Improve documentation on address for socket bind

sdk/lib/io/socket.dart

Index: sdk/lib/io/socket.dart
diff --git a/sdk/lib/io/socket.dart b/sdk/lib/io/socket.dart
index 48c864064f295f6c3bd1cb12ba3b6f322a3c8be8..c5eb054109a2b59d1b5934847f4952608748e944 100644
--- a/sdk/lib/io/socket.dart
+++ b/sdk/lib/io/socket.dart
@@ -16,12 +16,20 @@ abstract class RawServerSocket implements Stream<RawSocket> {
    * completes the server socket is bound to the given [address] and
    * [port] and has started listening on it.
    *
+   * The default value for [address] is 127.0.0.1, which will allow
+   * only incoming connections from the local host. To allow for
+   * incoming connection from the network use either the value 0.0.0.0
+   * to bind to all interfaces or the IP address of a specific
+   * interface.
+   *
    * If [port] has the value [:0:] (the default) an ephemeral port will
    * be chosen by the system. The actual port used can be retrieved
    * using the [:port:] getter.
    *
-   * If [backlog] has the value of [:0:] a reasonable value will be
-   * chosen by the system.
+   * The optional argument [backlog] can be used to specify the listen
+   * backlog for the underlying OS listen setup. If [backlog] has the
+   * value of [:0:] (the default) a reasonable value will be chosen by
+   * the system.
    */
   external static Future<RawServerSocket> bind([String address = "127.0.0.1",
                                                int port = 0,
@@ -51,12 +59,20 @@ abstract class ServerSocket implements Stream<Socket> {
    * completes the server socket is bound to the given [address] and
    * [port] and has started listening on it.
    *
+   * The default value for [address] is 127.0.0.1, which will allow
+   * only incoming connections from the local host. To allow for
+   * incoming connection from the network use either the value 0.0.0.0
+   * to bind to all interfaces or the IP address of a specific
+   * interface.
+   *
    * If [port] has the value [:0:] (the default) an ephemeral port will
    * be chosen by the system. The actual port used can be retrieved
    * using the [port] getter.
    *
-   * If [backlog] has the value of [:0:] a reasonable value will be
-   * chosen by the system.
+   * The optional argument [backlog] can be used to specify the listen
+   * backlog for the underlying OS listen setup. If [backlog] has the
+   * value of [:0:] (the default) a reasonable value will be chosen by
+   * the system.
    */
   external static Future<ServerSocket> bind([String address = "127.0.0.1",
                                              int port = 0,