Redirect users away from posts requiring membership with Paid Memberships Pro.

pmpro_customizations.php

<?php
/*
Plugin Name: PMPro Customizations
Plugin URI: http://www.paidmembershipspro.com/wp/pmpro-customizations/
Description: Customizations for Paid Memberships Pro
Version: .1
Author: Stranger Studios
Author URI: http://www.strangerstudios.com
*/

//redirect to login or homepage if user is logged out or not a member
function my_template_redirect_require_membership_access()
{
  if(!pmpro_has_membership_access())
	{
		 wp_redirect( wp_login_url() );
		exit;
	}
}
add_action('template_redirect', 'my_template_redirect_require_membership_access');