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