1/*
2 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
3 * Use is subject to license terms.
4 */
5
6/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
7/*	  All Rights Reserved  	*/
8
9/*
10 * Copyright (c) 1985 Regents of the University of California.
11 * All rights reserved.  The Berkeley software License Agreement
12 * specifies the terms and conditions for redistribution.
13 */
14
15#pragma ident	"%Z%%M%	%I%	%E% SMI"
16
17#include "lint.h"
18#include <sys/types.h>
19#include <sys/time.h>
20#include <unistd.h>
21
22#define	USPS	1000000		/* # of microseconds in a second */
23
24/*
25 * Generate a SIGALRM signal in ``usecs'' microseconds.
26 * If ``reload'' is non-zero, keep generating SIGALRM
27 * every ``reload'' microseconds after the first signal.
28 */
29useconds_t
30ualarm(useconds_t usecs, useconds_t reload)
31{
32	struct itimerval new, old;
33
34	new.it_interval.tv_usec = reload % USPS;
35	new.it_interval.tv_sec = reload / USPS;
36
37	new.it_value.tv_usec = usecs % USPS;
38	new.it_value.tv_sec = usecs / USPS;
39
40	if (setitimer(ITIMER_REAL, &new, &old) != 0)
41		return (0);	/* no errors are defined */
42	return (old.it_value.tv_sec * USPS + old.it_value.tv_usec);
43}
44