Meta Description on Pages

Enable the automatic generation of the meta description on pages in WordPress.

function create_meta_desc() {
     global $post;
 if (!is_page()) { return; }
     $meta = strip_tags($post->post_content);
     $meta = strip_shortcodes($post->post_content);
     //$meta = str_replace(array("\n", "\r", "\t"), ' ', $meta);
     $meta = str_replace( array("\n", "\r", "\t", "", "
", ""), ' ', $meta );
     $meta = substr($meta, 0, 125);
     echo "
";
 }
 add_action('wp_head', 'create_meta_desc');