Add a sleep function to dart:io

sdk/lib/io/process.dart

-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.io;
 
 // TODO(ager): The only reason for this class is that we
 // cannot patch a top-level at this point.
 class _ProcessUtils {
   external static _exit(int status);
   external static _setExitCode(int status);
+  external static _sleep(int status);
 }
 
 /**
  * Exit the Dart VM process immediately with the given [status] code.
  *
  * This does not wait for any asynchronous operations to terminate. Using
  * [exit] is therefore very likely to lose data.
  */
 void exit(int status) {
   if (status is !int) {
@@ skipping 10 matching lines @@
  * on normal termination.
  */
 set exitCode(int status) {
   if (status is !int) {
     throw new ArgumentError("setExitCode: int status expected");
   }
   _ProcessUtils._setExitCode(status);
 }
 
 /**
+ * Sleep for the duration specified in [duration].
+ *
+ * Use this with care, as no asynchronous operations can be processed
+ * in a isolate while it is blocked in a [sleep] call.
+ */
+void sleep(Duration duration) {
+  _ProcessUtils._sleep(duration.inMilliseconds);
+}
+
+/**
  * [Process] is used to start new processes using the static
  * [start] and [run] methods.
  */
 abstract class Process {
   /**
    * Starts a process running the [executable] with the specified
    * [arguments]. Returns a [:Future<Process>:] that completes with a
    * Process instance when the process has been successfully
    * started. That [Process] object can be used to interact with the
    * process. If the process cannot be started the returned [Future]
@@ skipping 207 matching lines @@
   /**
    * Contains the system message for the process exception if any.
    */
   final String message;
 
   /**
    * Contains the OS error code for the process exception if any.
    */
   final int errorCode;
 }