Passing variables to source files

[Sir Osis of Liver]

Is there a secure way to pass variables to source files from external script?  I've come up with a couple of methods that work, but don't believe they're safe to use.

[vbgamer45]

Lets see what you are doing if it does not seem secure will let you know.

[Sir Osis of Liver]

First method I tried, set up a form handler in the forum, post the variables from external script to the handler, it sets a cookie containing the variables, and Register.php reads values from the cookie.  That works.  Other method is a bit difficult to describe, and still haven't got it working, but basically involves creating a file that contains the variables, and Register.php picks it up as an include.