#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <sys/time.h>

void timer_handler(int signum)
{
    puts("handler");
}

int main()
{
    struct sigaction sa;
    struct itimerval timer;

    memset (&sa, 0x00, sizeof(sa));
    sa.sa_handler = &timer_handler;
    sigaction (SIGVTALRM, &sa, NULL);

    /* Set interval 1 sec */
    timer.it_value.tv_sec = 1;
    timer.it_value.tv_usec = 0;
    timer.it_interval.tv_sec = 1;
    timer.it_interval.tv_usec = 0;

    setitimer(ITIMER_VIRTUAL, &timer, NULL);

    for (;;) {
    }
}