl(long double x);
If x is the smallest representable negative number in the corresponding type, these functions return -0. If x is 0, the returned value is the smallest representable positive number of the corresponding type.
If x is positive infinity, the returned value is positive infinity. If x is negative infinity, the returned value is the largest representable finite negative number of the corresponding type.
If x is Nan, the returned value is NaN.
The value returned by nextdown(x) is -nextup(-x), and similarly for the other types.
Interface | Attribute | Value |
nextup(), nextupf(), nextupl(), nextdown(), nextdownf(), nextdownl() | Thread safety | MT-Safe |