1.\" $NetBSD: alarm.3,v 1.9 1995/02/25 15:39:01 cgd Exp $ 2.\" 3.\" Copyright (c) 1980, 1991, 1993, 1994 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)alarm.3 8.2 (Berkeley) 4/19/94 35.\" 36.Dd April 19, 1994 37.Dt ALARM 3 38.Os BSD 4 39.Sh NAME 40.Nm alarm 41.Nd set signal timer alarm 42.Sh SYNOPSIS 43.Fd #include <unistd.h> 44.Ft unsigned int 45.Fn alarm "unsigned int seconds" 46.Sh DESCRIPTION 47.Bf -symbolic 48This interface is made obsolete by setitimer(2). 49.Ef 50.Pp 51The 52.Fn alarm 53function 54waits a count of 55.Ar seconds 56before asserting the terminating signal 57.Dv SIGALRM . 58When the signal has successfully been caught, 59.Fn alarm 60returns the amount of time left on the clock. 61The maximum number of 62.Ar seconds 63allowed 64is 2147483647. 65.Pp 66If an alarm has been set with 67.Fn alarm , 68another call to 69.Fn alarm 70will supersede the prior call. 71The request 72.Fn alarm "0" 73voids the current 74alarm. 75.Sh SEE ALSO 76.Xr sigaction 2 , 77.Xr setitimer 2 , 78.Xr sigpause 2 , 79.Xr sigvec 3 , 80.Xr signal 3 , 81.Xr sleep 3 , 82.Xr ualarm 3 , 83.Xr usleep 3 84.Sh STANDARDS 85The 86.Fn alarm 87function conforms to 88.St -p1003.1-90 . 89.Sh HISTORY 90An 91.Fn alarm 92function appeared in 93.At v7 . 94