cupsFilter need to parse PPD file to get user options?

[anonymous]

I'm writing my own *cupsFilter. Do I have to parse both the ppd file and the 
user option list to support all user options?

After setting up queue options and print a test page, command line arguments 
#6 (options) to the filter is an empty list. So I suppose I have to parse 
PPD file to get options.

User might submit job through command line and overwrite options set in PPD 
file, so I have to parse that as well?

How about kprinter. I saw some strange options like orientation-requested=4 
multiple-document-handling=separate-documents-collated-copies, how am I 
supposed to do with it?

Thanks