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