TcQueryInterface

TcQueryInterface 1:

The method queries the reference at an implemented interface over the ID.

TcQueryInterface 2: Return value

VAR_OUTPUT
    TcQueryInterface : HRESULT;
END_VAR

Name

Type

Description

TcQueryInterface

HRESULT

Informs about success of the interface query.
If the requested interface is not available, the method returns ADS_E_NOINTERFACE.

TcQueryInterface 3: Inputs

VAR_INPUT
    iid    : REFERENCE TO IID;
    pipItf : POINTER TO PVOID;
END_VAR

Name

Type

Description

iid

REFERENCE TO IID

Interface ID

pipItf

POINTER TO PVOID

Pointer to interface pointer. Is set when the requested interface type is available from the corresponding instance.

TcQueryInterface 4:

Necessary release of the interface pointers

You must explicitly release all references again. We recommend to use FW_SafeRelease in order to perform a release of the interface pointer after use. Frequently the release of the references is implemented in the destructor of the object.

Requirements

TwinCAT Version

Hardware

Libraries to be integrated

TwinCAT 3.1, Build 4020

x86, x64, ARM

Tc3_Module