1.\" Copyright (c) 1980, 1991, 1993, 1994 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)alarm.3 8.2 (Berkeley) 04/19/94 7.\" 8.Dd 9.Dt ALARM 3 10.Os BSD 4 11.Sh NAME 12.Nm alarm 13.Nd set signal timer alarm 14.Sh SYNOPSIS 15.Fd #include <unistd.h> 16.Ft u_int 17.Fn alarm "u_int seconds" 18.Sh DESCRIPTION 19.Bf -symbolic 20This interface is made obsolete by setitimer(2). 21.Ef 22.Pp 23The 24.Fn alarm 25function 26waits a count of 27.Ar seconds 28before asserting the terminating signal 29.Dv SIGALRM . 30When the signal has successfully been caught, 31.Fn alarm 32returns the amount of time left on the clock. 33The maximum number of 34.Ar seconds 35allowed 36is 2147483647. 37.Pp 38If an alarm has been set with 39.Fn alarm , 40another call to 41.Fn alarm 42will supersede the prior call. 43The request 44.Fn alarm "0" 45voids the current 46alarm. 47.Sh SEE ALSO 48.Xr sigaction 2 , 49.Xr setitimer 2 , 50.Xr sigpause 2 , 51.Xr sigvec 2 , 52.Xr signal 3 , 53.Xr sleep 3 , 54.Xr ualarm 3 , 55.Xr usleep 3 56.Sh HISTORY 57An 58.Fn alarm 59function appeared in 60.At v7 . 61