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 not larger in absolute value.

RETURN VALUE

       These functions return the rounded integer value.

       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 attributes(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 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/.

                                            2017-09-15                                   TRUNC(3)