timeout.9 revision 1.2
$OpenBSD: timeout.9,v 1.2 1999/09/02 17:28:07 espie Exp $
$NetBSD: timeout.9,v 1.7 1999/03/16 00:40:48 garbled Exp $
Copyright (c) 1996 The NetBSD Foundation, Inc.
All rights reserved.
This code is derived from software contributed to The NetBSD Foundation
by Paul Kranenburg.
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.
3. All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by the NetBSD
Foundation, Inc. and its contributors.
4. Neither the name of The NetBSD Foundation nor the names of its
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
``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 FOUNDATION OR CONTRIBUTORS
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.
.Dd June 23, 1996 .Dt TIMEOUT 9 .Os .Sh NAME .Nm timeout , .Nm untimeout .Nd execute a function after a specified length of time .Sh SYNOPSIS .Fd #include <sys/types.h> .Fd #include <sys/systm.h> .Ft void .Fn "timeout" "void (*ftn)(void *)" "void *arg" "int ticks" .Ft void .Fn "untimeout" "void (*ftn)(void *)" "void *arg" .Sh DESCRIPTION The function .Fn timeout schedules a call to the function given by the argument .Fa ftn 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 ftn should be a pointer to a function that takes a .Fa void * argument, to which the argument .Fa arg will be passed.
$NetBSD: timeout.9,v 1.7 1999/03/16 00:40:48 garbled Exp $
Copyright (c) 1996 The NetBSD Foundation, Inc.
All rights reserved.
This code is derived from software contributed to The NetBSD Foundation
by Paul Kranenburg.
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.
3. All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by the NetBSD
Foundation, Inc. and its contributors.
4. Neither the name of The NetBSD Foundation nor the names of its
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
``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 FOUNDATION OR CONTRIBUTORS
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.
.Dd June 23, 1996 .Dt TIMEOUT 9 .Os .Sh NAME .Nm timeout , .Nm untimeout .Nd execute a function after a specified length of time .Sh SYNOPSIS .Fd #include <sys/types.h> .Fd #include <sys/systm.h> .Ft void .Fn "timeout" "void (*ftn)(void *)" "void *arg" "int ticks" .Ft void .Fn "untimeout" "void (*ftn)(void *)" "void *arg" .Sh DESCRIPTION The function .Fn timeout schedules a call to the function given by the argument .Fa ftn 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 ftn should be a pointer to a function that takes a .Fa void * argument, to which the argument .Fa arg will be passed.
p The function .Fn untimeout cancels the first scheduled call
q i.e. the one with the shortest delay left that matches the .Aq Fa ftn , Ns Fa arg pair. If a match can not be found in the callout queue, nothing happens.
p The callout queue is statically sized, dependent on the .Va MAXUSERS parameter. .Sh CODE REFERENCES These functions are implemented in the file
a sys/kern/kern_clock.c . .Sh SEE ALSO .Xr hz 9 , .Xr sleep 9 .Sh BUGS .Fn untimeout should probably remove all matches from the queue.