Parallel port query

[Frank BENNETT <bennett@example.com>]

I have set up a Linux box here to spool jobs to the parallel port of a laser
printer.  It would be nifty if the spooling software could be made sensitive
to the status of the printer, so that the latter could be powered up only
when needed.

Is there any means of polling the parallel port to see if a live device is
attached to it?  I've checked under /proc/parport, but it reports only on
the port itself.

The printer has a serial interface as well; if I'm not going to get anywhere
with the parallel port, can this be accomplished on the serial port?

Yours in hope,
Frank Bennett