A simple utility module we used to detect the version of OS X currently running in order to work around the oracle-instant-client segfault problem.

osx_compat.rb

module OSXCompat
  OSX_REGEX = /darwin\d{2}/
  SNOW_KITTY = "darwin10"

  class << self
    
    def snow_kitty_or_lower?
      if darwin?
        osx_version <= SNOW_KITTY
      else
        true #always return true for every other env
      end
    end

    def use_oracle?
      eval_environment_value_or_fallback 'USE_ORACLE', :snow_kitty_or_lower?
    end

    def use_image_tools?
      eval_environment_value_or_fallback 'USE_IMAGE_TOOLS', :lion_or_higher?
    end

    def lion_or_higher?
      !snow_kitty_or_lower?
    end

    def darwin?
      !osx_version.nil?
    end

    def osx_version
      RUBY_PLATFORM.slice OSX_REGEX
    end

    protected

    def eval_environment_value_or_fallback(value, fallback)
      v = ENV[value]
      v && v =~ /\Atrue|false\Z/ ? eval(v) : send(fallback)
    end

  end

end