SQLRemoveDriverManager

Conformance

Version Introduced: ODBC 3.0

Summary

SQLRemoveDriverManager changes or removes information about the ODBC core components from the ODBCINST.INI entry in the system information.

Syntax

BOOL SQLRemoveDriverManager (
LPDWORD pdwUsageCount);

Arguments

pdwUsageCount [Output]
The usage count of the Driver Manager after this function has been called.

Returns

The function returns TRUE if it is successful, FALSE if it fails. If no entry exists in the system information when this function is called, the function returns FALSE.

Diagnostics

When SQLRemoveDriverManager returns FALSE, an associated *pfErrorCode value may be obtained by calling SQLInstallerError. The following table lists the *pfErrorCode values that can be returned by SQLInstallerError and explains each one in the context of this function.

*pfErrorCode

Error

Description

ODBC_ERROR_ GENERAL_ ERR	General installer error	An error occurred for which there was no specific installer error.
ODBC_ERROR_ COMPONENT_ NOT_FOUND	Component not found in registry	The installer could not remove the Driver Manager information because it either did not exist in the registry or could not be found in the registry.
ODBC_ERROR_ USAGE_ UPDATE_FAILED	Could not increment or decrement the component usage count	The installer failed to decrement the usage count of the Driver Manager.
ODBC_ERROR_ OUT_OF_MEM	Out of memory	The installer could not perform the function because of a lack of memory.

Comments

SQLRemoveDriverManager complements the SQLInstallDriverManager function, and updates the component usage count in the system information. This function should only be called from a setup application.

SQLRemoveDriverManager will decrement the core component usage count by 1. If the component usage count goes to 0, then the entry system information will be removed. The core component entry is in the following location in the system information, under the title "ODBC Core":

HKEY_LOCAL_MACHINE
SOFTWARE
ODBC
ODBCINST.INI

Caution An application should not physically remove Driver Manager files when the component usage count and the file usage count reach zero.

SQLRemoveDriverManager does not actually remove any files. The calling program is responsible for deleting files and maintaining the file usage counts. Driver Manager files should not, however, be removed when both the component usage count and the file usage count have reached zero, because these files may be used by other applications that have not incremented the file usage count.

SQLRemoveDriverManager is called as part of the Uninstall process. ODBC core components (which include the Driver Manager, Cursor Library, Installer, Language Library, Administrator, thunking files, and so on) are uninstalled as a whole. The following files are not removed when SQLRemoveDriverManager is called as part of the Uninstall process:

ODBC32DLL	ODBCCP32.DLL
ODBCCR32.DLL	ODBC16GT.DLL
ODBCCU32.DLL	ODBC32GT.DLL
ODBCINT.DLL	DS16GT.DLL
ODBCTRAC.DLL	DS32GT.DLL
MSVCRT40.DLL	ODBCAD32.EXE
ODBCCP32.CPL

SQLRemoveDriverManager is also called as part of an upgrade process. If an application detects that it has to perform an upgrade, and it has previously installed the driver, then the driver should be removed, and then reinstalled. SQLRemoveDriverManager should first be called to decrement the component usage count. SQLInstallDriverEx should then be called to increment the component usage count. The application setup program must physically replace the old core component files with the new files. The file usage counts will remain the same, and other applications that use the older version core component files will now use the newer version files.

Related Functions

For information about

See

Installing a Driver Manager

SQLInstallDriverManager