How Crème Fraiche creates temporary directories

    # Creates a temporary directory upon the first call but always returns its path
    # Stolen from Alex Chaffee's files-gem and
    # http://stackoverflow.com/questions/1139265/what-is-the-best-way-to-get-a-temporary-directory-in-ruby-on-rails
    def temp_dir options = {:remove => true}
        @temp_dir ||= begin
                      @log.debug('creating temp_dir')
                      require 'tmpdir'
                      require 'fileutils'
                      #
                      # called_from = File.basename caller.first.split(':').first, ".rb"
                      called_from = CremeFraiche::prog_info[:app_name].gsub(' ', '_')
                      @log.debug('called_from is ' << called_from)
                      path = File.join(Dir::tmpdir, "#{called_from}_#{Time.now.to_i}_#{rand(1000)}")
                      @log.debug('temp-dir path is ' << path)
                      Dir.mkdir(path)
                      at_exit {FileUtils.rm_rf(path) if File.exists?(path)} if options[:remove]
                      File.new path
                  end
    end