xref: /freebsd/share/man/man3/Q_FRAWMASK.3 (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
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26.Dd July 8, 2018
27.Dt Q_FRAWMASK 3
28.Os
29.Sh NAME
30.Nm Q_FRAWMASK ,
31.Nm Q_GFRAW ,
32.Nm Q_GFABSVAL ,
33.Nm Q_GFVAL ,
34.Nm Q_SFVAL
35.Nd fixed-point math functions which manipulate the fractional data bits
36.Sh SYNOPSIS
37.In sys/qmath.h
38.Ft ITYPE
39.Fn Q_FRAWMASK "QTYPE q"
40.Ft ITYPE
41.Fn Q_GFRAW "QTYPE q"
42.Ft ITYPE
43.Fn Q_GFABSVAL "QTYPE q"
44.Ft ITYPE
45.Fn Q_GFVAL "QTYPE q"
46.Ft QTYPE
47.Fn Q_SFVAL "QTYPE q" "ITYPE fv"
48.Sh DESCRIPTION
49.Fn Q_FRAWMASK
50returns a
51.Fa q Ns -specific
52bit mask for
53.Fa q Ap s
54fractional data bits.
55.Pp
56.Fn Q_GFRAW
57returns
58.Fa q Ap s
59raw masked fractional data bits.
60.Pp
61.Fn Q_GFABSVAL
62and
63.Fn Q_GFVAL
64return the absolute and real values of
65.Fa q Ap s
66fractional data bits respectively.
67.Pp
68.Fn Q_SFVAL
69sets
70.Fa q Ap s
71fractional data bits to the value
72.Fa fv .
73.Pp
74All of those functions operate on
75the following data types:
76.Vt s8q_t ,
77.Vt u8q_t ,
78.Vt s16q_t ,
79.Vt u16q_t ,
80.Vt s32q_t ,
81.Vt u32q_t ,
82.Vt s64q_t ,
83and
84.Vt u64q_t ,
85which are referred to generically as
86.Fa QTYPE .
87The
88.Fa ITYPE
89refers to the
90.Xr stdint 7
91integer types.
92.Pp
93For more details, see
94.Xr qmath 3 .
95.Sh RETURN VALUES
96.Fn Q_FRAWMASK ,
97.Fn Q_GFRAW ,
98.Fn Q_GFABSVAL
99and
100.Fn Q_GFVAL
101return their respective values as integers of the same underlying ITYPE as
102.Fa q .
103.Pp
104.Fn Q_SFVAL
105returns the value of
106.Fa q
107post set.
108.Sh SEE ALSO
109.Xr errno 2 ,
110.Xr qmath 3 ,
111.Xr stdint 7
112.Sh HISTORY
113The
114.Xr qmath 3
115functions first appeared in
116.Fx 13.0 .
117.Sh AUTHORS
118.An -nosplit
119The
120.Xr qmath 3
121functions and this manual page were written by
122.An Lawrence Stewart Aq Mt lstewart@FreeBSD.org
123and sponsored by Netflix, Inc.
124