code: function getCallerDirname() {
    var orig = Error.prepareStackTrace;
    Error.prepareStackTrace = function(_, stack){ return stack; };
    var err = new Error();
    Error.captureStackTrace(err, arguments.callee);
    var stack = err.stack;
    Error.prepareStackTrace = orig;
    var requester = stack[2].getFileName();
  
    return path.dirname(requester);
  }
docs: Gets the dirname of the caller function that is calling this method.
  @return {String}  Absolute path to the caller's directory.