BUG: Value of cbDSN in SQLConnect is Not Mapped Correctly (120045)

SYMPTOMS

When connecting from a 16-bit application to a certain 32-bit driver in a Microsoft Windows NT environment, you may receive an error from the driver about incorrect parameter or argument value. This does not happen when SQLConnect is called from a 32-bit application to a 32-bit driver or from a 16-bit application to a 16-bit driver.

For example, assume that the datasource name is "DsnName" with cbDSN=8. Then, the following calls show the behavior:

   //Allocate environment handle
      SQLAllocEnv(phenv);
   //Allocate connection handle
      SQLAllocConnect(henv,phdbc);
   //Specify szDSN="DsnName" and cbDSN= length of ("DsnName")=8
      SQLConnect(hdbc,"DsnName",8,szUID,cbUID,szAuthStr,cbAuthStr);

In looking at the ODBC trace using 32-bit ODBC Spy, you will find that the value of cbDSN passed is not 8, but a large number (0x3a43).

CAUSE

When connecting from a 16-bit application to a 32-bit driver, the value of cbDSN in SQLConnect is not correctly passed and is mapped to a large value. However, the values of cbUID and cbAuthStr are passed correctly.

STATUS

Microsoft has confirmed this to be a problem in ODBC Driver Manager version 2.0. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.