Printing to PDF (format of options???)

[Roger Eller]

*From the 5.5.3 docs:*

open printing to pdf "filename.pdf" with options tOptionArray

Ok, what exactly goes into tOptionsArray?  I don't see any specification
for the format of the options.  I would like to set the margins of the PDF
to .5" all around.  How can I do that without user input via page setup?
 Thanks.

~Roger