add_action( 'init', 'add_post_type_event' );
function add_post_type_event() {
flush_rewrite_rules( false );
    register_post_type( 'd3ms4_event',
        array(
            'labels' => array(
                'name' => __( 'Events' ),
                'singular_name' => __( 'Events' ),
                'add_new' => __( 'Add New Event' ),
                'add_new_item' => __( 'Add New Event' ),
                'edit_item' => __( 'Edit Event' ),
                'new_item' => __( 'Add New Event' ),
                'view_item' => __( 'View Event' ),
                'search_items' => __( 'Search Event' ),
                'not_found' => __( 'No event found' ),
                'not_found_in_trash' => __( 'No event found in trash' )
                ),
            'public' => true,  // it's not public, it shouldn't have it's own permalink, and so on
            'publicly_queriable' => true,  // you should be able to query it
            'show_ui' => true,  // you should be able to edit it in wp-admin
            'exclude_from_search' => true,  // you should exclude it from search results
            'show_in_nav_menus' => true,  // you shouldn't be able to add it to menus
            'has_archive' => true,  // it shouldn't have archive page
            'rewrite' => array( 'slug' => 'event' ),  // it shouldn't have rewrite rules
            'supports' => array('title', 'editor', 'thumbnail'),
            'capability_type' => 'post',
            'menu_icon'   => 'dashicons-calendar-alt',
            'menu_position' => 5
            )
        );
}