| NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | VERSIONS | CONFORMING TO | NOTES | SEE ALSO | COLOPHON | The Linux Programming Interface |
TRUNC(3) Linux Programmer's Manual TRUNC(3)
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():
_XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
or cc -std=c99
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.
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)
This page is part of release 3.32 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
2010-09-20 TRUNC(3)
HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface