Find trigger of print

Hi Guys,

I have a question regarding the point a print was triggered. I try to explain:

I like to have a way to check if the print, for example of an billing document, was triggered because a new output was created in the billing document or if the user just clicked VF03->Billing Document->Issue Output to and then prints the form.

Do you know a way to differe between these to ways in the print program?

Thank you!