Print PDF from command line

@quangdog asked else where

Anyone here know how to print a PDF? (Note: Not print TO a PDF… to print an existing PDF to physical pieces of paper via an ancient machine known as a “printer”)
(specifically looking for how to print a PDF from a Xojo app without needing to involve some middleman pdf viewer software)

on macOS you can just send the pdf to the LPR daemon (this may work on Linux)
windows has nothing built in that I know of so there are creations like
there may be others - this was a quick google

It works on Linux with a shell command ‘lp [FILEPATH]’