xref: /freebsd/lib/msun/man/copysign.3 (revision 123af6ec70016f5556da5972d4d63c7d175c06d3)
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31.Dd January 26, 2005
32.Dt COPYSIGN 3
33.Os
34.Sh NAME
35.Nm copysign ,
36.Nm copysignf ,
37.Nm copysignl
38.Nd copy sign
39.Sh LIBRARY
40.Lb libm
41.Sh SYNOPSIS
42.In math.h
43.Ft double
44.Fn copysign "double x" "double y"
45.Ft float
46.Fn copysignf "float x" "float y"
47.Ft long double
48.Fn copysignl "long double x" "long double y"
49.Sh DESCRIPTION
50The
51.Fn copysign ,
52.Fn copysignf
53and
54.Fn copysignl
55functions
56return
57.Fa x
58with its sign changed to
59.Fa y Ns 's .
60.Sh SEE ALSO
61.Xr fabs 3 ,
62.Xr fdim 3 ,
63.Xr ieee 3 ,
64.Xr math 3
65.Sh STANDARDS
66The
67.Fn copysign ,
68.Fn copysignf ,
69and
70.Fn copysignl
71routines conform to
72.St -isoC-99 .
73They implement the Copysign function recommended by
74.St -ieee754 .
75.Sh HISTORY
76The
77.Fn copysign ,
78.Fn copysignf ,
79and
80.Fn copysignl
81functions appeared in
82.Bx 4.3 ,
83.Fx 2.0 ,
84and
85.Fx 5.3 ,
86respectively.
87