Post ID wrong in Functions.php

Try this:

function filter_pagetitle($url) {

        global $post;            

        return $post->post_title;
}

add_filter('wp_title', 'filter_pagetitle');

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)