mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-20 11:11:24 +00:00
95 lines
2.8 KiB
Groff
95 lines
2.8 KiB
Groff
.\" Copyright (c) 1980, 1991, 1993, 1994
|
|
.\" The Regents of the University of California. 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.
|
|
.\" 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
|
|
.\"
|
|
.\" @(#)alarm.3 8.2 (Berkeley) 4/19/94
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd April 19, 1994
|
|
.Dt ALARM 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm alarm
|
|
.Nd set signal timer alarm
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In unistd.h
|
|
.Ft unsigned int
|
|
.Fn alarm "unsigned int seconds"
|
|
.Sh DESCRIPTION
|
|
.Bf -symbolic
|
|
This interface is made obsolete by
|
|
.Xr setitimer 2 .
|
|
.Ef
|
|
.Pp
|
|
The
|
|
.Fn alarm
|
|
function sets a timer to deliver the signal
|
|
.Dv SIGALRM
|
|
to the calling process after the specified number of
|
|
.Fa seconds .
|
|
If an alarm has already been set with
|
|
.Fn alarm
|
|
but has not been delivered, another call to
|
|
.Fn alarm
|
|
will supersede the prior call.
|
|
The request
|
|
.Fn alarm "0"
|
|
voids the current
|
|
alarm and the signal SIGALRM will not be delivered.
|
|
.Pp
|
|
Due to
|
|
.Xr setitimer 2
|
|
restriction the maximum number of
|
|
.Fa seconds
|
|
allowed is 100000000.
|
|
.Sh RETURN VALUES
|
|
The return value of
|
|
.Fn alarm
|
|
is the amount of time left on the timer from a previous call to
|
|
.Fn alarm .
|
|
If no alarm is currently set, the return value is 0.
|
|
.Sh SEE ALSO
|
|
.Xr setitimer 2 ,
|
|
.Xr sigaction 2 ,
|
|
.Xr sigpause 2 ,
|
|
.Xr sigvec 2 ,
|
|
.Xr signal 3 ,
|
|
.Xr sleep 3 ,
|
|
.Xr ualarm 3 ,
|
|
.Xr usleep 3
|
|
.\" .Sh STANDARDS
|
|
.\" The
|
|
.\" .Fn alarm
|
|
.\" function conforms to
|
|
.\" .St -p1003.1-90 .
|
|
.Sh HISTORY
|
|
An
|
|
.Fn alarm
|
|
function appeared in
|
|
.At v7 .
|