Man Linux: Main Page and Category List

NAME

       lround,  lroundf,  lroundl,  llround,  llroundf,  llroundl  -  round to
       nearest integer, away from zero

SYNOPSIS

       #include <math.h>

       long int lround(double x);
       long int lroundf(float x);
       long int lroundl(long double x);

       long long int llround(double x);
       long long int llroundf(float x);
       long long int llroundl(long double x);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       All functions shown above: _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or
       cc -std=c99

DESCRIPTION

       These  functions  round  their  argument  to the nearest integer value,
       rounding away from zero, regardless of the current  rounding  direction
       (see fenv(3)).

       Note  that  unlike  round(3),  ceil(3),  etc., the return type of these
       functions differs from that of their arguments.

RETURN VALUE

       These functions return the rounded integer value.

       If x is a NaN or an infinity, or the rounded value is too large  to  be
       stored  in  a  long (long long in the case of the ll* functions) then a
       domain error occurs, and the return value is unspecified.

ERRORS

       See math_error(7) for information on how to determine whether an  error
       has occurred when calling these functions.

       The following errors can occur:

       Domain error: x is a NaN or infinite, or the rounded value is too large
              An invalid floating-point exception (FE_INVALID) is raised.

       These functions do not set errno.

VERSIONS

       These functions first appeared in glibc in version 2.1.

CONFORMING TO

       C99, POSIX.1-2001.

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