code: public AsyncWork<File, IOException> createFileAsync(String prefix, String suffix) {
  		return new Task.OnFile<File, IOException>(tempDir, "Create temporary file", Task.PRIORITY_NORMAL) {
  			@Override
  			public File run() throws IOException {
  				return createFileSync(prefix, suffix);
  			}
  		}.start().getOutput();
  	}
docs: Create a temporary file.