Error checking for Stdio calls

runtime/bin/stdio.h

Index: runtime/bin/stdio.h
diff --git a/runtime/bin/stdio.h b/runtime/bin/stdio.h
index 9bf079a0dbd1c5324225f882850a795159fe0d15..56b591499b6e54cb825fe8809bf12a7e62d200af 100644
--- a/runtime/bin/stdio.h
+++ b/runtime/bin/stdio.h
@@ -19,13 +19,13 @@ namespace bin {
 
 class Stdin {
  public:
-  static int ReadByte();
+  static bool ReadByte(int* byte);
 
-  static bool GetEchoMode();
-  static void SetEchoMode(bool enabled);
+  static bool GetEchoMode(bool* enabled);
+  static bool SetEchoMode(bool enabled);
 
-  static bool GetLineMode();
-  static void SetLineMode(bool enabled);
+  static bool GetLineMode(bool* enabled);
+  static bool SetLineMode(bool enabled);
 
  private:
   DISALLOW_ALLOCATION();