Didier Kryn writes:

>     You're certainly right: it isn't simple. But it's 
> essential, isn't it?. Graphics printing reached the personnal 
> computer probably with the first McIntosh, in 1982. <rant>Not 
> sure it's more feature-rich today than 10 years ago, when it 
> wasn't depending on dbus.</rant>

I wrote a printer driver back then. It used user-bus. "Tell me, dear user,
whether the printer has and supports. A4 or funny american paper? Duplex?"

If I were more ambitious I'd have asked more complicated questions. For
example, if you want to avoid printer firmware bugs it's generally smart to
send a large bitmap, but if you aim for high quality output and a high page
rate, you want to avoid sending bitmaps. Can't ask users about such
tradeoffs, they will be annoyed and won't be able to answer. These days you
can ask the printer via d-bus. The printer knows more about itself than its
users know about it.

Arnt