node.js - Does the second parameter `options` exists for `readdir` function in `fs` module? -

when pass "utf8" second parameter readdir function in fs module (https://nodejs.org/api/fs.html#fs_fs_readdir_path_options_callback), gives following error:

fs.js:78 throw new typeerror('callback must function'); ^

see following snippets:

snippet #1

var fs = require("fs"); fs.readdir(process.argv[2], "utf8", function(){     console.log(arguments); });

snippet #2

var fs = require("fs"); fs.readdir(process.argv[2], function(){     console.log(arguments); });

snippet #1 throws error, while snippet #2 works.

why happen? doesn't readdir function have second optional parameter?

you might running older version of node.js.

this added in v6.0.0.

CSS