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NAME

       trunc, truncf, truncl - round to integer, towards 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(): _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or
       cc -std=c99

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.

CONFORMING TO

       C99, POSIX.1-2001.

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 3.24 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/.

                                  2008-08-11                          TRUNC(3)