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 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 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)