revPrintField ???? PDF

[Richmond Mathewson]

  on mouseUp
   revPrintField the name of fld "TTEXT"
end mouseUp

gives me (on Mac OS X) a standard print dialog (without the print to PDF 
option)

the documentation (PDF) has this:

"On Mac OS X systems you can also print directly to a PDF file
-- even without showing the user a print dialog if choose to."

which is lovely - but nowhere can I find details on how to
effect this . . .

nor printing to XPS on Windows.