c99 [ flag... ] file... -lm [ library... ] #include <math.h>
double rint(double x);
float rintf(float x);
long double rintl(long double x);
These functions return the integral value (represented as a double) nearest x in the direction of the current rounding mode.
If the current rounding mode rounds toward negative infinity, rint() is equivalent to floor(3M). If the current rounding mode rounds toward positive infinity, rint() is equivalent to ceil(3M).
These functions differ from the nearbyint(3M), nearbyintf(), and nearbyintl() functions only in that they might raise the inexact floating-point exception if the result differs in value from the argument.
Upon successful completion, these functions return the integer (represented as a double precision number) nearest x in the direction of the current rounding mode.
If x is NaN, a NaN is returned.
If x is ±0 or ±Inf, x is returned.
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
Interface Stability | Standard |
MT-Level | MT-Safe |
abs(3C), ceil(3M), feclearexcept(3M), fetestexcept(3M), floor(3M), isnan(3M), math.h(3HEAD), nearbyint(3M), attributes(5), standards(5)