trunc3
Round to integer, toward zero
Usage
#include <math.h>
double trunc(double x); float truncf(float x); long double truncl(long double x);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
trunc(), truncf(), truncl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
Library
Math library (libm, -lm)
Overview
These functions round x to the nearest integer value that is not larger in magnitude than x.
Return value
These functions return the rounded integer value, in floating format.
If x is integral, infinite, or NaN, x itself is returned.
Errors
No errors occur.
Attributes
For an explanation of the terms used in this section, see attributes(7).
| Interface | Attribute | Value |
| trunc(), truncf(), truncl() | Thread safety | MT-Safe |
Notes
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.
Releases
13 releases since Debian 3.0 (Woody); the text changed 12 times.