# File lib/unicorn/configurator.rb, line 486
  def working_directory(path)
    # just let chdir raise errors
    path = File.expand_path(path)
    if config_file &&
       config_file[0] != ?/ &&
       ! File.readable?("#{path}/#{config_file}")
      raise ArgumentError,
            "config_file=#{config_file} would not be accessible in" \
            " working_directory=#{path}"
    end
    Dir.chdir(path)
    Unicorn::HttpServer::START_CTX[:cwd] = ENV["PWD"] = path
  end