Rounds to the nearest integer value.
#include <math.h>
long lround (x)
double x;
long lroundf (x)
float x;
long lroundl (x)
long double x;
long lroundd32(x)
_Decimal32 x;
long lroundd64(x)
_Decimal64 x;
long lroundd128(x)
_Decimal128 x;The lround, lroundf, lroundl, lroundd32, lroundd64, and lroundd128 subroutines round the x parameter to the nearest integer value, rounding halfway cases away from zero, regardless of the current rounding direction.
An application wishing to check for error situations should set the errno global variable to zero and call feclearexcept(FE_ALL_EXCEPT) before calling these subroutines. Upon return, if errno is nonzero or fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is nonzero, an error has occurred.
| Item | Description |
|---|---|
| x | Specifies the value to be rounded. |
Upon successful completion, the lround, lroundf, lroundl, lroundd32, lroundd64, and lroundd128 subroutines return the rounded integer value.
If x is NaN, a domain error occurs and an unspecified value is returned.
If x is +Inf, a domain error occurs and an unspecified value is returned.
If x is -Inf, a domain error occurs and an unspecified value is returned.
If the correct value is positive and too large to represent as a long, a domain error occurs and an unspecified value is returned.
If the correct value is negative and too large to represent as a long, a domain error occurs and an unspecified value is returned.