xref: /netbsd/lib/libm/man/isinff.3 (revision bf9ec67e)
1.\"	$NetBSD: isinff.3,v 1.3 2002/02/07 07:00:49 ross Exp $
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34.\"     from: @(#)isinf.3	8.2 (Berkeley) 1/29/94
35.\"	from: NetBSD: isinf.3,v 1.5 1998/08/02 04:52:54 mycroft Exp
36.\"
37.Dd August 16, 1999
38.Dt ISINFF 3
39.Os
40.Sh NAME
41.Nm isinff ,
42.Nm isnanf
43.Nd test for infinity or not-a-number
44.Sh LIBRARY
45.Lb libm
46.Sh SYNOPSIS
47.Fd #include \*[Lt]math.h\*[Gt]
48.Ft int
49.Fn isinff float
50.Ft int
51.Fn isnanf float
52.Sh DESCRIPTION
53The
54.Fn isinff
55function
56returns 1 if the number is
57.Dq \\*(If ,
58otherwise 0.
59.Pp
60The
61.Fn isnanf
62function
63returns 1 if the number is
64.Dq not-a-number ,
65otherwise 0.
66.Sh SEE ALSO
67.Xr isinf 3 ,
68.Xr isnan 3 ,
69.Xr math 3
70.Rs
71.%T "IEEE Standard for Binary Floating-Point Arithmetic"
72.%Q ANSI
73.%R Std 754-1985
74.Re
75.Sh BUGS
76Neither the
77.Tn VAX
78nor the Tahoe floating point have distinguished values
79for either infinity or not-a-number.
80These routines always return 0 on those architectures.
81