get interface type.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <netlink/route/link.h>

int main(int argc, char *argv[])
{
	struct rtnl_link *link;
	struct nl_sock *sk;
	int err;
	char *linkname;

	struct nl_dump_params params = {
		.dp_type = NL_DUMP_LINE,
		.dp_fd = stdout,
	};

	if (argc != 2) {
		printf ("Missing argument!\n");
		return 1;
	}
	linkname = argv[1];

	sk = nl_socket_alloc();
	if ((err = nl_connect(sk, NETLINK_ROUTE)) < 0) {
		nl_perror(err, "Unable to connect socket");
		return err;
	}
	struct nl_cache *link_cache;
	rtnl_link_alloc_cache(sk, AF_UNSPEC, &link_cache);

	link = rtnl_link_get_by_name(link_cache, linkname);
	if (!link) {
		printf("Error: No link with name %s\n", linkname);
		return 1;
	}

#if 0
	struct nl_addr *addr = rtnl_link_get_addr (link);
	char buf[256];
	printf ("Mac address is: %s\n", nl_addr2str (addr, buf, sizeof(buf)));
#endif

	nl_cache_dump_filter (link_cache, &params, OBJ_CAST(link));

	printf ("Type: %s\n", rtnl_link_get_type(link));

	rtnl_link_put(link);
	nl_close(sk);

	return 0;
}