def start
      setup_signal_handlers
      @server = WEBrick::HTTPServer.new(options)
      @server.mount '/', Rack::Handler::WEBrick, app
      @server.start
    end
def start
      setup_signal_handlers
      @server = WEBrick::HTTPServer.new(options)
      @server.mount '/', Rack::Handler::WEBrick, app
      @server.start
    end
Start server. Raises Errno::EADDRINUSE if port is in use by another
 process. Raises Errno::EACCES if binding to the port requires root
 privilege.