libm/man/lround.3

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.\" $FreeBSD: src/lib/msun/man/lround.3,v 1.4 2005/06/15 19:04:04 ru Exp $
.\"
.Dd April 7, 2005
.Dt LROUND 3
.Os
.Sh NAME
.Nm llround ,
.Nm llroundf ,
.Nm llroundl ,
.Nm lround ,
.Nm lroundf ,
.Nm lroundl
.Nd "convert to nearest integral value"
.Sh LIBRARY
.Lb libm
.Sh SYNOPSIS
.In math.h
.Ft "long long"
.Fn llround "double x"
.Ft "long long"
.Fn llroundf "float x"
.Ft "long long"
.Fn llroundl "long double x"
.Ft long
.Fn lround "double x"
.Ft long
.Fn lroundf "float x"
.Ft long
.Fn lroundl "long double x"
.Sh DESCRIPTION
The
.Fn lround
function returns the integer nearest to its argument
.Fa x ,
rounding away from zero in halfway cases.
If the rounded result is too large to be represented as a
.Vt long
value, an invalid exception is raised and the return value is undefined.
Otherwise, if
.Fa x
is not an integer,
.Fn lround
may raise an inexact exception.
When the rounded result is representable as a
.Vt long ,
the expression
.Fn lround x
is equivalent to
.Po Vt long Pc Ns Fn round x
(although the former may be more efficient).
.Pp
The
.Fn llround ,
.Fn llroundf ,
.Fn llroundl ,
.Fn lroundf
and
.Fn lroundl
functions differ from
.Fn lround
only in their input and output types.
.Sh SEE ALSO
.Xr lrint 3 ,
.Xr math 3 ,
.Xr rint 3 ,
.Xr round 3
.Sh STANDARDS
The
.Fn llround ,
.Fn llroundf ,
.Fn llroundl ,
.Fn lround ,
.Fn lroundf ,
and
.Fn lroundl
functions conform to
.St -isoC-99 .
.Sh HISTORY
The
.Vt float
and
.Vt double
versions of these routines first appeared in
.Fx 5.4 .
The
.Vt "long double"
versions appeared in
.Fx 6.0 .