#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>

int main(void)
{
    int ret = 0;
    int fd = open("/dev/watchdog", O_WRONLY);

    if (fd == -1) {
        perror("watchdog");
        return -1;
    }
    while (1) {
        ret = write(fd, "\0", 1);
        if (ret != 1) {
            break;
        }
        sleep(10);
    }
    close(fd);
    return -1;
}