// --- public domain, no warranty.

#include <stdio.h>	// printf()
#include <stdlib.h>	// exit()
#include <string.h>	// memset()
#include <signal.h>	// sigaction()
#include <sys/time.h>	// setitimer()

#define	INTERVAL	10000		// usec

static	int	Counter = 0;

static	void	signal_handler(int num)
{
	Counter++;
	return;
}

int	main(int argc, char *argv[])
{
	struct	sigaction	act;
	struct	itimerval	itm;

	memset(&act, 0, sizeof(act));
	act.sa_handler = signal_handler;
	act.sa_flags = SA_RESTART;

	memset(&itm, 0, sizeof(itm));
	itm.it_interval.tv_usec = INTERVAL;
	itm.it_value.tv_usec = INTERVAL;

	if (sigaction(SIGALRM, &act, NULL) < 0) {
		printf("sigaction failed\n");
		exit(1);
	}

	if (setitimer(ITIMER_REAL, &itm, NULL) < 0) {
		printf("setitimer failed\n");
		exit(1);
	}

	while(1) {
		printf("%d\n", Counter / 100);
	}

	return 0;
}