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 #include "lint.h"
16 #include <sys/types.h>
17 #include <sys/time.h>
18 #include <unistd.h>
19
20 #define USPS 1000000 /* # of microseconds in a second */
21
22 /*
23 * Generate a SIGALRM signal in ``usecs'' microseconds.
24 * If ``reload'' is non-zero, keep generating SIGALRM
25 * every ``reload'' microseconds after the first signal.
26 */
27 useconds_t
ualarm(useconds_t usecs,useconds_t reload)28 ualarm(useconds_t usecs, useconds_t reload)
29 {
30 struct itimerval new, old;
31
32 new.it_interval.tv_usec = reload % USPS;
33 new.it_interval.tv_sec = reload / USPS;
34
35 new.it_value.tv_usec = usecs % USPS;
36 new.it_value.tv_sec = usecs / USPS;
37
38 if (setitimer(ITIMER_REAL, &new, &old) != 0)
39 return (0); /* no errors are defined */
40 return (old.it_value.tv_sec * USPS + old.it_value.tv_usec);
41 }
42