Hi,

I'm new to device driver writing and would like a quick pointer about which
direction to go. I need to filter messages on the modem (e.g via RAS) and
if a certain string is sent to the modem (e.g. ATDT) then display a dialog
to the user to ask whether they should allow it or not.

I have seen many examples of filter drivers and the Alex Bessonov WDJ 98
article seems a good, clean simple starting point although NuMega have a
good sample in Driverworks too.

I can see the code where the IRP_MJ_WRITE is done and can change the buffer
to prevents text being sent (change text to spaces), but what is the best
technique to queue the request and then wait for a response from the user.
I assume I need to have a user mode app and commmunicate with it via IOCTL,
but what is the best way to hold off the IRP_MJ_WRITE request until the user
dialog is answered?

Thanks a lot
Paul Bartlett