how is __dirname implemented in Node.js?

Question

I am quite new to Node.js and have come across the "__dirname" and found it to be quite handy for getting the absolute directory path of the script. But I am curious as to how it is implemented, how is it able to understand the directory structure. I have gone through the node js source code but I am not able to find a proper answer.

Answer 1

these object are available globally to use in node create a file anywhere in your system with any name suppose app.js and write in that file

 console.log(__dirname);

run it like :-

    node app.js

it will print the path of current directory.