how to redirect when a page close using onunload in body tag?

[impin]

when the tab or the browser is closed the javascript should automatically redirect to the logout page.

<body onUnload="window.open('logout.php')">

<body onUnload= "re();";

both methods are not working...

// java script

function re()
{
self.location.href = "logout.php"
}

when the user closes the window the logout script should excute. but it not working