Home | History | Annotate | Line # | Download | only in gen
alarm.c revision 1.8 
      1 /*	$NetBSD: alarm.c,v 1.8 1998/11/12 15:36:16 christos Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1983, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include <sys/cdefs.h>
     37 #if defined(LIBC_SCCS) && !defined(lint)
     38 #if 0
     39 static char sccsid[] = "@(#)alarm.c	8.1 (Berkeley) 6/4/93";
     40 #else
     41 __RCSID("$NetBSD: alarm.c,v 1.8 1998/11/12 15:36:16 christos Exp $");
     42 #endif
     43 #endif /* LIBC_SCCS and not lint */
     44 
     45 /*
     46  * Backwards compatible alarm.
     47  */
     48 #include "namespace.h"
     49 #include <sys/time.h>
     50 #include <unistd.h>
     51 
     52 #ifdef __weak_alias
     53 __weak_alias(alarm,_alarm);
     54 #endif
     55 
     56 unsigned int
     57 alarm(secs)
     58 	unsigned int secs;
     59 {
     60 	struct itimerval it, oitv;
     61 	struct itimerval *itp = &it;
     62 
     63 	timerclear(&itp->it_interval);
     64 	itp->it_value.tv_sec = secs;
     65 	itp->it_value.tv_usec = 0;
     66 	if (setitimer(ITIMER_REAL, itp, &oitv) == -1)
     67 		return (unsigned int) -1;
     68 	if (oitv.it_value.tv_usec)
     69 		oitv.it_value.tv_sec++;
     70 	return (unsigned int)oitv.it_value.tv_sec;
     71 }
     72