ID: Q150151
2.50 WINDOWS kbinterop kbref kbreadme
The information in this article applies to:
Below is the second half of the Microsoft Open Database Connectivity ODBC 2.5 Readme25.txt file, located in the Windows System subdirectory.
NOTE: The first half of the readme25.txt file is located in the following article in the Microsoft Knowledge Base:
ARTICLE-ID: Q150150
TITLE : Contents of ODBC Readme25.txt File (Part 1 of 2)
+++++++++++++++SQLConfigDriver+++++++++++++++
Purpose: SQLConfigDriver loads the appropriate driver setup DLL and calls the ConfigDriver function.
Syntax: BOOL SQLConfigDriver (hwndParent, fRequest, lpszDriver, lpszArgs, lpszMsg, cbMsgMax, pcbMsgOut)
Type Argument Use Description
HWND hwndParent Input Parent window handle.
WORD fRequest Input Type of request. fRequest must
contain one of the following
values:
ODBC_INSTALL_DRIVER:
installing a new driver
ODBC_REMOVE_DRIVER: removing
a driver
This option can also be
driver-specific, in which
case the first option will
be ODBC_CONFIG_DRIVER_MAX+1,
and additional options will
be incremented by 1 from
that value.
LPCSTR lpszDriver Input The name of the driver as
registered in the ODBCINST.INI
key of the registry.
LPCSTR lpszArgs Input A null-terminated string
containing arguments for
a driver-specific fRequest.
LPSTR lpszMsg Output A null-terminated string
containing an output message
from the driver setup.
WORD cbMsgMax Input Length of lpszMsg.
WORD pcbMsgOut Output Total number of bytes
FAR * 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-1.
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 may 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 make use of driver-specific options should be aware that this use will make the application less interoperable.
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-1 characters by the ConfigDriver function if it is greater than or equal to cbMsgMax characters.
+++++++++++++++SQLInstallTranslator+++++++++++++++
Syntax: BOOL SQLInstallTranslator (lpszInfFile, lpszTranslator, lpszPathIn, lpszPathOut, cbPathOutMax, pcbPathOut, fRequest, lpdwUsageCount)
Type Argument Use Description
LPCSTR lpszInfFile Input Full path of the ODBC.INF file
or a null pointer.
If lpszInfFile is a null
pointer, lpszTranslator must
contain a list of keyword-value
pairs describing the
translator.
LPCSTR lpszTranslator Input If lpszInfFile is the path of
the ODBC.INF file, this must
be the key in the ODBC.INF file
that describes the translator.
If lpszInfFile is a null
pointer, this must contain a
list of keyword-value pairs
describing the translator.
The Translator and Setup keywords
have to be included in the
lpszTranslator string. The
translation DLL is listed with
the Translator keyword, and the
translator setup DLL is listed
with the Setup keyword.
LPCSTR lpszPathIn Input Full path of where the
translator is to be installed
or a null pointer. If lpszPath
is a null pointer, then the
translators will be installed
in the System directory.
LPSTR lpszPathOut Output The path of where the translator
should be installed. If the
translator has never been
installed, then lpszPathOut is
the same as lpszPathIn. If
there exists a prior
installation of the translator,
then lpszPathOut is the path of
the prior installation.
WORD cbPathOutMax Input Length of lpszPathOut.
WORD pcbPathOut Output Total number of bytes
FAR * available to return in
lpszPathOut. If the number of
bytes available to return is
greater than or equal to
cbPathOutMax, the output path
in lpszPathOut is truncated to
pcbPathOutMax-1 characters.
WORD fRequest Input Type of request. fRequest must
contain one of the following
values:
ODBC_INSTALL_INQUIRY: inquire
about where a translator can
be installed
ODBC_INSTALL_COMPLETE:
complete the installation
request
translator after this function
has been called.
Comments: SQLInstallTranslator provides a mechanism to install just the translator. This function does not actually copy any files. The calling program is responsible for copying the translator files.
If a version of the translator already exists, but the UsageCount value for the translator does not exist, the new UsageCount value is set to 2.
Length of the Path in lpszPathOut: SQLInstallTranslator allows for a two-phase install process, so an application can determine what cbPathOutMax should be by calling SQLInstallTranslator with an fRequest of ODBC_INSTALL_INQUIRY mode. This will return the total number of bytes available in the pcbPathOut buffer. SQLInstallTranslator can then be called with an fRequest of ODBC_INSTALL_COMPLETE and the cbPathOutMax argument set to the value in the pcbPathOut buffer, plus 1.
If you choose not to use the two-phase model for SQLInstallTranslator, then you must set cbPathOutMax to the value _MAX_PATH, as defined in STDLIB.H, to prevent truncation.
When fRequest is ODBC_INSTALL_COMPLETE, SQLInstallTranslator does not allow lpszPathOut to be NULL (or cbPathOutMax to be 0). If fRequest is ODBC_INSTALL_COMPLETE, FALSE is returned when the number of bytes available to return is greater than or equal to cbPathOutMax, with the result that truncation occurs.
+++++++++++++++SQLRemoveDriver+++++++++++++++
Syntax: BOOL SQLRemoveDriver (lpszDriver, fRemoveDSN, lpdwUsageCount)
Type Argument Use Description
LPCSTR lpszDriver Input The name of the driver as
registered in the ODBCINST.INI
key of the registry.
BOOL fRemoveDSN Input The valid values are:
TRUE Remove DSNs associated
with the driver specified
in lpszDriver.
FALSE Do not remove DSNs
associated with the
driver specified in
lpszDriver.
after this function has been
called.
Comments: SQLRemoveDriver complements the SQLInstallDriver function, and updates the UsageCount. This function does not actually remove any files. The calling program is responsible for deleting files.
SQLRemoveDriver will decrement the UsageCount value by 1. If the UsageCount goes to 0, then the following will occur:
1. SQLConfigDriver with the ODBC_REMOVE_DRIVER option will be called. If the fRemoveDSN option is set to TRUE, the ConfigDSN function calls SQLRemoveDSNFromIni to remove all the data associated with the driver specified in lpszDriver. 2. The driver registry entry itself will be removed.
+++++++++++++++SQLRemoveDriverManager+++++++++++++++
Syntax: BOOL SQLRemoveDriverManager (lpdwUsageCount)
Type Argument Use Description
Manager after this function
has been called.
Comments: SQLRemoveDriverManager complements the SQLInstallDriverManager function, and updates the UsageCount. This function does not remove any files. The calling program is responsible for deleting files.
SQLRemoveDriverManager will decrement the UsageCount value of the ODBC core components by 1. If the UsageCount goes to 0, then the ODBC core component registry entry will be removed.
+++++++++++++++SQLRemoveTranslator+++++++++++++++
Syntax: BOOL SQLRemoveTranslator (lpszTranslator, lpdwUsageCount)
Type Argument Use Description
LPCSTR lpszTranslator Input The name of the translator as
registered in the ODBCINST.INI
key of the registry.
translator after this function
has been called.
Comments: If the UsageCount goes to 0, then the translator?s registry entry will be removed. This function does not remove any files. The calling program is responsible for properly removing the translator files.
+++++++++++++++MODIFIED INSTALLER FUNCTIONS+++++++++++++++
SQLConfigDataSource
SQLCreateDataSource
SQLGetPrivateProfileString
SQLInstallDriver
SQLInstallDriverManager
SQLInstallODBC
SQLManageDataSources
SQLWritePrivateProfileString
+++++++++++++++SQLConfigDataSource+++++++++++++++
Type Argument Use Description
HWND hwndParent Input Parent window handle. The
function will not display any
dialog boxes if the handle is
null.
WORD fRequest Input Type of request. fRequest must
contain one of the following
values:
ODBC_ADD_DSN: Add new user data
source.
ODBC_CONFIG_DSN: Modify an
existing data source.
ODBC_REMOVE_DSN: Remove an
existing data source.
ODBC_ADD_SYS_DSN: Add a new
system data source.
ODBC_CONFIG_SYS_DSN: Modify
an existing system data
source.
ODBC_REMOVE_SYS_DSN: Remove
an existing system data
source.
LPCSTR lpszDriver Input Driver description (usually the
name of the associated DBMS)
presented to users instead of
the physical driver name.
LPCSTR lpszAttributes Input List of attributes in the form
of keyword-value pairs. For
more information, see ConfigDSN
in the Microsoft ODBC 2.10
Programmer's Reference.
SQLConfigDataSource maps the system DSN fRequests to the user DSN fRequests (ODBC_ADD_SYS_DSN to ODBC_ADD_DSN, ODBC_CONFIG_SYS_DSN to ODBC_CONFIG_DSN, and ODBC_REMOVE_SYS_DSN to ODBC_REMOVE_DSN). To distinguish user and system DSNs, SQLConfigDataSource sets the wSystemDSN state variable according to the following table. Prior to returning, SQLConfigDataSource resets wSystemDSN to BOTHDSN.
fRequest wSystemDSN
ODBC_ADD_DSN USERDSN_ONLY
ODBC_CONFIG_DSN USERDSN_ONLY
ODBC_REMOVE_DSN USERDSN_ONLY
ODBC_ADD_SYS_DSN SYSTEMDSN_ONLY
ODBC_CONFIG_SYS_DSN SYSTEMDSN_ONLY
ODBC_REMOVE_SYS_DSN SYSTEMDSN_ONLY
+++++++++++++++SQLCreateDataSource+++++++++++++++
The System DSN check box is displayed whenever the SQLCreateDataSource function is called to display the Add Data Source dialog box, except when this dialog box is displayed through the Control Panel. In this case, a data source is added either from the Data Sources dialog box (for user data sources) or from the System Data Sources dialog box, so the System DSN check box is not needed.
+++++++++++++++SQLGetPrivateProfileString+++++++++++++++
+++++++++++++++SQLInstallDriver+++++++++++++++
+++++++++++++++SQLInstallDriverManager+++++++++++++++
+++++++++++++++SQLInstallODBC+++++++++++++++
1. Increment the component usage count of the ODBC core components. 2. Increment the component usage count of the drivers being installed. 3. Increment the component usage count of the translators being installed. 4. Increment the file usage count of each file being installed. 5. Modify the FileList key with the appropriate files (see the File Count Tracking section of this readme for more information).
Note that SQLInstallODBC is the only one of the ODBC installer functions that actually copies files. SQLInstallODBC does not support the Uninstall process. If an application's setup program uses SQLInstallODBC, the application will not be Windows 95 logo compliant.
SQLInstallODBC performs the same functions as SQLInstallDriverManager, SQLInstallDriver, SQLConfigDriver (with ODBC_INSTALL_DRIVER), and SQLInstallTranslator. SQLInstallODBC does not perform the functions accomplished by SQLRemoveTranslator, SQLConfigDriver (with SQL_REMOVE_DRIVER), SQLRemoveDriver, and SQLRemoveDriverManager).
SQLInstallODBC should incorporate the removal functions, and so support Uninstall and Windows 95 logo compliance, in ODBC 3.0.
+++++++++++++++SQLManageDataSources+++++++++++++++
+++++++++++++++SQLWritePrivateProfileString+++++++++++++++
SECTION 3: ODBC FUNCTION CHANGES
The following changes have been made to the ODBC functions documented in the ODBC 2.10 Programmer's Reference and SDK Guide.
+++++++++++++++REBINDING WITH SQLBindCol+++++++++++++++
+++++++ATTEMPTING TO ADD TRUNCATED DATA WITH SQLSetPos+++++++
Using SQLSetPos with an fOption of SQL_ADD to add data from a buffer that was truncated when bound by a call to SQLBindCol, will result in a General-Protection Fault. Prior to calling SQLSetPos with an fOption of SQL_ADD, application writers should verify that the value pointed to by pcbValue in the accompanying call to SQLBindCol is not greater than cbValueMax.
+++++++++++++++pcbValue IN SQLBindParameter+++++++++++++++
SQLExecDirect, SQLExecute, and SQLPutData return SQLSTATE 07S01 (Invalid use of default parameter) when a parameter value was set to SQL_DEFAULT_PARAM, and the corresponding parameter was not a parameter for an ODBC canonical procedure invocation.
+++++++++++++SQLSTATE S1C00 RETURNED BY SQLPrepare+++++++++++++
SQLPrepare will return SQLSTATE S1C00 (Driver not capable) if the cursor/concurrency combination is invalid.
+++SQLSTATE 22005 RETURNED BY SQLExtendedFetch and SQLFetch+++
SQLExtendedFetch and SQLFetch will return SQLSTATE 22005 (Error in assignment) if a zero-length string was inserted into a string field, and the field was bound to a numeric data type, so the string was converted to a zero.
+++SQLSTATE 22008 RETURNED BY SQLExtendedFetch and SQLFetch+++
SQLExtendedFetch and SQLFetch will return SQLSTATE 22008 (Datetime field overflow) if a SQL_C_TIME, SQL_C_DATE, or SQL_C_TIMESTAMP value was converted to a SQL_CHAR data type, and the value was, respectively, an invalid date, time, or timestamp.
++++++++++++SQLSTATE 22012 RETURNED BY SQLGetData++++++++++++
SQLGetData will return SQLSTATE 22012 (Division by zero) if a value from an arithmetic expression was returned that resulted in division by zero.
+++++++++++CURSOR CONCURRENCY SET IN SQLSetStmtOption++++++++++
The default value for SQL_CONCURRENCY is SQL_CONCUR_READ_ONLY. This option can also be set through the fConcurrency argument in SQLSetScrollOptions. This option cannot be specified for an open cursor.
If the SQL_CURSOR_TYPE fOption is changed to a type that does not support the current value of SQL_CONCURRENCY, the value of SQL_CONCURRENCY is not automatically changed to a supported value, and no error will be reported until SQLExecDirect or SQLPrepare is called.
If the driver supports the SELECT_FOR_UPDATE statement, and such a statement is executed while the value of SQL_CONCURRENCY is set to SQL_CONCUR_READ_ONLY, an error will be returned. If the value of SQL_CONCURRENCY is changed to a value that the driver supports for some value of SQL_CURSOR_TYPE, but not for the current value of SQL_CURSOR_TYPE, the value of SQL_CURSOR_TYPE is not automatically changed to a supported value, and no error will be reported until SQLExecDirect or SQLPrepare is called.
++++++++++++++ERROR MESSAGE FORMAT+++++++++++++
++++++++++++++NOTES TO DRIVER WRITERS+++++++++++++
To make sure the compiler doesn't assign ordinal values for non-exported functions, include the "PROTMODE" statement in the definition (.DEF) file that describes the dynamic-link library. For more information, see "Building Drivers: Use of PROTMODE Line in .DEF Files" in the ODBC SDK Knowledge Base Help file.
2. An application might occasionally invoke a driver connection while responding to a DDE Initiate request from another application. If the driver displays a connect dialog box and yields to Windows, it may cause unpredictable system behavior. Therefore, drivers must call InSendMessage before displaying any dialog or message boxes to see if they are being called while the application is in SendMessage processing. If so, only SYSTEM MODAL dialogs are permitted so that Windows can block additional messages being sent to the applications.
Drivers that support the asynchronous mode of ODBC operations MUST not rely upon windows PeekMessage functionality to emulate such support. This also applies to ALL underlying components (network libraries, any asynchronous DDEML based drivers, underlying data access components, and so on). Any ODBC application that implements asynchronous ODBC operations may show unexpected behavior and cause the entire Windows system to become unstable, if such a driver was used. Therefore, driver writers must make sure that implementation of asynchronous mode does not yield control to Windows.
3. For driver-specific options (>999), the thunking layer checks to see if vParam is a valid pointer. If it is not, vParam is passed unchanged as a 32-bit integer. In the case where an application expects vParam to be an integer, and the value for vParam happened to be a valid pointer, the driver will receive an invalid 32-bit integer value.
In addition, if a driver tries to return a pointer in the pvParam argument of SQLGetStmtOption for a driver-specific option, it will not be translated. Instead of passing back a pointer, the driver should copy the associated value back into the calling application's buffer.
Additional reference words: 2.50 VFoxWin FoxPro Excel Access Word Visual Basic VB readme.txt KBCategory: kbinterop kbref kbreadme KBSubcategory: FxinteropOdbc
Keywords : FxinteropOdbc
Version : 2.50
Platform : WINDOWSLast Reviewed: September 9, 1997