Windows System Software -- Consulting, Training, Development -- Unique Expertise, Guaranteed Results


Before Posting...

Please check out the Community Guidelines in the Announcements and Administration Category.

More Info on Driver Writing and Debugging

The free OSR Learning Library has more than 50 articles on a wide variety of topics about writing and debugging device drivers and Minifilters. From introductory level to advanced. All the articles have been recently reviewed and updated, and are written using the clear and definitive style you've come to expect from OSR over the years.

Check out The OSR Learning Library at:


ArsenArsen Member Posts: 91

Can I use METHOD_IN_DIRECT and METHOD_OUT_DIRECT together. When I want to send and receive buffer from driver.
like this


The CTL_CODE macro defines 2 bits for this, so I think we can't assign both methods. Then, how to send and receive buffers to and from the driver using a single IRP.


  • Mark_RoddyMark_Roddy Member - All Emails Posts: 4,605

    If it is writable it is readable.

  • Tim_RobertsTim_Roberts Member - All Emails Posts: 14,482

    No, you can't use them together. Those are not bits, they are enumerations. In fact, that particular combination would be very bad, because METHOD_IN_DIRECT (1) ored with METHOD_OUT_DIRECT (2) gives you 3, which is METHOD_NEITHER. And nobody wants that.

    However, for all practical purposes, the two are identical.

    Tim Roberts, [email protected]
    Providenza & Boekelheide, Inc.

  • ArsenArsen Member Posts: 91

    Thanks everyone

Sign In or Register to comment.

Howdy, Stranger!

It looks like you're new here. Sign in or register to get started.

Upcoming OSR Seminars
OSR has suspended in-person seminars due to the Covid-19 outbreak. But, don't miss your training! Attend via the internet instead!
Kernel Debugging 30 January 2023 Live, Online
Developing Minifilters 20 March 2023 Live, Online
Internals & Software Drivers 17 April 2023 Live, Online
Writing WDF Drivers 22 May 2023 Live, Online