diff -r 713db33a4ebc Lib/idlelib/OutputWindow.py
--- a/Lib/idlelib/OutputWindow.py	Sat Mar 10 23:43:12 2012 +0100
+++ b/Lib/idlelib/OutputWindow.py	Sun Mar 11 21:10:28 2012 -0500
@@ -40,6 +40,7 @@
         self.text.insert(mark, s, tags)
         self.text.see(mark)
         self.text.update()
+        return len(s)
 
     def writelines(self, lines):
         for line in lines:
diff -r 713db33a4ebc Lib/idlelib/PyShell.py
--- a/Lib/idlelib/PyShell.py	Sat Mar 10 23:43:12 2012 +0100
+++ b/Lib/idlelib/PyShell.py	Sun Mar 11 21:10:28 2012 -0500
@@ -755,7 +755,7 @@
 
     def write(self, s):
         "Override base class method"
-        self.tkconsole.stderr.write(s)
+        return self.tkconsole.stderr.write(s)
 
     def display_port_binding_error(self):
         tkMessageBox.showerror(
@@ -1223,7 +1223,7 @@
     def write(self, s, tags=()):
         try:
             self.text.mark_gravity("iomark", "right")
-            OutputWindow.write(self, s, tags, "iomark")
+            count = OutputWindow.write(self, s, tags, "iomark")
             self.text.mark_gravity("iomark", "left")
         except:
             raise ###pass  # ### 11Aug07 KBK if we are expecting exceptions
@@ -1232,6 +1232,7 @@
             self.canceled = 0
             if not use_subprocess:
                 raise KeyboardInterrupt
+        return count
 
 class PseudoFile(object):
 
@@ -1241,7 +1242,7 @@
         self.encoding = encoding
 
     def write(self, s):
-        self.shell.write(s, self.tags)
+        return self.shell.write(s, self.tags)
 
     def writelines(self, lines):
         for line in lines: