#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <err.h>

int
main(int argc, char *argv[])
{
	int s;

	s = socket(AF_INET, SOCK_DGRAM, 0);
	if (s < 0)
		err(1, "socket");

	char buf[16] = "lo0";
	if (ioctl(s, SIOCGIFGROUP, buf) == -1)
		err(1, "ioctl");
	return 0;
}