PInvoke restriction: cannot return variants.

[DllExport(CallingConvention = CallingConvention.Cdecl)]
        public static int SetSiteInterface(IntPtr siteInterfacePtr)
        {
            try
            {
                gSite = (SiteInterface)Marshal.PtrToStructure(siteInterfacePtr, typeof(SiteInterface));
            }
            catch(Exception ex)
            {
                
            }
            return 1;
        }

[StructLayoutAttribute(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
    public struct SiteInterface
    {
        public int nStructSize;
        public delegate int GetArraySizeDelegate();
        public GetArraySizeDelegate GetArraySize;
        //C++ TO C# CONVERTER WARNING: C# has no equivalent to methods returning pointers to value types:
        //ORIGINAL LINE: float * (*GetStockArray)(int nType);
        public delegate float GetStockArrayDelegate(int nType);
        public GetStockArrayDelegate GetStockArray;
        public delegate AmiVar GetVariableDelegate(string pszName);
        public GetVariableDelegate GetVariable;
        public delegate void SetVariableDelegate(string pszName, AmiVar newValue);
        public SetVariableDelegate SetVariable;
        public delegate AmiVar CallFunctionDelegate(string szName, int nNumArgs, AmiVar ArgsTable);
        public CallFunctionDelegate CallFunction;
        public delegate AmiVar AllocArrayResultDelegate();
        public AllocArrayResultDelegate AllocArrayResult;
        public delegate object AllocDelegate(uint nSize);
        public AllocDelegate Alloc;
        public delegate void FreeDelegate(object pMemory);
        public FreeDelegate Free;
        public delegate int GetDateTimeArrayDelegate(); // new in 5.30
        public GetDateTimeArrayDelegate GetDateTimeArray;
    }

struct SiteInterface
{
                int         nStructSize;
                int         (*GetArraySize) (void);
                float *     (*GetStockArray)( int nType );
                AmiVar      (*GetVariable) ( const char *pszName );
                void        (*SetVariable) ( const char *pszName, AmiVar newValue );
                AmiVar      (*CallFunction) ( const char *szName, int nNumArgs, AmiVar *ArgsTable );
                AmiVar      (*AllocArrayResult) (void);
                void *      (*Alloc) (unsigned int nSize);
                void        (*Free) (void *pMemory);
                DATE_TIME_INT* (*GetDateTimeArray) (void);    // new in 5.30
};

PLUGINAPI int SetSiteInterface( struct SiteInterface *pInterface )
{
	gSite = *pInterface;

	return TRUE;
}