nWrite</a>, which returns an <a href="dart-io/IOSink-class.html">IOSink</a> to which you can write data.
Be sure to close the sink with the <a href="dart-io/IOSink/close.html">IOSink.close</a> method.</p>
<pre class="language-dart"><code>import 'dart:io';

void main() {
  var file = new File('file.txt');
  var sink = file.openWrite();
  sink.write('FILE ACCESSED ${new DateTime.now()}\n');

  // Close the IOSink to free system resources.
  sink.close();
}
</code></pre>
<h2 id="the-use-of-futures">The use of 