Classes and Priorities

[Timetrinus]

Hello!

We are creating postscript files that are transferred to 3g / gprs connected laptops in the field via lpd. For doing this every laptop has a so called "Mobile" printqueue. This Printqueue defaults to a cups-pdf backend. But in case the user connects a usb printer the printjob has to be printed out there instead of creating a PDF.

I thought about cups classes for automatically handling this behaviour. So I would create a class Mobile and put in a PDF-Printer and if user connects a USB Printer add it to this class. But: is it possible to configure the class to use PDF-Printer only if no other printer is configured in the queue? Disabeling the PDF-Printer in case the User connects a USB Printer is not a good Idea because from local Applications (for example openoffice, or browser) the user should be able to create PDF output every time.

Thanks in advance!