Problem:
Which directory do I put UDF DLLs?

Solution:
InterBase uses the Win32 API function: LoadLibrary to load a UDF.

Here is the order that the Operating System will use to try and load the DLL:
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1. The directory from which the application is loaded. 

2. The current directory. 

3. Windows 95: The Windows system directory. Use the GetSystemDirectory 
    function to get the path of this directory. 

    Windows NT: The 32-bit Windows system directory. Use the GetSystemDirectory
    function to get the path of this directory. The name of this directory is SYSTEM32. 

4. Windows NT: The 16-bit Windows system directory. There is no Win32 function
    that obtains the path of this directory, but it is searched. The name of this directory 
    is SYSTEM. 

5. The Windows directory. Use the GetWindowsDirectory function to get the path 
     of this directory. 

6. The directories that are listed in the PATH environment variable. 

7. The lib directory.