1.\" $OpenBSD: fegetround.3,v 1.3 2013/06/05 03:40:26 tedu Exp $ 2.\" 3.\" Copyright (c) 2011 Martynas Venckus <martynas@openbsd.org> 4.\" 5.\" Permission to use, copy, modify, and distribute this software for any 6.\" purpose with or without fee is hereby granted, provided that the above 7.\" copyright notice and this permission notice appear in all copies. 8.\" 9.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16.\" 17.Dd $Mdocdate: June 5 2013 $ 18.Dt FEGETROUND 3 19.Os 20.Sh NAME 21.Nm fegetround , 22.Nm fesetround 23.Nd control floating-point rounding direction modes 24.Sh SYNOPSIS 25.In fenv.h 26.Ft int 27.Fn fegetround void 28.Ft int 29.Fn fesetround "int round" 30.Sh DESCRIPTION 31These functions provide control of floating-point rounding direction 32modes. 33The 34.Fa round 35input argument is a value specifying a rounding direction mode and 36containing any of the values listed below. 37.Bl -tag -width ".Dv FE_TOWARDZERO" 38.It Dv FE_TONEAREST 39Results are rounded to the closest representable value. 40If the exact result is exactly half way between two representable 41values, the value whose last binary digit is even (zero) is chosen. 42This is the default mode. 43.It Dv FE_DOWNWARD 44Results are rounded towards negative \*[If]. 45.It Dv FE_UPWARD 46Results are rounded towards positive \*[If]. 47.It Dv FE_TOWARDZERO 48Results are rounded towards zero. 49.El 50.Pp 51The 52.Fn fegetround 53function gets the current rounding direction. 54.Pp 55The 56.Fn fesetround 57function establishes the rounding direction represented by 58.Pa round . 59If the argument is not equal to the value of a rounding direction 60macro, the rounding direction is not changed. 61.Sh RETURN VALUES 62The 63.Fn fegetround 64function returns the current rounding direction. 65The 66.Fn fesetround 67function return zero on success, and non-zero if an error occurred. 68.Sh SEE ALSO 69.Xr feclearexcept 3 , 70.Xr feenableexcept 3 , 71.Xr fegetenv 3 72.Sh STANDARDS 73The 74.Fn fegetround 75and 76.Fn fesetround 77functions conform to 78.St -isoC-99 . 79.Sh HISTORY 80These functions first appeared in 81.Ox 5.0 . 82