NetBSD/share/man/man9/timeout.9

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.\" $NetBSD: timeout.9,v 1.5 1998/06/08 11:33:21 lukem Exp $
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.\" Copyright (c) 1996 The NetBSD Foundation, Inc.
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.Dd June 23, 1996
.Dt TIMEOUT 9
.Os NetBSD
.Sh NAME
.Nm timeout ,
.Nm untimeout
.Nd execute a function after a specified length of time
.Sh SYNOPSIS
.Ft void
.Fn "timeout" "void (*fnt)(void *)" "void *arg" "int ticks"
.Ft void
.Fn "untimeout" "void (*fnt)(void *)" "void *arg"
.Sh DESCRIPTION
The function
.Fn timeout
schedules a call to the function given by the argument
.Fa fnt
to take place after
.Fa ticks Ns No /hz
seconds. Non-positive values of
.Fa ticks
are silently converted to the value
.Sq 1 .
.Fa fnt
should be a pointer to a function that takes a
.Fa void *
argument, in which the
.Fn timeout
argument
.Fa arg
will be passed.
.Pp
The function
.Fn untimeout
cancels the first scheduled call
.Pq i.e. the one with the shortest delay left
that matches the
.Aq Fa fnt , Ns Fa arg
pair. If a match can not be found in the callout queue, nothing happens.
.Sh SEE ALSO
.Xr hz 9
.Sh BUGS
.Fn untimeout
should probably remove all matches from the queue.