Need advice on printer drivers.

[Michael_Anthony_Domino at cup.portal.com]

I need some advice, and maybe some sample code to write a printer driver.
I've done this kind of thing before, but not on a Unix system (PCs, Macintosh)
It's for a color thermal transfer printer, and I'll be working on an HP work-
station, using their version of System V.  I'd appreciate it greatly if
anyone could also recommend manuals, articles or books on the subject. How
big a job could this turn out to be?  I need to provide some kind of time
estimate to the customer.

Thanks,
Michael Domino