# File lib/thin/server.rb, line 225
      def select_backend(host, port, options)
        case
        when options.has_key?(:backend)
          raise ArgumentError, ":backend must be a class" unless options[:backend].is_a?(Class)
          options[:backend].new(host, port, options)
        when options.has_key?(:swiftiply)
          Backends::SwiftiplyClient.new(host, port, options)
        when host.include?('/')
          Backends::UnixServer.new(host)
        else
          Backends::TcpServer.new(host, port)
        end
      end