# File lib/cgikit/resource.rb, line 405
    def set_data( data, key, mime )
      super
      unless FileTest.directory? @tmpdir
        require 'ftools'
        File.makedirs @tmpdir
      end
      cache = {}
      cache[:data] = data
      cache[:key]  = key
      cache[:mime] = mime
      FileLock.exclusive_lock(tmpfile(key)) do |file|
        Marshal.dump(cache, file)
      end
    end