NetBSD/lib/libc/gen/alarm.3

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.\" Copyright (c) 1980, 1991 Regents of the University of California.
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.\" from: @(#)alarm.3 6.4 (Berkeley) 4/19/91
.\" $Id: alarm.3,v 1.7 1994/01/28 20:14:54 jtc Exp $
.\"
.Dd April 19, 1991
.Dt ALARM 3
.Os BSD 4
.Sh NAME
.Nm alarm
.Nd set signal timer alarm
.Sh SYNOPSIS
.Fd #include <unistd.h>
.Ft unsigned int
.Fn alarm "unsigned int seconds"
.Sh DESCRIPTION
.Bf -symbolic
This interface is made obsolete by setitimer(2).
.Ef
.Pp
The
.Fn alarm
function
waits a count of
.Ar seconds
before asserting the terminating signal
.Dv SIGALRM .
When the signal has successfully been caught,
.Fn alarm
returns the amount of time left on the clock.
The maximum number of
.Ar seconds
allowed
is 2147483647.
.Pp
If an alarm has been set with
.Fn alarm ,
another call to
.Fn alarm
will supersede the prior call.
The request
.Fn alarm "0"
voids the current
alarm.
.Sh SEE ALSO
.Xr sigaction 2 ,
.Xr setitimer 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 .