HDF5 documents and links 
Introduction to HDF5 
HDF5 User's Guide 
HDF5 Reference Manual 
HDF5 Application Developer's Guide 

HDF5 Software Changes from Release to Release

This document is designed to help developers maintain HDF5-based applications as they are used with successive releases of HDF5. To that end, this document lists the changes at each release that a maintenance developer needs to be aware of:

Bugfixes and performance enhancements in the C library are automatically picked up by the C++ and Fortran libraries. The Java library will pick up the same bugfixes and enhancements at its next subsequent release as it is always built with the latest released version of the C library.

The release notes also list changes made to the library, but these notes tend to be more at a more detail oriented level. The release notes may include new features, bugs fixed, supported configuration features, platforms on which the library has been tested, and known problems. The release note files are listed below and can be found at the top level of the HDF5 source code tree in the release_docs directory of the distributed HDF5 source code.

RELEASE.txt Technical notes regarding the current release of the HDF5 Library
HISTORY-1_8.txt Technical notes for previous 1.8 releases of the HDF5 Library by release
Technical notes for releases prior to the 1.8.0 release of the HDF5 Library by release

Are you porting an existing application from HDF5 Release 1.6.x to HDF5 Release 1.8.x?
If you are porting an existing application from any HDF5 version in the Release 1.6.x series to any version in the Release 1.8.x series, refer to “What's New in HDF5 1.8.0”. This document, with the documents linked in its introduction, provides a guide to the changes introduced in the transition from the 1.6.x series to HDF5 Release 1.8.0 and discussions of various compatibility issues.

Release 1.8.15 of May 2015 (current release) versus Release 1.8.14

This section lists interface-level changes and other user-visible changes in behavior in the transition from HDF5 Release 1.8.14 to Release 1.8.15.

New and Changed Functions, Classes, Subroutines, Wrappers, and Macros

In the C Interface (main library)
The following new C functions have been added:
Memory allocation functions that use the library’s allocator.

The following functions enable programmatic control of the loading of dynamic plugin filters in user applications:

In the C++ Interface
The following features have been added:
  • New wrappers for the C functions H5Pset_libver_bounds and H5Pget_libver_bounds

    The following wrappers have been added to class H5::FileAccPropList. The first sets the bounds on versions of the HDF5 Library format to be used when creating or writing objects; the second retrieves the current settings:

        void setLibverBounds(H5F_libver_t libver_low, H5F_libver_t libver_high) const;
        void getLibverBounds(H5F_libver_t& libver_low, H5F_libver_t& libver_high) const;
  • New wrappers to retrieve the version of an object header

    The following wrappers have been added to class H5::CommonFG to retrieve the object header version of an object in a file or group, given the object’s name.

        unsigned childObjVersion(const char* objname) const;
        unsigned childObjVersion(const H5std_string& objname) const;
  • A new DataType constructor

    A new DataType constructor takes a PredType object and invokes H5Tcopy to generate another datatype identifier from a predefined datatype.

  • The following features have been changed:
  • Combined H5File::getObjCount overloaded methods

    The following methods:

        ssize_t getObjCount(unsigned types) const;
        ssize_t getObjCount() const;
    have been combined into the following:
        ssize_t getObjCount(unsigned types = H5F_OBJ_ALL) const;
  • Deprecated constructors

    The following two constructors of the classes AbstractDs, IdComponent, H5Location, and H5Object are no longer appropriate after the data member id was moved from IdComponent to the sub-classes in previous releases:

        <Classname>(const hid_t h5_id);
        <Classname>(const <Classname>& original);
    The copy constructors have been no-ops and are removed in this HDF5 Release 1.8.15. The other constructors will be removed in HDF5 Release 1.10 and are expected to be removed from HDF5 Release 1.8.17 if their removal causes no problems.
  • In the Fortran Interface
    The following Fortran 2003 API has been added:

    Operation of the new Fortran 2003 version of this API is more consistent with the operation of the C API than was the Fortran 90 version.
    Users are strongly encouraged to use the Fortran 2003 API.

    Several global variables have been added in the Fortran API. These global variables are equivalent in definition to the comparable C definitions:

    For parallel applications
    A fix for issues encountered upon calling MPI_Finalize without having closed everything in an HDF5 file

    An attribute destroy callback has been attached to MPI_COMM_SELF that shuts down the HDF5 Library when MPI_COMM_SELF is destroyed, that is, on MPI_Finalize. This should fix several issues that users see when they forget to close HDF5 objects before calling MPI_Finalize().

    Compatibility Report and Comments

    Compatibility report for Release 1.8.15 versus Release 1.8.14
    API compatibility report for the HDF5 Library between 1.8.14 and 1.8.15 versions on x86

    Changed shared library interface version number (soname)
    In the C++ interface, two overloaded methods have been combined into a single method and one constructor has been deprecated.

    Due to these changes, the shared library interface version number (soname) has been increased. For a full list of the changed symbols, see the interface compatibility report linked immediately above.

    Prior Releases in the 1.8.x Series

    Change notes for HDF5 Release 1.8.0 to the release immediately preceding the current release are published in “HDF5 Software Changes from Release to Release for HDF5 Releases 1.8.x”.

    Releases 1.6.x and 1.4.x

    Change notes for HDF5 Release 1.6.10 and earlier releases are published in “HDF5 Software Changes from Release to Release for HDF5 Releases 1.4.0 through 1.6.10”.

    HDF5 documents and links 
    Introduction to HDF5 
    HDF5 User's Guide 
    HDF5 Reference Manual 
    HDF5 Application Developer's Guide 

    The HDF Group Help Desk:
    Describes HDF5 Release 1.8.15, May 2015.
      Copyright by The HDF Group
    and the Board of Trustees of the University of Illinois

    Last modified: 12 May 2015