[TYPO3] Hook, and how to access i.e. something liek piVars

[Matthias Stuebner]

Hello,

implementing my first hook I have trouble to find the right way to access
data.

Scenario:

- The hook uses contentPostProc-output to react when a even cached page is
called. The page of interest shows details of a product.

The id of the product to show is carried in a piVar i.e. itemID=3. And that
leads to my question:

How can I find which piVars were set for the specific cached page?

Inside my hook-function I can successfully access the tslib_fe object via
$reference->id etc., but how to get the piVars that were set when this page
was generated?

Any hint or pointer is highly welcome, Thanx in advance.
-- 
br Matthias