CA_ServerDllUnregisterServer

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Updated2023-02-21
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HRESULT CA_ServerDllUnregisterServer (HINSTANCE serverHInstance);

Purpose

Implementation of the DllUnregisterServer function used in the DLL ActiveX servers generated by the ActiveX Server Wizard. Installers and programmers use this function to unregister a COM DLL.

Parameters

Input
Name	Type	Description
serverHInstance	HINSTANCE	The HINSTANCE of your server. Note that the HINSTANCE is passed in as an argument to DllMain and WinMain. If your code uses main instead of WinMain as the module entry point, this value is not available. Therefore, EXE servers must use WinMain as their entry point.

Return Value

Name Type Description

status

HRESULT

A value indicating whether an error occurred. Function failure is indicated by a negative error code.

Error codes are defined in CVIversion\include\cviauto.h and <Program Files>\National Instruments\Shared\MSDTRedistributables\SDKHeaderFiles\8.1\winerror.h. The LabWindows/CVI ActiveX Library explicitly returns error codes. Other error codes in winerror.h are generated by the COM runtime and passed on to you by the ActiveX Library.

You can use CA_GetAutomationErrorString to get the description of an error code or CA_DisplayErrorInfo to display the description of the error code.

Note You should not return the ActiveX Library error codes from your ActiveX server to your ActiveX clients, unless you document them in your server documentation. An acceptable compromise in this case is to return E_UNEXPECTED to the clients.

The error codes defined in <Program Files>\National Instruments\Shared\MSDTRedistributables\SDKHeaderFiles\8.1\winerror.h are too numerous to display here. These error codes can be returned to your ActiveX clients.

Additional Information

Library: ActiveX Library

Include file: cviauto.h

LabWindows/CVI compatibility: LabWindows/CVI 6.0 and later