Is it possible to tie a callback/subroutine that will be automatically executed when another function/subroutine is called?

For example: If I call the built-in open() function, it does it's thing.

I would like to watch for calls to open() and execute my own subroutine at the same time (before or after, but automatically). Is this possible?

In reply to Tie subroutine to a built-in function call? by bcarroll

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