ref: 48c1eb6617cfcf9be0146a7991d34cb2d77cad97
dir: /sys/src/cmd/postscript/hardcopy/README/
Redirect output of the print operator to paper. Particularly useful if you're trying to extract information from a printer, but you don't have access to the data the printer returns to the host. For example, FontDirectory {pop ==} forall names all the fonts registered in the FontDirectory dictionary. Simple, but only if you can read the data returned to the host by the printer.