trunc - Man Page

Math library (libm, -lm)

#include <math.h>

double trunc(double x);
float truncf(float x);
long double truncl(long double x);

trunc(), truncf(), truncl():

    _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

These functions round x to the nearest integer value that is not larger in magnitude than x.

These functions return the rounded integer value, in floating format.

If x is integral, infinite, or NaN, x itself is returned.

No errors occur.

For an explanation of the terms used in this section, see attributes(7).

C11, POSIX.1-2008.

glibc 2.1. C99, POSIX.1-2001.

The integral value returned by these functions may be too large to store in an integer type (int, long, etc.). To avoid an overflow, which will produce undefined results, an application should perform a range check on the returned value before assigning it to an integer type.

ceil(3), floor(3), lrint(3), nearbyint(3), rint(3), round(3)

ceil(3), floor(3), rint(3), round(3).

The man pages truncf(3) and truncl(3) are aliases of trunc(3).