Exiting a 16-bit application that uses .NET

Question

Hi,

 

Our company still has to support legacy products written in 16-bit (MSVC 1.52).  We "thunk" from 16 to 32-bit very often without any issue.

Recently, I have felt the need to use the nice features/classes offered by .NET and so I would load and unload (via LoadLibrary and FreeLibrary) a VC++ CLR enabled dll that will make use of .NET classes .  All works nice except when I exit my 16-bit application "hosted" under ntvdm, the 32-bit CLR dll that made use of .NET seemingly stays in memory and I cannot rename the folder from which my 16-bit app was running from as a result.

The function FreeLibrary does return true and no matter how simplistic my usage of .NET classes may be, I cannot get it to release my folder.  If I choose to make my 16-bit app to run in a separate memory space (shortcut option) then I am able to rename my folder but I want to know if there is a different solution than this workaround.

 

Thanks.

 

Answer 1

Stop Win16. It is deprecated.

We are in post 32bit era, we are in the Win64 world/

So migrate your Win16 app to Win32.

regards,

Christophe PICHAUD

MCSD, MCSD.NET, MCTS NET 2.0

www.christophep.com

 

 

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Christophe Pichaud

Answer 2

Are you using .Net 4 or earlier?

 

Answer 3

For this particular project, I am currently using .NET 3.5 and VS2008.  However, the whole project will be merged and "migrated" into another that uses .NET 4.0 and VS2010 after the new year.

 

Thanks.

Answer 4

It's a wild guess, but have you tried rebuilding your dll in .Net 4?

.Net versions before 4 are "sticky" in that once a process loads them, they can't really be unloaded. That's one of the reasons why the Microsoft MSI group did not recommend creating custom actions in .Net.

 

Answer 5

I have just tried; Unfortunately, that was not it.  As soon as I make my VC++ project "/CLR" even without any assembly reference, the problem arises.

Thank you for the idea anyways.