you can do this:
fs.readFile(path.resolve(__dirname, 'settings.json'), 'UTF-8', callback);
Use resolve() instead of concatenating with '/' or '\' else you will run into cross-platform issues.
Note: __dirname is the local path of the module or included script. If you are writing a plugin which needs to know the path of the main script it is:
or, to just get the folder name:
Hope it helps!!