README in pdf-reader-0.5 vs README in pdf-reader-0.5.1

@@ -24,11 +24,12 @@
 images, shapes, etc) it will call methods on the receiver class.  What those
 methods do is entirely up to you - save the text, extract images, count pages,
 read metadata, whatever.
 
 For a full list of the supported callback methods and a description of when they
-will be called, refer to PDF::Reader::Content.
+will be called, refer to PDF::Reader::Content. See the code examples below for a
+way to print a list of all the callbacks generated by a file to STDOUT.
 
 = Exceptions
 
 There are two key exceptions that you will need to watch out for when processing a 
 PDF file:
@@ -70,10 +71,24 @@
     end
   end
 
   receiver = PageReceiver.new
   pdf = PDF::Reader.file("somefile.pdf", receiver)
-  puts "#{pdf.page_count} pages"
+  puts "#{receiver.page_count} pages"
+
+== List all callbacks generated by a single PDF
+
+WARNING: this will generate a *lot* of output, so you probably want to pipe
+it through less or to a text file.
+  
+  require 'rubygems'
+  require 'pdf/reader'
+
+  receiver = PDF::Reader::RegisterReceiver.new
+  pdf = PDF::Reader.file("somefile.pdf", receiver)
+  receiver.callbacks.each do |cb|
+    puts cb
+  end
 
 == Basic RSpec of a generated PDF 
 
   require 'rubygems'
   require 'pdf/reader'