CI, SimplePie and server write permissions!

[eluser]jk215[/eluser]
Hey everyone. Im trying to get Simplepie to cache results but I keep getting the dreaded "cache folder is unwritable" error.

Setup: Codeigniter 2.1.0 / PHP 5.2.x / Simplepie 1.2.1

I tried using the default ./cache directory listed in Simplepie and also my own cache folder outside of /application and /system. I am certain permissions are set at 777 right now.

I ran this little test:

Code:

function index()
    {
$this->load->helper('file');
        $data = 'Some file data';

        if ( ! write_file(base_url() . 'cache_files/testest.php', $data))
          {
           echo 'Unable to write the file';
          }
       else
          {
         echo 'File written!';
          }

It came back with unable to write the file. Is there something weird I need to know about CI writing to folders? Its pissing me off because everything works fine without cache but I need it! Any help is appreciated!

[eluser]Aken[/eluser]
Use absolute paths, not HTTP paths when writing folders and files.

[eluser]jk215[/eluser]
Yeah I think that was it. Used APPPATH instead and there is no more error. Thanks!