trunc, truncf, truncl - round to integer, toward zero
#include <math.h>
double trunc(double x);
float truncf(float x);
long double truncl(long double x);
Link with -lm
.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
These functions round x
to the nearest integer not larger in absolute value.
These functions return the rounded integer value.
If x
is integral, infinite, or NaN, x
itself is returned.
No errors occur.
These functions first appeared in glibc in version 2.1.
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
trunc(), truncf(), truncl() | Thread safety | MT-Safe |
C99, POSIX.1-2001, POSIX.1-2008.
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.
This page is part of release 4.15 of the Linux man-pages
project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.