/*
 * Copyright (c) 1985 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that: (1) source distributions retain this entire copyright
 * notice and comment, and (2) distributions including binaries display
 * the following acknowledgement:  ``This product includes software
 * developed by the University of California, Berkeley and its contributors''
 * in the documentation or other materials provided with the distribution
 * and in all advertising materials mentioning features or use of this
 * software. Neither the name of the University nor the names of its
 * contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#if !defined(lint) && !defined(SABER)
static char *sccsid = "@(#)ualarm.c  5.4 (Berkeley) 6/1/90";
#endif

#include <sys/time.h>

#define	USPS	1000000		/* # of microseconds in a second */

/*
 * Generate a SIGALRM signal in ``usecs'' microseconds.
 * If ``reload'' is non-zero, keep generating SIGALRM
 * every ``reload'' microseconds after the first signal.
 */
unsigned
ualarm(usecs, reload)
	register unsigned usecs;
	register unsigned reload;
{
	struct itimerval new, old;

	new.it_interval.tv_usec = reload % USPS;
	new.it_interval.tv_sec = reload / USPS;
	
	new.it_value.tv_usec = usecs % USPS;
	new.it_value.tv_sec = usecs / USPS;

	if (setitimer(ITIMER_REAL, &new, &old) == 0)
		return (old.it_value.tv_sec * USPS + old.it_value.tv_usec);
	/* else */
		return (-1);
}

