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SQLConfigDriver Function

Conformance
Version Introduced: ODBC 2.5

Summary
SQLConfigDriver loads the appropriate driver setup DLL and calls the ConfigDriver function.

The functionality of SQLConfigDriver can also be accessed with ODBCCONF.EXE.

Syntax

  
BOOL SQLConfigDriver(  
     HWND     hwndParent,  
     WORD     fRequest,  
     LPCSTR   lpszDriver,  
     LPCSTR   lpszArgs,  
     LPSTR    lpszMsg,  
     WORD     cbMsgMax,  
     WORD *   pcbMsgOut);  

Arguments

hwndParent
[Input] Parent window handle. The function will not display any dialog boxes if the handle is null.

fRequest
[Input] Type of request. fRequest must contain one of the following values:

ODBC_CONFIG_DRIVER: Changes the connection pooling timeout used by the driver.

ODBC_INSTALL_DRIVER: Installs a new driver.

ODBC_REMOVE_DRIVER: Removes an existing driver.

This option can also be driver-specific, in which case the fRequest for the first option must start from ODBC_CONFIG_DRIVER_MAX+1. The fRequest for any additional option must also start from a value greater than ODBC_CONFIG_DRIVER_MAX+1.

lpszDriver
[Input] The name of the driver as registered in the system information.

lpszArgs
[Input] A null-terminated string that contains arguments for a driver-specific fRequest.

lpszMsg
[Output] A null-terminated string that contains an output message from the driver setup.

cbMsgMax
[Input] Length of lpszMsg.

pcbMsgOut
[Output] Total number of bytes available to return in lpszMsg. If the number of bytes available to return is greater than or equal to cbMsgMax, the output message in lpszMsg is truncated to cbMsgMax minus the null-termination character. The pcbMsgOut argument can be a null pointer.

Returns

The function returns TRUE if it is successful, FALSE if it fails.

Diagnostics

When SQLConfigDriver returns FALSE, an associated *pfErrorCode value can 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_INVALID_BUFF_LEN Invalid buffer length The lpszMsg argument was invalid.
ODBC_ERROR_INVALID_HWND Invalid window handle The hwndParent argument was invalid.
ODBC_ERROR_INVALID_REQUEST_TYPE Invalid type of request The fRequest argument was not one of the following:

ODBC_INSTALL_DRIVER ODBC_REMOVE_DRIVER

The fRequest argument was a driver-specific option that was less than or equal to ODBC_CONFIG_DRIVER_MAX.
ODBC_ERROR_INVALID_NAME Invalid driver or translator name The lpszDriver argument was invalid. It could not be found in the registry.
ODBC_ERROR_INVALID_KEYWORD_VALUE Invalid keyword-value pairs The lpszArgs argument contained a syntax error.
ODBC_ERROR_REQUEST_FAILED Request failed The installer could not perform the operation requested by the fRequest argument. The call to ConfigDriver failed.
ODBC_ERROR_LOAD_LIBRARY_FAILED Could not load the driver or translator setup library The driver setup library could not be loaded.
ODBC_ERROR_OUT_OF_MEM Out of memory The installer could not perform the function because of a lack of memory.

Comments

SQLConfigDriver allows an application to call a driver's ConfigDriver routine without having to know the name and load the driver-specific setup DLL. A Setup program calls this function after the driver setup DLL has been installed. The calling program should be aware that this function might not be available for all drivers. In such a case, the calling program should continue without error.

Driver-Specific Options

An application can request driver-specific features exposed by the driver by using the fRequest argument. The fRequest for the first option will be ODBC_CONFIG_DRIVER_MAX+1, and additional options will be incremented by 1 from that value. Any arguments required by the driver for that function should be provided in a null-terminated string passed in the lpszArgs argument. Drivers providing such functionality should maintain a table of driver-specific options. The options should be fully documented in driver documentation. Application writers who use driver-specific options should be aware that this use will make the application less interoperable.

Setting Connection Pooling Timeout

Connection pooling timeout properties can be set when you set the configuration of the driver. SQLConfigDriver is called with an fRequest of ODBC_CONFIG_DRIVER and lpszArgs set to CPTimeout. CPTimeout determines the period of time that a connection can remain in the connection pool without being used. When the timeout expires, the connection is closed and removed from the pool. The default timeout is 60 seconds.

When SQLConfigDriver is called with fRequest set to ODBC_INSTALL_DRIVER or ODBC_REMOVE_DRIVER, the Driver Manager loads the appropriate driver setup DLL and calls the ConfigDriver function. When SQLConfigDriver is called with an fRequest of ODBC_CONFIG_DRIVER, all processing is performed in the ODBC installer, so that the driver setup DLL does not have to be loaded.

Messages

A driver setup routine can send a text message to an application as null-terminated strings in the lpszMsg buffer. The message will be truncated to cbMsgMax minus the null-termination character by the ConfigDriver function if it is greater than or equal to cbMsgMax characters.

For information about See
Adding, modifying, or removing a driver ConfigDriver(in the setup DLL)
Removing the default data source SQLRemoveDefaultDataSource