user auth. and cookies

[Anon]

Visitors to my site should be able to browse the site without logging in. If at some stage(say for example when viewing order.php), they want to log, they can then log and the same page is displayed(i.e. order.php). If they don't have username, they'll create one and order.php is shown after sign up. Please help.

[mp96brbj]

On every page, have these links:
<a href="reg.php?referer=<?php echo urlencode($PHP_SELF); ?>">Register</a>
<a href="log.php?referer=<?php echo urlencode($PHP_SELF); ?>">Log in</a>

In the forms on these pages, pass along $referer as a hidden input.

Then, when they have registered or logged in, start a session (if you want to store their user auth that way) and write:
header("Location: $referer");