Peerlibrary:fs readFileSync and Meteor

I need to read a file on the server, parse it then load it in an array.
I installed peerlibrary:fs and created a class like this:

ProvidersDictionary = function() {
  var start = new Date().getTime();

  this.providers = fs.readFileSync('/free-email-providers.txt').toString().split('\n');

  this.lookUp = function(domain) {
    return (this.providers.indexOf(domain) !== -1)? true : false;
  }
}

free-email-providers.txt is in the /public folder, but can anywhere on the server. I keep having this error:

Error: ENOENT, open ‘/free-email-providers.txt’

Any ideas?
Any other easier way to do the same tasks?

[UPDATE]
Solved this using process.env.PWD :

this.providers = fs.readFileSync(process.env.PWD + ‘/server/dictionaries/free-email-providers.txt’).toString().split(’\n’);

I just discovered that this solution doesn’t work when I deploy my app to *.meteor.com.

Can you help me?