php-【PHP】uchome上传视频时如何得到可用空间

<code>        $userid = $_POST['supe_uid'];        $space = getspace($userid);        $maxattachsize = checkperm('maxattachsize');//单位MB        echo 'maxattachsize：'.$maxattachsize.'addsize:'.$space['addsize'].'attachsize:'.$space['attachsize'].'filesize:'.$FILE['size'];exit;        if($maxattachsize) {//0为不限制            if($space['attachsize'] + $FILE['size'] > $maxattachsize + $space['addsize']) {                echo "剩余空间不足，上传失败";                exit;            }        }</code>