IRP_MN_QUERY_INTERFACE : What is it different in XP ?

NTDEV
1

Hi all

I am having some problem with IRP_MN_QUERY_INTERFACE in windows XP . As per
Walter oney’s book, in the multifunction sample , for a child device this
query is ignored . As per XP ddk , we need to handle this IOCTL if the
driver is bus driver . And windows 2000 does work fine even when we ignore
the IRP_MN_QUERY_INTERFACE request ( that means completing the request in
the Child Pnp handler ) . Anybody know why is this difference ?
Can anybody fill me with what exactly I need in this case ? What do I send
when I get a IRP_MN_QUERY_INTERFACE in child PnP handler ?

Thanks in advance
srinivasa

2

“Deevi, Srinivasa” wrote:

I am having some problem with IRP_MN_QUERY_INTERFACE in windows XP . As per
Walter oney’s book, in the multifunction sample , for a child device this
query is ignored . As per XP ddk , we need to handle this IOCTL if the
driver is bus driver . And windows 2000 does work fine even when we ignore
the IRP_MN_QUERY_INTERFACE request ( that means completing the request in
the Child Pnp handler ) . Anybody know why is this difference ?
Can anybody fill me with what exactly I need in this case ? What do I send
when I get a IRP_MN_QUERY_INTERFACE in child PnP handler ?

I didn’t need to change MULFUNC for XP. Certainly, you can just complete
the IRP with the status code that’s already in the IRP if you don’t
recognize the interface guid.

–
Walter Oney, Consulting and Training
Basic and Advanced Driver Programming Seminars
Now teaming with John Hyde for USB Device Engineering Seminars
Check out our schedule at http://www.oneysoft.com