# What’s new in h5py 3.11

## New features

- h5py is now compatible with Numpy 2.0 (PR 2329, PR 2401).

- New methods `Group.visit_links()` and `Group.visititems_links()` that include links when visiting groups (PR 2360).

## Exposing HDF5 functions

- Exposes remaining information from H5O_info_t struct such as access, modification, change, and birth time (PR 2358). Also exposes field providing number of attributes attached to an object. Expands object header metadata struct H5O_hdr_info_t, hdr field of H5O_info_t, to provide number of chunks and flags set for object header. Lastly, adds meta_size field from H5O_info_t struct that provides two fields, attr which is the storage overhead of any attached attributes, and obj which is storage overhead required for chunk storage. The last two fields added can be useful for determining the storage overhead incurred from various data layout/chunked strategies, and for obtaining information such as that provided by h5stat.

## Bug fixes

- h5py’s tests pass with HDF5 1.14.4, which is due to be released shortly after h5py 3.11 (PR 2406).

- `iter_chunks()` now behaves correctly with a selection (PR 2381).

- HDF5 allows external datasets (with the data stored in a separate file) to be expandable along the first dimension. Such datasets can now be created through h5py by passing a `maxshape=` parameter (PR 2398).

## Building h5py

- h5py can now be built with Cython 3.x (PR 2345).

- Fixed some errors compiling with GCC 14 (PR 2380, PR 2382).