FltCloseClientPort function (fltkernel.h)

Article
10/21/2021

FltCloseClientPort closes a communication client port.

Syntax

VOID FLTAPI FltCloseClientPort(
  [in]  PFLT_FILTER Filter,
  [out] PFLT_PORT   *ClientPort
);

Parameters

[in] Filter

Opaque filter pointer for the caller. This parameter is required and cannot be NULL.

[out] ClientPort

Pointer to a variable that contains the opaque port handle for the client port to be closed. On return, the variable receives NULL. This parameter is required and cannot be NULL on input.

Return value

None

Remarks

A minifilter driver normally calls FltCloseClientPort from the DisconnectNotifyCallback routine that it registered when it called FltCreateCommunicationPort. The Filter Manager calls the DisconnectNotifyCallback routine whenever the user-mode handle count for the client port reaches zero or when the minifilter driver is about to be unloaded.

FltCloseClientPort closes a communication client port that was created by the minifilter driver's ConnectNotifyCallback routine.

On input, the ClientPort parameter is a pointer to a variable containing the opaque handle for the client port to be closed. To ensure that any messages sent by FltSendMessage are synchronized properly when the communication client port is being closed, FltCloseClientPort sets this variable to NULL.

This routine disconnects a specific connection from the minifilter driver. To close the handle for the minifilter driver's server port, which listens for incoming connections, use FltCloseCommunicationPort.

Requirements

Requirement	Value
Target Platform	Universal
Header	fltkernel.h (include Fltkernel.h)
Library	Fltmgr.lib
DLL	Fltmgr.sys
IRQL	PASSIVE_LEVEL