Hmmm.  

Must be rather old since it mentions 16-bit Windows but not 64-bit Windows.  So 
for all the parts that reference the "System" directories you need to apply a 
grain of salt....

64-bit Windows looks for 64-bit DLLs in Windows\System32
64-bit Windows looks for 32-bit DLLs in Windows\SysWOW64 (and not in 
Windows\System32)
32-bit Windows looks for 32-bit DLLs in Windows\System32
32-bit Windows looks for 16-bit DLLs in Windows\System

The "Common Files" search location is automagically, on 64-bit Windows,
Program Files (x86)\Common Files when looking for at 32-bit DLL and
Program Files\Common Files when looking for 64-bit DLL

Similarly the names for 32-bit versions of Windows searching for 32-bit DLLs is
Program Files\Common Files

Also, searches that search the "Program Files" tree will automatically use 
"Program Files (x86)" tree if looking for 32-bit DLLs on 64-bit Windows
Other search locations in the AppData tree also magically redirect to the (x86) 
directories if looking for 32-bit DLLs on 64-bit Windows

Paths are not modified so you better hope that if you put the DLL in a 
directory in the (various) paths that it will attempt to load ONLY THE FIRST 
such DLL found and will crash (or the loader will fail) if the DLL first found 
is the wrong "bitedness".  There are sekret registry hacks that you can do to 
register the "same" module in different locations for 16/32/64 loading 
automagically (more or less) but those hacks are not officially supported.

So, if you are using multiple versions of the same module named DLL, you have 
to be careful where you put it, unless you know that you will only ever require 
one model, or the application itself loads the DLL from the Application 
Directory.  Otherwise, if you need multiple models simultaneously you need to 
be careful where you put them of use the default System directories.

---
The fact that there's a Highway to Hell but only a Stairway to Heaven says a 
lot about anticipated traffic volume.


>-----Original Message-----
>From: sqlite-users [mailto:sqlite-users-
>boun...@mailinglists.sqlite.org] On Behalf Of Warren Young
>Sent: Tuesday, 10 October, 2017 08:57
>To: SQLite mailing list
>Subject: Re: [sqlite] SQLite3 on Windows
>
>On Oct 10, 2017, at 3:49 AM, Phoenix <rwm.phoe...@btinternet.com>
>wrote:
>>
>> 2) Does the .dll need to be in a specific folder or is it okay if
>the
>> folder is listed in my PATH?
>
>https://msdn.microsoft.com/en-
>us/library/windows/desktop/ms682586(v=vs.85).aspx
>
>_______________________________________________
>sqlite-users mailing list
>sqlite-users@mailinglists.sqlite.org
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