This patch imports the unmodified current version of NetBSD libc. The NetBSD includes are in /nbsd_include, while the libc code itself is split between lib/nbsd_libc and common/lib/libc.
140 lines
3.8 KiB
Groff
140 lines
3.8 KiB
Groff
.\" $NetBSD: fpgetmask.3,v 1.10 2008/04/30 13:10:50 martin Exp $
|
|
.\"
|
|
.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" This code is derived from software contributed to The NetBSD Foundation
|
|
.\" by Ross Harvey.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
|
|
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
|
|
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
|
|
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
.\" POSSIBILITY OF SUCH DAMAGE.
|
|
.\"
|
|
.Dd April 4, 2004
|
|
.Dt FPGETMASK 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm fpgetmask ,
|
|
.Nm fpgetround ,
|
|
.Nm fpgetsticky ,
|
|
.Nm fpsetmask ,
|
|
.Nm fpsetround ,
|
|
.Nm fpsetsticky
|
|
.Nd IEEE FP mode control
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In ieeefp.h
|
|
.Ft fp_except
|
|
.Fn fpgetmask void
|
|
.Ft fp_rnd
|
|
.Fn fpgetround void
|
|
.Ft fp_except
|
|
.Fn fpgetsticky void
|
|
.Ft fp_except
|
|
.Fn fpsetmask fp_except\ mask
|
|
.Ft fp_rnd
|
|
.Fn fpsetround fp_rnd\ rnd_dir
|
|
.Ft fp_except
|
|
.Fn fpsetsticky fp_except\ sticky
|
|
.Sh DESCRIPTION
|
|
A rounding mode is one of
|
|
.Dv FP_RZ , FP_RM , FP_RN ,
|
|
or
|
|
.Dv FP_RP ,
|
|
for rounding towards zero, rounding
|
|
.Pq Em Minus infinity
|
|
down, rounding to
|
|
.Em nearest ,
|
|
and rounding
|
|
.Pq Em Plus infinity
|
|
up.
|
|
The default mode is
|
|
.Dv FP_RN .
|
|
.Pp
|
|
An
|
|
.Ft fp_except
|
|
value is a bitmask specifying an exception type and containing any of
|
|
the values listed below.
|
|
.Bl -column -offset indent FP_X_UFLxx
|
|
.It Dv FP_X_INV Ta Invalid\ Operation
|
|
.It Dv FP_X_DZ Ta Division\ by\ zero
|
|
.It Dv FP_X_OFL Ta Overflow
|
|
.It Dv FP_X_UFL Ta Underflow
|
|
.It Dv FP_X_IMP Ta Imprecision (inexact)
|
|
.It Dv FP_X_IOV Ta Integer\ Overflow
|
|
.El
|
|
.Pp
|
|
The
|
|
.Fn fpsetmask
|
|
function will set the current exception mask, i.e., it will cause
|
|
future operations with the specified result status to raise the
|
|
.Dv SIGFPE
|
|
exception.
|
|
The
|
|
.Fn fpgetmask
|
|
function will return the current exception mask.
|
|
.Pp
|
|
The
|
|
.Fn fpsetround
|
|
function will cause future operations to use the specified dynamic
|
|
rounding mode.
|
|
The
|
|
.Fn fpgetround
|
|
function will return the current rounding mode.
|
|
.Bl -tag -width Note:x
|
|
.It Em Note :
|
|
On some architectures, instructions can optionally specify static
|
|
rounding modes and exception enables that will supersede the specified
|
|
dynamic mode.
|
|
On other architectures, these features may not be fully supported.
|
|
.El
|
|
.Pp
|
|
A
|
|
.Dq sticky
|
|
status word may be maintained in which a bit is set every time an
|
|
exceptional floating point condition is encountered, whether or not a
|
|
.Dv SIGFPE
|
|
is generated.
|
|
The
|
|
.Fn fpsetsticky
|
|
function will set or clear the specified exception history bits.
|
|
The
|
|
.Fn fpgetsticky
|
|
function will return the exception history bits.
|
|
.Sh RETURN VALUES
|
|
The
|
|
.Fn fpgetround
|
|
and
|
|
.Fn fpsetround
|
|
functions return the
|
|
.Pq previous
|
|
rounding mode.
|
|
The
|
|
.Fn fpgetmask ,
|
|
.Fn fpsetmask ,
|
|
.Fn fpgetsticky ,
|
|
and
|
|
.Fn fpsetsticky
|
|
functions return the
|
|
.Pq previous
|
|
exception mask and exception history bits.
|
|
.Sh SEE ALSO
|
|
.Xr sigaction 2
|