code: function mkdir(affixes, callback) {
    var dirPath = generateName(affixes, 'd-');
    fs.mkdir(dirPath, parseInt('0700', 8), function(err) {
      if (!err) {
        deleteDirOnExit(dirPath);
      }
      if (callback) {
        callback(err, dirPath);
      }
    });
  }
docs: /* DIRECTORIES