FltUnregisterFilter function (fltkernel.h)

Article
02/22/2024

A registered minifilter driver calls FltUnregisterFilter to unregister itself so that the Filter Manager no longer calls it to process I/O operations.

Syntax

VOID FLTAPI FltUnregisterFilter(
  [in] PFLT_FILTER Filter
);

Parameters

[in] Filter

Opaque filter pointer returned by FltRegisterFilter.

Return value

None

Remarks

FltUnregisterFilter unregisters the minifilter driver's callback routines and removes any contexts that the minifilter driver has set on files, volumes, instances, streams, or stream handles. It also calls the minifilter driver's InstanceTeardownStartCallback and InstanceTeardownCompleteCallback (PFLT_INSTANCE_TEARDOWN_CALLBACK) routines for each minifilter driver instance.

A minifilter driver typically calls FltUnregisterFilter from its unload routine when it is about to be unloaded.

A minifilter driver can only call FltUnregisterFilter to unregister itself, not another minifilter driver.

To register a minifilter driver, call FltRegisterFilter.

Requirements

Requirement	Value
Target Platform	Universal
Header	fltkernel.h (include Fltkernel.h)
Library	FltMgr.lib
DLL	Fltmgr.sys
IRQL	<= APC_LEVEL