timeout.9 revision 24022
Copyright (c) 1996 Joerg Wunsch
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
$Id: timeout.9,v 1.3 1997/02/22 13:26:29 peter Exp $
"
.Dd April 13, 1996 .Os .Dt TIMEOUT 9 .Sh NAME .Nm timeout , .Nm untimeout .Nd schedule timer events .Sh SYNOPSIS .Fd #include <sys/param.h> .Fd #include <sys/systm.h> .Ft typedef void timeout_t \*(lpvoid *\*(rp; .Ft void .Fn timeout "timeout_t *func" "void *arg" "int ticks" .Ft void .Fn untimeout "timeout_t *func" "void *arg" .Sh DESCRIPTION The .Nm timeout facility allows the execution of a function after a specified amount of time. The function .Ar func is being called with the opaque argument .Ar arg after .Ar ticks timer ticks have been elapsed. It's often convenient to use the external variable .Dv hz to compute the amount of .Ar ticks to wait.
Copyright (c) 1996 Joerg Wunsch
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
$Id: timeout.9,v 1.3 1997/02/22 13:26:29 peter Exp $
"
.Dd April 13, 1996 .Os .Dt TIMEOUT 9 .Sh NAME .Nm timeout , .Nm untimeout .Nd schedule timer events .Sh SYNOPSIS .Fd #include <sys/param.h> .Fd #include <sys/systm.h> .Ft typedef void timeout_t \*(lpvoid *\*(rp; .Ft void .Fn timeout "timeout_t *func" "void *arg" "int ticks" .Ft void .Fn untimeout "timeout_t *func" "void *arg" .Sh DESCRIPTION The .Nm timeout facility allows the execution of a function after a specified amount of time. The function .Ar func is being called with the opaque argument .Ar arg after .Ar ticks timer ticks have been elapsed. It's often convenient to use the external variable .Dv hz to compute the amount of .Ar ticks to wait.
p If the timeout event should be removed before the timer expires, .Nm untimeout must be called with the exact .Ar func and .Ar arg arguments as the corresponding call to .Fn timeout .
p Unlike the functions of .Xr sleep 9 , .Fn timeout and .Fn untimeout can be called from within an interrupt context. .Sh SEE ALSO .Xr sleep 9 .Sh HISTORY The .Nm timeout facility is very old. .Sh BUGS Since the timer queue is sorted and uses time differences rather than absolute times, inserting and removing timer events can be costly if it is done too frequently. .Sh AUTHORS This man page has been written by