округлить до целого числа, в сторону нуля (round to integer, toward zero)
Имя (Name)
trunc, truncf, truncl - round to integer, toward zero
Синопсис (Synopsis)
#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
Описание (Description)
These functions round x to the nearest integer value that is not
larger in magnitude than x.
Возвращаемое значение (Return value)
These functions return the rounded integer value, in floating
format.
If x is integral, infinite, or NaN, x itself is returned.
Ошибки (Error)
No errors occur.
Версии (Versions)
These functions first appeared in glibc in version 2.1.
Атрибуты (Attributes)
For an explanation of the terms used in this section, see
attributes(7).
┌──────────────────────────────────────┬───────────────┬─────────┐
│Interface │ Attribute │ Value │
├──────────────────────────────────────┼───────────────┼─────────┤
│trunc(), truncf(), truncl() │ Thread safety │ MT-Safe │
└──────────────────────────────────────┴───────────────┴─────────┘
Стандарты (Conforming to)
C99, POSIX.1-2001, POSIX.1-2008.
Примечание (Note)
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.
Смотри также (See also)
ceil(3), floor(3), lrint(3), nearbyint(3), rint(3), round(3)
