2003-02-11 22:56:21 +01:00
|
|
|
.\" Copyright (c) 2003 Mike Barcroft <mike@FreeBSD.org>
|
|
|
|
|
.\" All rights reserved.
|
|
|
|
|
.\"
|
|
|
|
|
.\" 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 AUTHOR 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 AUTHOR 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.
|
|
|
|
|
.\"
|
|
|
|
|
.\" $FreeBSD$
|
|
|
|
|
.\"
|
2004-07-19 10:16:10 +02:00
|
|
|
.Dd July 18, 2004
|
2003-02-12 04:29:39 +01:00
|
|
|
.Dt SIGNBIT 3
|
2003-02-11 22:56:21 +01:00
|
|
|
.Os
|
|
|
|
|
.Sh NAME
|
|
|
|
|
.Nm signbit
|
|
|
|
|
.Nd "determine whether a floating-point number's sign is negative"
|
|
|
|
|
.Sh LIBRARY
|
2004-07-19 10:16:10 +02:00
|
|
|
.Lb libm
|
2003-02-11 22:56:21 +01:00
|
|
|
.Sh SYNOPSIS
|
|
|
|
|
.In math.h
|
|
|
|
|
.Ft int
|
|
|
|
|
.Fn signbit "real-floating x"
|
|
|
|
|
.Sh DESCRIPTION
|
|
|
|
|
The
|
|
|
|
|
.Fn signbit
|
|
|
|
|
macro takes an argument of
|
2003-02-24 23:53:26 +01:00
|
|
|
.Fa x
|
2003-02-11 22:56:21 +01:00
|
|
|
and returns non-zero if the value of its sign is negative, otherwise 0.
|
|
|
|
|
.Sh SEE ALSO
|
|
|
|
|
.Xr fpclassify 3 ,
|
|
|
|
|
.Xr math 3
|
|
|
|
|
.Sh STANDARDS
|
|
|
|
|
The
|
|
|
|
|
.Fn signbit
|
|
|
|
|
macro conforms to
|
|
|
|
|
.St -isoC-99 .
|
|
|
|
|
.Sh HISTORY
|
|
|
|
|
The
|
|
|
|
|
.Fn signbit
|
|
|
|
|
macro was added in
|
|
|
|
|
.Fx 5.1 .
|
