NetBSD/share/man/man9/mstohz.9

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.Dd April 4, 2002
.Dt MSTOHZ 9
.Os
.Sh NAME
.Nm mstohz
.Nd convert milliseconds to system clock ticks
.Sh SYNOPSIS
.In sys/param.h
.Ft int
.Fn mstohz "int ms"
.Sh DESCRIPTION
.Nm
can be used to convert time in milliseconds to system clock ticks, as used
by the
.Xr callout 9
facility, in an integer-overflow safe way.
.Pp
This function is implemented as a define in the
.Em \*[Lt]sys/param.h\*[Gt]
header.
Individual ports can have a processor-specific, more efficient
version implemented in their
.Em \*[Lt]machine/param.h\*[Gt]
header as a define.
.Sh RETURN VALUES
The return value is the number of clock ticks for the specified value.
.Sh SEE ALSO
.Xr callout 9
.Sh BUGS
The machine-independent
.Fn mstohz
function does not make use of expensive 64-bit integer arithmetic, so
the result will be rounded down to one second if the parameter is larger
than 131072 milliseconds.