caducar pagina al cerrar sesion

[Ronruby]

http://www.php.net/header

Example #2 Caching directives:
PHP scripts often generate dynamic content that must not be cached by the client browser or any proxy caches between the server and the client browser. Many proxies and clients can be forced to disable caching with:

Código PHP:

  <?php
header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1
header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past
?>   

http://blog.unijimpe.net/evitar-cache-con-php/