H5Ovisit2

herr_t H5Ovisit2(hid_t obj_id,  H5_index_t idx_type,  H5_iter_order_t order,
       H5O_iterate1_t op,  void *  op_data,  uint  fields)

Visits objects (version 2, deprecated).

`obj_id`	Object identifier
`idx_type`	Index type
`order`	Iteration order
`op`	Callback function
`op_data`	User data for callback
`fields`	Fields to retrieve (H5O_INFO flags)

Return value from callback, or negative on failure.