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



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 || _POSIX_C_SOURCE >= 200112L;
           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 the round(3) and ceil(3), functions, 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.

ATTRIBUTES
   Multithreading (see pthreads(7))
       The  lround(),  lroundf(),  lroundl(), llround(), llroundf(), and llroundl() functions are
       thread-safe.

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 3.74 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 http://www.kernel.org/doc/man-pages/.



                                            2013-08-26                                  LROUND(3)