call to undefined function php5

I'm writing a class to handle reading/writing from/to files like this
(shortened)

lass FileIO{
private $filename;
private $mode;
private $filePointer;
private $dictionary;

public function __construct($filename = null, $mode = 'r+'){
$this->filename = $filename;
$this->mode = $mode;
$this->filePointer = $this->openFile();
$this->dictionary = array();
}

public function openFile(){
return fopen($this->filename, $this->mode);
}

public function writeURL($name, $url){
$content = $name . " $ " . $url. "\n";
$this->fwrite($this->filePointer, $content);
}

when I try to call my writeURL(string, string) method the parser
returns an error of "call to undefined function)
my call:

include_once('FileIO.php');
$myFileIO = new FileIO('siv.txt');
$myFileIO.writeURL("siv", "nibbler.no");

this is copy/paste, so there's no typing error in the methodcall
(writeURL())
What am I doing wrong?

.

Relevant Pages