You could call it within the script with something like file('http://yoursite/thefile.php') but you'd have to be very carefull to prevent infinite recursion and to be honest there shouldn't be any reason why you would need to run the whole script more than once. You can always use loops around whatever code you need repeated.
HTH
Bubble
NB When I be very carefull, in theory you could knock your server down vey quickly. I've never tried it before but I'm going to see what happens now. If my box dies I'm holding you personally responsible 😉
[edit]
For me it just timed out. I only made a little test file.
<?php
echo('A test');
file('http://localhost/'.$_SERVER['php_self']);
?>
Also, this would fail on exeding memory limit as well because file will actually be returning data. You have to do it with fsockopen without retrieving any of the data, just firing of the call. In theory this will start up another call which will be completely independant and will also start off another call.
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