HDF5-1.10.5 Release (Newsletter #168) - The HDF Group

The HDF5-1.10.5 release is now available for download from:


The user documentation and source code (only) can be obtained from the Support Portal:


This release contains several important new features and changes:

  • Support for OpenMPI was added. For known problems and issues please see OpenMPI Build Issues.
  • To better support OpenMPI, all MPI-1 API calls were replaced by MPI-2 equivalents.
  • Support was added for cross compiling with CMake on HPC machines.
  • A new option was added to enable/disable using pread/pwrite in place of read/write in the sec2, log, and core VFDs:
    Autotools: --enable-preadwrite
  • The ability to minimize dataset object headers was added. New APIs (for C, Fortran, and Java) were introduced to support this feature. See: H5Fget_dset_no_attrs_hint, H5Fset_dset_no_attrs_hint, H5Pget_dset_no_attrs_hint and H5Pset_dset_no_attrs_hint.
  • New chunk query functions (for C) were added. See: H5Dget_chunk_info, H5Dget_chunk_info_by_coord, and H5Dget_num_chunks.
  • The macros for the H5Oget_info and H5Ovisit APIs were removed and the H5Oget_info*1 and H5Ovisit*1 APIs were copied to H5Oget_info* and H5Ovisit*. As an example, H5Oget_info and H5Oget_info1 are identical in this release. API compatibility for maintenance releases was broken in HDF5-1.10.3 (and 1.10.4) when these macros were introduced, and this change corrects that.
  • To improve performance, the default behavior changed when reading a contiguous dataset collectively in its entirety by all processes.
  • Several bugs were fixed, including CVE vulnerability issues, as well as hanging issues with collective metadata reads during chunked dataset I/O, found in netCDF-4.

For details regarding these and other changes, please see the Release Notes. Also see Software Changes from Release to Release.

Congratulations HDF5ers!

Delphi bindings are available in
hdf5dll.pas (248.7 KB)

along with generator script:
hdf5pas.py (29.2 KB)


  • More complete comments;
  • Bindings for stock H5FD*.h file drivers.

Best wishes,
Andrey Paramonov