$xmldata='SOURCE_URL.xml';
$csvFile = 'results.csv';
$xPath = '//product';
$delimiter = ',';
One of this array must be empty, or INCLUDE columns, or EXCLUDE:
$included_columns = array(); $excluded_columns = array('description');
xml2csv($xmldata, $csvFile, $xPath, $included_columns, $excluded_columns, $delimiter);