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cwindowsinterop64-bit32bit-64bit

Can we invoke functions of a DLL compiled for 64 bit using an application compiled for 32 bit?

Can we invoke functions of a DLL compiled for 64 bit using an application compiled for 32 bit?

I am using Windows 2008 64 bit system. But, the application is still compiled using 32 bit.

The code involves MFC & Windows SDK functions.

Solution

  • No. A 32-bit application cannot load a 64-bit module into its process space (nor vice versa).

    Remember that 32-bit processes are only supported on 64-bit versions of Windows in the dedicated Windows-on-Windows (WOW64) subsystem. That makes interoperability tricky at best. Raymond Chen's blog entry on the subject is quite instructive, if you care about the technical details.

    You will either need to recompile one or the other, or load it into a separate process and use interprocess communication to coordinate between the two.