Wordpress | Blog re-write url

gistfile1.txt

/* ==========================================================================
    If you want to utilize post types for blog and want blog to be 
    under a parent page about Ex: "/about/blog/". 
    
    Place the code below in your functions.php and change the paths 
    accordingly
========================================================================== */

function filter_post_link($permalink, $post) {
    if ($post->post_type != 'post')
        return $permalink;
    return 'about/blog'.$permalink;
}
add_filter('pre_post_link', 'filter_post_link', 10, 2);

add_action( 'generate_rewrite_rules', 'add_blog_rewrites' );
function add_blog_rewrites( $wp_rewrite ) {
    $wp_rewrite->rules = array(
        'about/blog/([^/]+)/?$' => 'index.php?name=$matches[1]',
        'about/blog/[^/]+/attachment/([^/]+)/?$' => 'index.php?attachment=$matches[1]',
        'about/blog/[^/]+/attachment/([^/]+)/trackback/?$' => 'index.php?attachment=$matches[1]&tb=1',
        'about/blog/[^/]+/attachment/([^/]+)/feed/(feed|rdf|rss|rss2|atom)/?$' => 'index.php?attachment=$matches[1]&feed=$matches[2]',
        'about/blog/[^/]+/attachment/([^/]+)/(feed|rdf|rss|rss2|atom)/?$' => 'index.php?attachment=$matches[1]&feed=$matches[2]',
        'about/blog/[^/]+/attachment/([^/]+)/comment-page-([0-9]{1,})/?$' => 'index.php?attachment=$matches[1]&cpage=$matches[2]',
        'about/blog/([^/]+)/trackback/?$' => 'index.php?name=$matches[1]&tb=1',
        'about/blog/([^/]+)/feed/(feed|rdf|rss|rss2|atom)/?$' => 'index.php?name=$matches[1]&feed=$matches[2]',
        'about/blog/([^/]+)/(feed|rdf|rss|rss2|atom)/?$' => 'index.php?name=$matches[1]&feed=$matches[2]',
        'about/blog/([^/]+)/page/?([0-9]{1,})/?$' => 'index.php?name=$matches[1]&paged=$matches[2]',
        'about/blog/([^/]+)/comment-page-([0-9]{1,})/?$' => 'index.php?name=$matches[1]&cpage=$matches[2]',
        'about/blog/([^/]+)(/[0-9]+)?/?$' => 'index.php?name=$matches[1]&page=$matches[2]',
        'about/blog/[^/]+/([^/]+)/?$' => 'index.php?attachment=$matches[1]',
        'about/blog/[^/]+/([^/]+)/trackback/?$' => 'index.php?attachment=$matches[1]&tb=1',
        'about/blog/[^/]+/([^/]+)/feed/(feed|rdf|rss|rss2|atom)/?$' => 'index.php?attachment=$matches[1]&feed=$matches[2]',
        'about/blog/[^/]+/([^/]+)/(feed|rdf|rss|rss2|atom)/?$' => 'index.php?attachment=$matches[1]&feed=$matches[2]',
        'about/blog/[^/]+/([^/]+)/comment-page-([0-9]{1,})/?$' => 'index.php?attachment=$matches[1]&cpage=$matches[2]',
    ) + $wp_rewrite->rules;
}