Add a small example.

lib/libc/net/getifaddrs.3

@@ -1,4 +1,4 @@
-.\"	$NetBSD: getifaddrs.3,v 1.12 2010/03/22 19:30:54 joerg Exp $
+.\"	$NetBSD: getifaddrs.3,v 1.13 2013/04/07 22:54:26 christos Exp $
 .\"	BSDI	getifaddrs.3,v 2.5 2000/02/23 14:51:59 dab Exp
 .\"
 .\" Copyright (c) 1995, 1999
@@ -21,7 +21,7 @@
 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
-.Dd April 21, 2009
+.Dd April 7, 2013
 .Dt GETIFADDRS 3
 .Os
 .Sh NAME
@@ -133,6 +133,36 @@ Upon successful completion, a value of 0 is returned.
 Otherwise, a value of -1 is returned and
 .Va errno
 is set to indicate the error.
+.Sh EXAMPLES            
+The following example program prints a list of all addresses configured
+on the system.
+.Bd -literal -offset indent
+#include \*[Lt]sys/types.h\*[Gt]
+#include \*[Lt]sys/socket.h\*[Gt]
+#include \*[Lt]stdio.h\*[Gt]
+#include \*[Lt]ifaddrs.h\*[Gt]
+#include \*[Lt]util.h\*[Gt]
+#include \*[Lt]err.h\*[Gt]
+#include \*[Lt]stdlib.h\*[Gt]
+
+int
+main(int argc, char *argv[])
+{
+	struct ifaddrs *ifa, *a;
+
+	if (getifaddrs(\*[Am]ifa) == -1)
+		err(EXIT_FAILURE, "getifaddrs");
+
+	for (a = ifa; a; a = a->ifa_next) {
+		char buf[1024];
+		sockaddr_snprintf(buf, sizeof(buf), "%f %a",
+		    a->ifa_addr);
+		printf("%s %x %s\\n", a->ifa_name, a->ifa_flags, buf);
+	}
+	freeifaddrs(ifa);
+	return EXIT_SUCCESS;
+}
+.Ed
 .Sh ERRORS
 The
 .Fn getifaddrs