# File src/ruby_supportlib/phusion_passenger/platform_info/apache.rb, line 236
    def self.httpd_included_config_files(config_file, options = nil)
      state = {
        :files => { config_file => true },
        :unreadable_files => [],
        :root => httpd_default_root(options)
      }
      scan_for_included_apache2_config_files(config_file, state, options)
      return {
        :files => state[:files].keys,
        :unreadable_files => state[:unreadable_files]
      }
    end