When using a php script like a remote function call, I find something like this useful for setting default parameters.
<?php
function get_params($defaults = null, $overwrite = false, $super_globals = array('_GET', '_POST', '_COOKIE'))
{
$ret = array();
foreach($super_globals as $sg)
foreach($GLOBALS[$sg] as $k=>$v)
$ret[$k] = $v;
if($defaults) foreach($defaults as $k=>$v)
if(!isset($ret[$k]))
$ret[$k] = $v;
if($overwrite)
$_REQUEST = $ret;
return $ret;
}
$argv = get_params(array('id'=>42, 'style'=>'medieval'));
?>