nl-link-ifindex2name.c

/*
 * src/nl-link-ifindex2name.c     Transform a interface index to its name
 *
 *      This library is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU Lesser General Public
 *      License as published by the Free Software Foundation version 2.1
 *      of the License.
 *
 * Copyright (c) 2003-2009 Thomas Graf <tgraf@suug.ch>
 */

#include <netlink/cli/utils.h>
#include <netlink/cli/link.h>

static void print_usage(void)
{
        printf("Usage: nl-link-ifindex2name <ifindex>\n");
        exit(0);
}

int main(int argc, char *argv[])
{
        struct nl_sock *sock;
        struct nl_cache *link_cache;
        char name[IFNAMSIZ];
        uint32_t ifindex;

        if (argc < 2)
                print_usage();

        sock = nl_cli_alloc_socket();
        nl_cli_connect(sock, NETLINK_ROUTE);
        link_cache = nl_cli_link_alloc_cache(sock);

        ifindex = nl_cli_parse_u32(argv[1]);

        if (!rtnl_link_i2name(link_cache, ifindex, name, sizeof(name)))
                nl_cli_fatal(ENOENT, "Interface index %d does not exist",
                             ifindex);

        printf("%s\n", name);

        return 0;
}