xref: /minix3/lib/libc/gen/isnormal.3 (revision 2fe8fb192fe7e8720e3e7a77f928da545e872a6a)
1.\"	$NetBSD: isnormal.3,v 1.3 2008/04/30 13:10:50 martin Exp $
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3.\" Copyright (c) 2003 The NetBSD Foundation, Inc.
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6.\" This code is derived from software contributed to The NetBSD Foundation
7.\" by Klaus Klein.
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30.Dd October 29, 2003
31.Dt ISNORMAL 3
32.Os
33.Sh NAME
34.Nm isnormal
35.Nd test for normal value
36.Sh LIBRARY
37.Lb libc
38.Sh SYNOPSIS
39.In math.h
40.Ft int
41.Fn isnormal "real-floating x"
42.Sh DESCRIPTION
43The
44.Fn isnormal
45macro determines whether its argument
46.Fa x
47has a normal 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 normal, and neither zero, subnormal, infinite nor NaN.
55.Ss VAX
56It is determined whether the value of
57.Fa x
58is finite, and neither true zero, dirty zero nor ROP.
59.Sh RETURN VALUES
60The
61.Fn isnormal
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 fpclassify 3 ,
70.Xr isfinite 3 ,
71.Xr math 3 ,
72.Xr signbit 3
73.Sh STANDARDS
74The
75.Fn isnormal
76macro conforms to
77.St -isoC-99 .
78