1.\" $NetBSD: isfinite.3,v 1.4 2011/08/06 11:02:41 jruoho Exp $ 2.\" 3.\" Copyright (c) 2003 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.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd August 6, 2011 31.Dt ISFINITE 3 32.Os 33.Sh NAME 34.Nm isfinite 35.Nd test for finite value 36.Sh LIBRARY 37.Lb libc 38.Sh SYNOPSIS 39.In math.h 40.Ft int 41.Fn isfinite "real-floating x" 42.Sh DESCRIPTION 43The 44.Fn isfinite 45determines whether its argument 46.Fa x 47has a finite value. 48An argument represented in a format wider than its semantic type is 49converted to its semantic type first. 50The determination is then based on the type of the argument. 51.Ss IEEE 754 52It is determined whether the value of 53.Fa x 54is zero, subnormal, or normal, and neither infinite nor NaN. 55.Ss VAX 56It is determined whether the value of 57.Fa x 58is true zero or finite, and neither dirty zero nor ROP. 59.Sh RETURN VALUES 60The 61.Fn isfinite 62macro returns a non-zero value if the value of 63.Fa x 64is finite. 65Otherwise 0 is returned. 66.Sh ERRORS 67No errors are defined. 68.Sh SEE ALSO 69.Xr finite 3 , 70.Xr fpclassify 3 , 71.Xr isnormal 3 , 72.Xr math 3 , 73.Xr signbit 3 74.Sh STANDARDS 75The 76.Fn isfinite 77macro conforms to 78.St -isoC-99 . 79