xref: /netbsd/share/man/man9/mstohz.9 (revision bf9ec67e)
1.\"	$NetBSD: mstohz.9,v 1.2 2002/04/05 23:19:31 wiz Exp $
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3.\" Copyright (c) 2002 Manuel Bouyer.
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34.Dd April 4, 2002
35.Dt MSTOHZ 9
36.Os
37.Sh NAME
38.Nm mstohz
39.Nd convert milliseconds to system clock ticks
40.Sh SYNOPSIS
41.Fd #include \*[Lt]sys/param.h\*[Gt]
42.Ft int
43.Fn mstohz "int ms"
44.Sh DESCRIPTION
45.Nm
46can be used to convert time in milliseconds to system clock ticks, as used
47by the
48.Xr callout 9
49facility, in an integer-overflow safe way.
50.Pp
51This function is implemented as a define in the
52.Em \*[Lt]sys/param.h\*[Gt]
53header.  Individual ports can have a processor-specific, more efficient
54version implemented in their
55.Em \*[Lt]machine/param.h\*[Gt]
56header as a define.
57.Sh RETURN VALUES
58The return value is the number of clock ticks for the specified value.
59.Sh SEE ALSO
60.Xr callout 9
61.Sh BUGS
62The machine-independent
63.Fn
64function does not make use of expensive 64-bit integer arithmetic, so
65the result will be rounded down to one second if the parameter is larger
66than 131072 milliseconds.
67