$re = '/^\s*((?:(?<item>[^""\'\s,]+)|(?<quote>[""\'])(?<item>.*?)\<quote>)(?:(?:\s*,?\s*)|$))+$/i';
$str = ' /tmp/foo&bar / baz,quux \'etc., etc.\' "all well \'n good", \'3" of snow\' ';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php