OB_CALLBACK_REGISTRATION structure (wdm.h)

The OB_CALLBACK_REGISTRATION structure specifies the parameters when the ObRegisterCallbacks routine registers ObjectPreCallback and ObjectPostCallback callback routines.

Syntax

typedef struct _OB_CALLBACK_REGISTRATION {
  USHORT                    Version;
  USHORT                    OperationRegistrationCount;
  UNICODE_STRING            Altitude;
  PVOID                     RegistrationContext;
  OB_OPERATION_REGISTRATION *OperationRegistration;
} OB_CALLBACK_REGISTRATION, *POB_CALLBACK_REGISTRATION;

Members

Version

The version of object callback registration that is requested. Drivers should specify OB_FLT_REGISTRATION_VERSION.

OperationRegistrationCount

The number of entries in the OperationRegistration array.

Altitude

A Unicode string that specifies the altitude of the driver. For more information about altitude, see Load Order Groups and Altitudes for Minifilter Drivers.

RegistrationContext

The system passes the RegistrationContext value to the callback routine when the callback routine is run. The meaning of this value is driver-defined.

OperationRegistration

A pointer to an array of OB_OPERATION_REGISTRATION structures. Each structure specifies ObjectPreCallback and ObjectPostCallback callback routines and the types of operations that the routines are called for.

Remarks

This structure is used by the ObRegisterCallbacks routine. The CallBackRegistration parameter to this routine is a pointer to a buffer that contains an OB_CALLBACK_REGISTRATION structure that is followed by an array of one or more OB_OPERATION_REGISTRATION structures.

Requirements

Requirement	Value
Minimum supported client	Available starting with Windows Server 2008.
Header	wdm.h (include Wdm.h, Ntddk.h, Ntifs.h)

See also

OB_OPERATION_REGISTRATION

ObRegisterCallbacks

ObjectPostCallback

ObjectPreCallback