    # File lib/rack/handler/fastcgi.rb, line 32
          def self.valid_options
            environment  = ENV['RACK_ENV'] || 'development'
            default_host = environment == 'development' ? 'localhost' : '0.0.0.0'

            {
              "Host=HOST" => "Hostname to listen on (default: #{default_host})",
              "Port=PORT" => "Port to listen on (default: 8080)",
              "File=PATH" => "Creates a Domain socket at PATH instead of a TCP socket. Ignores Host and Port if set.",
            }
          end