Question

Given this C API declaration how would it be imported to C#?

const char* _stdcall z4LLkGetKeySTD(void); 

I’ve been able to get this far:

   [DllImport('zip4_w32.dll',        CallingConvention = CallingConvention.StdCall,        EntryPoint = 'z4LLkGetKeySTD',        ExactSpelling = false)]    private extern static const char* z4LLkGetKeySTD(); 

Answer 1

Try this

   [DllImport('zip4_w32.dll',        CallingConvention = CallingConvention.StdCall,        EntryPoint = 'z4LLkGetKeySTD',        ExactSpelling = false)]    private extern static IntPtr z4LLkGetKeySTD(); 

You can then convert the result to a String by using Marshal.PtrToStringAnsi(). You will still need to free the memory for the IntPtr using the appropriate Marshal.Free* method.