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.\"     from: @(#)rint.3	5.1 (Berkeley) 5/2/91
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.Dd January 13, 2008
.Dt RINT 3
.Os
.Sh NAME
.Nm nearbyint ,
.Nm nearbyintf ,
.Nm nearbyintl ,
.Nm rint ,
.Nm rintf ,
.Nm rintl
.Nd round to integral value in floating-point format
.Sh LIBRARY
.Lb libm
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn nearbyint "double x"
.Ft float
.Fn nearbyintf "float x"
.Ft long double
.Fn nearbyintl "long double x"
.Ft double
.Fn rint "double x"
.Ft float
.Fn rintf "float x"
.Ft long double
.Fn rintl "long double x"
.Sh DESCRIPTION
The
.Fn rint ,
.Fn rintf ,
and
.Fn rintl
functions return the integral value nearest to
.Fa x
according to the prevailing rounding mode.
These functions raise an inexact exception when the original argument
is not an exact integer.
.Pp
The
.Fn nearbyint ,
.Fn nearbyintf ,
and
.Fn nearbyintl
functions perform the same operation, except that they do not raise
an inexact exception.
.Sh SEE ALSO
.Xr abs 3 ,
.Xr ceil 3 ,
.Xr fabs 3 ,
.Xr fenv 3 ,
.Xr floor 3 ,
.Xr ieee 3 ,
.Xr lrint 3 ,
.Xr lround 3 ,
.Xr math 3 ,
.Xr round 3
.Sh STANDARDS
These functions conform to
.St -isoC-99 .
.Sh HISTORY
A
.Fn rint
function appeared in
.At v6 .
The
.Fn nearbyint
and
.Fn nearbyintf
functions appeared in
.Fx 5.3 ,
and the long double variants were first available in
.Fx 8.0 .