Parallel port filter - what is a MicrosoftRawPort?

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I am trying to capture the data that flows across a parallel port. I have
used the DDK's Toaster Upper Filter sample to install an upper class filter
for the ports class. However, my filter is not getting any IRP's when
something is printed to LPT1. It does get PnP IRP's if I disable the port
from Device Manager so I know that my filter is installed at least somewhere.
I also get IRP's when something is sent to a serial port since my filter is
installed as a class filter. Here are my questions:

1) What is the difference between Parallel0 and ParallelPort0? I get the
feeling that I am installed as an upper filter of ParallelPort0 and not of
Parallel0 even though they both use the parport.sys service.

2) What is a MicrosoftRawPort? Parallel0 is considered a MicrosoftRawPort
device which does not use the ACPI device object. It is also the device that
appears to be getting all of the IRP's.

3) Is the MicrosoftRawPort class found on all computers or just some?

4) How would I attach an upper filter to Parallel0 instead of just
ParallelPort0?

5) Why does the parallel port behave differently from the serial port? My
filter works great for seriall port devices. I would expect the same behavior
for parallel ports.

6) Is there an easier way to do this? Can what I want to do be accomplished
from user mode code without writing a driver?

Thanks,
Matt

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