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--- exceptions version 4	Sun Nov 13 08:24:38 -0800 2011
+++ exceptions version 5	Tue Feb 21 10:10:03 -0800 2012
@@ -1,32 +1,32 @@
 Exception
  NoMemoryError
  ScriptError
    LoadError
    NotImplementedError
    SyntaxError
  SignalException
    Interrupt
      Timeout::Error    # require 'timeout' for Timeout::Error
  StandardError         # caught by rescue if no type is specified
    ArgumentError
    IOError
      EOFError
    IndexError
    LocalJumpError
    NameError
      NoMethodError
    RangeError
      FloatDomainError
    RegexpError
    RuntimeError
      Timeout::Error    # moved here in ruby 1.9.2
    SecurityError
    SocketError
-   SystemCallError
+   SystemCallError     # Errno::* inherits here
    SystemStackError
    ThreadError
    TypeError
    ZeroDivisionError
  SystemExit
  fatal