Question by steviewondrs · Apr 12, 2013 at 02:46 PM · c#dll 64-bit 32bit

x64 dll workaround

As most programmers nowadays only release their SDK's, API's or drivers in an x64 format I was wondering,... actually I really need to find a way to acces a x64 dll from the 32bit Unity platform. (using P-invoke)

I've been researching this problem for quite a while now, and going backwards (from 64 bit to 32 bit) doesn't seem to be a problem. But what if I want to go the other way? Is there some workaround for this problem?

P.S. Pointing out that a x64 Unity editor should be available isn't going to help, because the Unity team is getting pretty nervous about it

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Graham-Dunnett ♦♦ · Apr 12, 2013 at 10:08 PM 0

This is massively outside my area of expertise, but can you write some kind of 32-bit DLL that simply proxies from Unity through to your 64-bit DLL?

steviewondrs · Apr 17, 2013 at 01:02 PM 0

I would have to write CO$$anonymous$$ objects. Or a socket based interface. I think that's way too much work for the few methods I need.

Yokimato · Apr 17, 2013 at 01:17 PM 0

What happens when you try? Bring in the RunTime Interop namespace and declare your methods you're importing to invoke. You might have to adjust IntPtr.Size to 8 when you make your call. I'm interesting in hearing what errors (if any) you get.

A quick not about the pointer size. A pointer (which is basically a reference to a memory location) on 32-bit Windows is stored in 4 bytes i.e 4 x 8 = 32 bits. On 64-bit Windows it’s stored in 8 bytes i.e 8 x 8 = 64 bits.

steviewondrs · Apr 18, 2013 at 07:30 AM 0

DllNotFoundExceptions... But I've tried building the project in x64. I can use the x64 dll when I put it inside the same folder as the .exe that is created. It's a $$anonymous$$or annoyance that I can't use the unity debugger to test my app with the dll, but it works.