[Gretl-users] Error 12 calling gretl_read_native_data

Hello gretl users! I'm trying to open a ".gdt" file calling gretl_read_native_data (system info's: "gretl 1.9.6 - build date 2011-10-17" on "Windows 7 Ultimate - Service Pack 1") from a C# class: the result is always an error code 12 (it seems that something is wrong into the file path name ...). Follows a significant excerpt of my code [Start C# code] ... IntPtr dset; [DllImport(@"C:\Program Files (x86)\gretl\libgretl.dll")] internal static extern void libgretl_init(); [DllImport(@"C:\Program Files (x86)\gretl\libgretl.dll")] internal static extern IntPtr create_new_dataset(IntPtr pZ, int nvar, int nobs, int markers); [DllImport(@"C:\Program Files (x86)\gretl\libgretl.dll", CharSet = CharSet.Unicode)] internal static extern int gretl_read_native_data(string fname, IntPtr pdset); ... int err; string fname = @"C:\Program Files (x86)\gretl\data\misc\australia.gdt"; libgretl_init(); dset = datainfo_new(); err = gretl_read_native_data(fname, dset); ... [End C# code] Where am I wrong? Regards, Filippo.