1.\" $NetBSD: nan.3,v 1.1 2006/03/15 22:07:09 kleink Exp $ 2.\" 3.\" Copyright (c) 2006 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Klaus Klein. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the NetBSD 20.\" Foundation, Inc. and its contributors. 21.\" 4. Neither the name of The NetBSD Foundation nor the names of its 22.\" contributors may be used to endorse or promote products derived 23.\" from this software without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 29.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35.\" POSSIBILITY OF SUCH DAMAGE. 36.\" 37.Dd March 15, 2006 38.Dt NAN 3 39.Os 40.Sh NAME 41.Nm nan , 42.Nm nanf , 43.Nm nanl 44.Nd return quiet NaN 45.Sh LIBRARY 46.Lb libm 47.Sh SYNOPSIS 48.In math.h 49.Ft double 50.Fn nan "const char *tagp" 51.Ft float 52.Fn nanf "const char *tagp" 53.Ft long double 54.Fn nanl "const char *tagp" 55.Sh DESCRIPTION 56The call 57.Fn nan "\*qn-char-sequence\*q" 58is equivalent to the call 59.Fn strod "\*qNAN(n-char-sequence)\*q" "NULL" . 60The call 61.Fn nan "\*q\*q" 62is equivalent to the call 63.Fn strod "\*qNAN()\*q" "NULL" . 64.Pp 65The 66.Fn nanf 67and 68.Fn nanl 69functions are equivalent to 70.Fn nan 71but substituting 72.Fn strtof 73and 74.Fn strtod , 75respectively. 76.Sh RETURN VALUES 77.Ss IEEE 754 78The 79.Fn nan , 80.Fn nanf , 81and 82.Fn nanl 83functions return a quiet NaN as specified by 84.Fa tagp . 85.Ss VAX 86The 87.Fn nan , 88.Fn nanf , 89and 90.Fn nanl 91functions return zero. 92.Sh SEE ALSO 93.Xr math 3 , 94.Xr strod 3 95.Sh STANDARDS 96The 97.Fn nan , 98.Fn nanf , 99and 100.Fn nanl 101functions conform to 102.St -isoC-99 . 103