fs.mkdirSync(path, [mode])

var fs = require('fs');
var creats = fs.mkdirSync('creatdir2', 0777);
console.log(creats);

fs.mkdirSync = function(path, mode) {
  nullCheck(path);
  return binding.mkdir(pathModule._makeLong(path),
                       modeNum(mode, 511 /*=0777*/));
};