# LROUND

NAME

SYNOPSIS

DESCRIPTION

RETURN VALUE

ERRORS

VERSIONS

ATTRIBUTES

CONFORMING TO

SEE ALSO

COLOPHON

## NAME

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

## 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:

_ISOC99_SOURCE ||
_POSIX_C_SOURCE >= 200112L

## DESCRIPTION

These functions
round their argument to the nearest integer value, rounding
halfway cases 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

For an
explanation of the terms used in this section, see
**attributes**(7).

## CONFORMING TO

C99,
POSIX.1-2001, POSIX.1-2008.

## SEE ALSO

**ceil**(3),
**floor**(3), **lrint**(3), **nearbyint**(3),
**rint**(3), **round**(3)

## COLOPHON

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