Sorry, but none of these

Data: Hashes (Associative Arrays)
   <<<snip>>>
   How can I get the unique keys from two hashes?
   <<<snip>>>
[download]

relate to my question.

You suffer from a failure of the imagination. The preceding item does relate to your question. It's the complementary action to the one you requested. Compute the list of unique keys and all your keys not on that list are the ones common to your two hashes. Alternatively, modify the algorithm to keep the keys that don't satisfy the uniqueness criterion and you have the list of keys you want.

If that's not obvious, you might want to reconsider your career choices...or at least refrain from posting snotty replies to any assistance you are given.

Sorry, but none of these (...) relate to my question.

Well, they are not the only topics in perlfaq4. I was referring to intersection of arrays. keys %hash is a list after all, and although the FAQ speaks of arrays, it works for lists as well.