From 4f775ac5caa35f824b0bcacafa010f6e0709c62d Mon Sep 17 00:00:00 2001
From: Patrick Mahoney <pat@polycrystal.org>
Date: Mon, 12 Dec 2011 20:51:06 -0600
Subject: [PATCH] Add backwards compatibility define_singleton_method for Ruby
 1.8.

---
 lib/process_shared.rb                         | 19 +++++++++++++++++++
 lib/process_shared/define_singleton_method.rb | 14 ++++++++++++++
 spec/spec_helper.rb                           |  3 +++
 3 files changed, 36 insertions(+)
 create mode 100644 lib/process_shared/define_singleton_method.rb

diff --git a/lib/process_shared.rb b/lib/process_shared.rb
index 717d0ee..6b1e8bb 100644
--- a/lib/process_shared.rb
+++ b/lib/process_shared.rb
@@ -1,6 +1,25 @@
 require 'ffi'
 
+if VERSION =~ /^1.8/
+  require 'process_shared/define_singleton_method'
+  
+  module ProcessShared
+    module PSem
+      extend DefineSingletonMethod
+    end
+
+    module RT
+      extend DefineSingletonMethod
+    end
+
+    module LibC
+      extend DefineSingletonMethod
+    end
+  end
+end
+
 require 'process_shared/semaphore'
 require 'process_shared/bounded_semaphore'
 require 'process_shared/mutex'
 require 'process_shared/shared_memory'
+
diff --git a/lib/process_shared/define_singleton_method.rb b/lib/process_shared/define_singleton_method.rb
new file mode 100644
index 0000000..dd45966
--- /dev/null
+++ b/lib/process_shared/define_singleton_method.rb
@@ -0,0 +1,14 @@
+module ProcessShared
+  module DefineSingletonMethod
+    # This method was added in Ruby 1.9.x.  Include this module for
+    # backwards compatibility.
+    #
+    # This isn't exactly compatible with the method in 1.9 which can
+    # take a Proc, Method, or a block.  This only accepts a block.
+    def define_singleton_method(sym, &block)
+      eigenclass = class << self; self; end
+      eigenclass.send(:define_method, sym, &block)
+    end
+  end
+end
+
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index b415a70..7ae810f 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,8 +1,11 @@
+require 'rubygems' if VERSION =~ /^1.8/
 gem 'minitest'
 require 'minitest/spec'
 require 'minitest/autorun'
 require 'minitest/matchers'
 
+require 'process_shared'
+
 class RangeMatcher
   def initialize(operator, limit)
     @operator = operator.to_sym