# File src/ruby_supportlib/phusion_passenger/standalone/control_utils.rb, line 44
      def warn_pid_file_not_found(options)
        if options[:pid_file]
          STDERR.puts "According to the PID file '#{options[:pid_file]}',"
          STDERR.puts "#{PROGRAM_NAME} Standalone doesn't seem to be running."
        else
          STDERR.puts "#{PROGRAM_NAME} Standalone doesn't seem to be running, " +
            "because its PID file"
          STDERR.puts "could not be found."
        end
        STDERR.puts
        STDERR.puts "If you know that #{PROGRAM_NAME} Standalone *is* running then one of these"
        STDERR.puts "might be the cause of this error:"
        STDERR.puts
        STDERR.puts " * The #{PROGRAM_NAME} Standalone instance that you want to stop isn't running"
        STDERR.puts "   on port #{options[:port]}, but on another port. If this is the case then you"
        STDERR.puts "   should specify the right port with --port."
        STDERR.puts "   If the instance is listening on a Unix socket file instead of a TCP port,"
        STDERR.puts "   then please specify the PID file's filename with --pid-file."
        STDERR.puts " * The instance that you want to stop has stored its PID file in a non-standard"
        STDERR.puts "   location. In this case please specify the right PID file with --pid-file."
      end