Schedule tasks help

[TheSupportForum]

i need to run a schedule task to rename a file

so far i have this

PHP Code:


$logfile = $vbulletin->options['aglogfile'];
$logurl = $vbulletin->options['aglogurl'];
$logname = $vbulletin->options['aglogname'];

echo "backup of your file

";
echo "Finished

";
rename ("$logurl/$logname","$logurl/$logname". date("d-M-Y", time()) . ".txt");
echo "C'est fini. You can view your logs
\n
"; 


the variables work but i get an error message

PHP Code:

Warning: rename() [function.rename]: http wrapper does not support renaming 


can anyone help on a better solution or help resolve the error message