Se non ho capito male dovrebbe restituire la base dato un indirizzo internet, però come cavolo si usa ? se faccio resolve_url($url) mi pare non funzioni.

Codice PHP:
function resolve_url($base$url) {         if (!strlen($base)) return $url;         // Step 2         if (!strlen($url)) return $base;         // Step 3         if (preg_match('!^[a-z]+:!i', $url)) return $url;         $base = parse_url($base);         if ($url{0} == "#") {                 // Step 2 (fragment)                 $base['fragment'] = substr($url, 1);                 return unparse_url($base);         }         unset($base['fragment']);         unset($base['query']);         if (substr($url, 0, 2) == "//") {                 // Step 4                 return unparse_url(array(                         'scheme'=>$base['scheme'],                         'path'=>$url,                 ));         } else if ($url{0} == "/") {                 // Step 5                 $base['path'] = $url;         } else {                 // Step 6                 $path = explode('/', $base['path']);                 $url_path = explode('/', $url);                 // Step 6a: drop file from base                 array_pop($path);                 // Step 6b, 6c, 6e: append url while removing "." and ".." from                 // the directory portion                 $end = array_pop($url_path);                 foreach ($url_path as $segment) {                         if ($segment == '.') {                                 // skip                         } else if ($segment == '..' && $path && $path[sizeof($path)-1] != '..') {                                 array_pop($path);                         } else {                                 $path[] = $segment;                         }                 }                 // Step 6d, 6f: remove "." and ".." from file portion                 if ($end == '.') {                         $path[] = '';                 } else if ($end == '..' && $path && $path[sizeof($path)-1] != '..') {                         $path[sizeof($path)-1] = '';                 } else {                         $path[] = $end;                 }                 // Step 6h                 $base['path'] = join('/', $path);          }         // Step 7         return unparse_url($base);