use wordpress as cms (not blog)

/* Kill attachment, search, author, daily archive pages */
add_action('template_redirect', 'custom_template_redirect');
function custom_template_redirect(){
    global $wp_query, $post;
 
    if (is_author() || is_attachment() || is_day() || is_search() || is_category())
    {
        $wp_query->set_404();
    }
 
    if (is_feed())
    {
        $author     = get_query_var('author_name');
        $attachment = get_query_var('attachment');
        $attachment = (empty($attachment)) ? get_query_var('attachment_id') : $attachment;
        $day        = get_query_var('day');
        $search     = get_query_var('s');
 
        if (!empty($author) || !empty($attachment) || !empty($day) || !empty($search))
        {
            $wp_query->set_404();
            $wp_query->is_feed = false;
        }
    }
}