What is the difference between Minor IRPs and Major ones

What is the difference between IRP Major Function Codes and PnP IRP
Minor Function Code? The point of the question is what is Major and
what is Minor?

Thank you in advance!

kuasha
Thu Jul 12 03:22:03 CDT 2007

You should get the following document:

http://www.microsoft.com/whdc/driver/kernel/IRPs.mspx

It is a 21 pages (version - when writing this) word document every driver
writer should read.

--
--
Sincerely,
Maruf Maniruzzaman,
Software Engineer,
KAZ Software Limited,
Dhaka, Bangladesh.
http://www.kaz.com.bd
http://www.kuashaonline.com



"Yup" wrote:

> What is the difference between IRP Major Function Codes and PnP IRP
> Minor Function Code? The point of the question is what is Major and
> what is Minor?
>
> Thank you in advance!
>
>

Maxim
Thu Jul 12 04:48:00 CDT 2007

Major is large group, Minor is the sub-group in this large group.

--
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
maxim@storagecraft.com
http://www.storagecraft.com

"Yup" <yuppisll@hotmail.com> wrote in message
news:1184219411.426995.218030@57g2000hsv.googlegroups.com...
> What is the difference between IRP Major Function Codes and PnP IRP
> Minor Function Code? The point of the question is what is Major and
> what is Minor?
>
> Thank you in advance!
>

Mark
Thu Jul 12 06:11:20 CDT 2007

Yup wrote:
> What is the difference between IRP Major Function Codes and PnP IRP
> Minor Function Code? The point of the question is what is Major and
> what is Minor?
>
> Thank you in advance!
>
In addition to the other comments another difference is that major irps
are directly dispatched through your driver object to your individual
driver dispatch routines while their minor flavors have to be internally
processed (as appropriate) within those driver dispatch routines.

--

=====================
Mark Roddy DDK MVP
Windows Vista/2003/XP Consulting
Hollis Technology Solutions 603-321-1032
www.hollistech.com

Norman
Thu Jul 12 19:17:06 CDT 2007

Major Function Codes are those for which it takes a minor amount of time to
figure out what you need to do in your driver in order to handle them.

Minor Function Codes are those for which it takes a major amount of time to
figure out what you need to do in your driver in order to handle them.


"Yup" <yuppisll@hotmail.com> wrote in message
news:1184219411.426995.218030@57g2000hsv.googlegroups.com...
> What is the difference between IRP Major Function Codes and PnP IRP
> Minor Function Code? The point of the question is what is Major and
> what is Minor?
>
> Thank you in advance!
>