# File lib/specinfra/command/module/ss.rb, line 5
        def check_is_listening(port, options={})
          if options[:local_address]
            pattern = inaddr_any_to_asterisk(options[:local_address]).map { |l| " #{l}:#{port} " }
            pattern = pattern.join('|')
          else
            pattern = ":#{port} "
          end
          "ss #{command_options(options[:protocol])} | grep -E -- #{escape(pattern)}"
        end