trackback( string $trackback_url, string $title, string $excerpt, int $post_id ): int|false|void

3209function trackback( $trackback_url, $title, $excerpt, $post_id ) {3210	global $wpdb;3211 3212	if ( empty( $trackback_url ) ) {3213		return;3214	}3215 3216	$options            = array();3217	$options['timeout'] = 10;3218	$options['body']    = array(3219		'title'     => $title,3220		'url'       => get_permalink( $post_id ),3221		'blog_name' => get_option( 'blogname' ),3222		'excerpt'   => $excerpt,3223	);3224 3225	$response = wp_safe_remote_post( $trackback_url, $options );3226 3227	if ( is_wp_error( $response ) ) {3228		return;3229	}3230 3231	$wpdb->query( $wpdb->prepare( "UPDATE $wpdb->posts SET pinged = CONCAT(pinged, '\n', %s) WHERE ID = %d", $trackback_url, $post_id ) );3232	return $wpdb->query( $wpdb->prepare( "UPDATE $wpdb->posts SET to_ping = TRIM(REPLACE(to_ping, %s, '')) WHERE ID = %d", $trackback_url, $post_id ) );3233}