#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/time.h>
#include <errno.h>
#include <linux/input.h>

int main(int argc, char *argv[])
{
	struct input_event ev;
	double unow = 0, old_unow = 0;
	int fd;

	if (argc != 2) {
		printf("Usage: %s <inputdev>\n", argv[0]);
		return 1;
	}
	fd = open(argv[1], O_RDONLY);
	if (fd < 0) {
		printf("Cannot open %s.\n", argv[1]);
		return 2;
	}

	while (read(fd, &ev, sizeof(struct input_event)) ==
	       sizeof(struct input_event)) {
		if (ev.type != EV_SYN)
			continue;

		unow = ev.time.tv_sec + ev.time.tv_usec/1000000.0;
		if (unow - old_unow < 0.001) {
			struct timeval tm;

			gettimeofday(&tm, NULL);
			printf("[%5lu.%06lu] Premature timer expiry.\n",
			       tm.tv_sec, tm.tv_usec);
		}
		old_unow = unow;
	}

	return 0;
}