trunc

TRUNC(3)                   Linux Programmer's Manual                  TRUNC(3)

NAME
       trunc, truncf, truncl - round to integer, toward zero

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

DESCRIPTION
       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.

VERSIONS
       These functions first appeared in glibc in version 2.1.

ATTRIBUTES
       For an  explanation  of  the  terms  used  in  this  section,  see  at-
       tributes(7).

       +----------------------------+---------------+---------+
       |Interface                   | Attribute     | Value   |
       +----------------------------+---------------+---------+
       |trunc(), truncf(), truncl() | Thread safety | MT-Safe |
       +----------------------------+---------------+---------+
CONFORMING TO
       C99, POSIX.1-2001, POSIX.1-2008.

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.

SEE ALSO
       ceil(3), floor(3), lrint(3), nearbyint(3), rint(3), round(3)

COLOPHON
       This  page  is  part of release 5.05 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/.

                                  2019-03-06                          TRUNC(3)