C++ Plugin dev't and DLL files

Unity Engine
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1

Hi,

When a plugin is written (C++, in Visual Studio), and the DLL is created, then the Unity Editor is run, the Editor loads the DLL and never lets it go. That makes it impossible to edit the C++ code in Visual Studio, build, and replace the existing DLL in the Assets/Plugins/… folder because the DLL file is locked. The only way around it is to quit the Editor, compile in Visual Studio, then start the Editor. As you can imagine, this is a pain because 1) The Editor is often slow to start (depending on how many seconds you consider slow), and 2) the unity project takes a while to load as well.

Is there any solution to this? Unity, can you please allow the DLL to be un-loaded so the file can be over-written? Or automatically unload the DLL when the PLAY button is stopped?

Also: Is there a “SEARCH” function in this Unity Forum? I can’t seem to find it anywhere. It would be a pity for people to have to keep asking the same question over and over. Shouldn’t have to rely on Google (only) to find forum postings.

2

There isn’t really a good safe way to unload DLLs. We tried implementing it a while back but with most DLLs it lead to random crashes and hangs. So we decided to scrap this “feature”.

You CAN implement this yourself by loading symbols manually via LoadLibraryW/GetProcAddress P/Invokes, and then unloading it via FreeLibrary.

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