Генерация нового названия

function file_newname($path, $filename){
 if ($pos = strrpos($filename, '.')) {
 $name = substr($filename, 0, $pos);
 $ext = substr($filename, $pos);
 } else {
 $name = $filename;
 }
 
 $newpath = $path.'/'.$filename;
 $newname = $filename;
 $counter = 0;
 while (file_exists($newpath)) {
 $newname = $name .'_'. $counter . $ext;
 $newpath = $path.'/'.$newname;
 $counter++;
 }