Enable using the service library from dart:io applications.

runtime/bin/vmservice/client/bin/shell.dart

Index: runtime/bin/vmservice/client/bin/shell.dart
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--- runtime/bin/vmservice/client/bin/shell.dart	(revision 0)
+++ runtime/bin/vmservice/client/bin/shell.dart	(revision 0)
@@ -0,0 +1,35 @@
+// Copyright (c) 2014, 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.
+
+library shell;
+
+import 'package:observatory/service_io.dart';
+
+import 'dart:io';
+
+// Simple demo for service_io library. Connects to localhost on the default
+// port, picks the first isolate, reads requests from stdin, and prints
+// results to stdout. Example session:
+// <<< prefix /isolates/1071334835
+// >>> /classes/40
+// <<< {"type":"Class","id":"classes\/40","name":"num","user_name":"num",...
+// >>> /objects/0
+// >>> {"type":"Array","class":{"type":"@Class","id":"classes\/62",...
+
+void repl(VM vm, String prefix, String lastResult) {
+  print(lastResult);
+  // TODO(koda): Use 'get' when ServiceObjects have more informative toString.
+  vm.getString(prefix + stdin.readLineSync()).then((String result) {
+    repl(vm, prefix, result);
+  });
+}
+
+void main() {
+  String addr = 'ws://localhost:8181/ws';
+  new WebSocketVM(new WebSocketVMTarget(addr)).get('vm').then((VM vm) {
+    Isolate isolate = vm.isolates.first;
+    String prefix = '${isolate.link}';
+    repl(vm, prefix, 'prefix $prefix');
+  });
+}