anchor.diff:    nativeFile: Pointer;
     err: bson_error_t;
   begin
  +  FillChar(err, SizeOf(bson_error_t), 0);
     nativeFile := mongoc_gridfs_find_one_cnv_by_filename(FNativeGridfs,
                                                          PAnsiChar(AName),
                                                          @err, FlagsToNative(AFlags));
     if nativeFile = nil then
  -    raise EMongoGridfs.Create(@err);
  +    RaiseFindFileError(@err);
   
     Result := NewMongoGridfsFile(nativeFile);
   end;
  
positive.code:   end;
  end;
  
  procedure TMongoGridfs.RemoveFile(const AName: UTF8String);
  begin
    if not mongoc_gridfs_remove_by_filename(FNativeGridfs, PAnsiChar(AName),
  
negative.code:                                            query.NativeBson, @err,
                                             FlagsToNative(AFlags));
    if nativeFile = nil then
      RaiseFindFileError(@err);
  
    Result := NewMongoGridfsFile(nativeFile);
  end;
  