1.\" $NetBSD: isinf.3,v 1.3 1995/02/27 04:34:56 cgd Exp $ 2.\" 3.\" Copyright (c) 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)isinf.3 8.2 (Berkeley) 1/29/94 35.\" 36.Dd January 29, 1994 37.Dt ISINF 3 38.Os 39.Sh NAME 40.Nm isinf , 41.Nm isnan 42.Nd test for infinity or not-a-number 43.Sh SYNOPSIS 44.Ft int 45.Fn isinf double 46.Ft int 47.Fn isnan double 48.Sh DESCRIPTION 49The 50.Fn isninf 51function 52returns 1 if the number is 53.Dq \\*(If , 54otherwise 0. 55.Pp 56The 57.Fn isnan 58function 59returns 1 if the number is 60.Dq not-a-number , 61otherwise 0. 62.Sh SEE ALSO 63.Xr math 3 64.Rs 65.%T "IEEE Standard for Binary Floating-Point Arithmetic" 66.%Q ANSI 67.%R Std 754-1985 68.Re 69.Sh BUGS 70Neither the 71.Tn VAX 72nor the Tahoe floating point have distinguished values 73for either infinity or not-a-number. 74These routines always return 0 on those architectures. 75