#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <ifaddrs.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int
main(int argc, char *argv[])
{
	struct ifaddrs *ifaddr, *ifa;
	int family, s;
	char host[NI_MAXHOST];

	if (getifaddrs(&ifaddr) == -1) {
		perror("getifaddrs");
		exit(EXIT_FAILURE);
	}

	/*
	 * Walk through linked list, maintaining head pointer so we
	 * can free list later
	 */
	for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
		family = ifa->ifa_addr->sa_family;

		/*
		 * Display interface name and family (including symbolic
		 * form of the latter for the common families)
		 */
		printf("%s  address family: %d%s\n",
		    ifa->ifa_name, family,
		    (family == AF_INET) ?   " (AF_INET)" :
		    (family == AF_INET6) ?  " (AF_INET6)" : "");

		/*
		 * For an AF_INET* interface address, display the address
		 */
		if (family == AF_INET || family == AF_INET6) {
			s = getnameinfo(ifa->ifa_addr,
			    (family == AF_INET) ? sizeof(struct sockaddr_in) :
			    sizeof(struct sockaddr_in6),
			    host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
			if (s != 0) {
				printf("getnameinfo() failed: %s\n",
				    gai_strerror(s));
				exit(EXIT_FAILURE);
			}
			printf("\taddress: <%s>\n", host);
		}
	}

	freeifaddrs(ifaddr);
	exit(EXIT_SUCCESS);
}