DOCFIX: IoAttachDevice Will Work with Already Attached Device

Last reviewed: April 7, 1997
Article ID: Q128248

3.10 3.50 WINDOWS NT kbprg kbdocerr

The information in this article applies to:

Microsoft Win32 Device Development Kit (DDK) for Windows NT, versions 3.1 and 3.5

In the Windows NT DDK Kernel Mode Reference, the material for IoAttachDevice states that this call will return an error if TargetDevice is already attached. This is incorrect. If TargetDevice is already attached, the driver attempting to attach will layer itself on top of the topmost driver in the chain. For example, driver B is layered on top of driver A. Driver C then calls IoAttachDevice to driver A. When the system is done layering, the devices will be layered in the order C on top of B, which is on top of A.

Filter driver writers should never attempt to layer themselves above a file system.

This documentation error is corrected in the Win32 DDK version 3.51 online documentation.

Additional reference words: 3.10 3.50
KBCategory: kbprg kbdocerr
KBSubcategory:
Keywords : kbdocerr kbprg
Version : 3.10 3.50
Platform : NT WINDOWS

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Last reviewed: April 7, 1997
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