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 intended to assist application developers who must keep an application synchronized with the HDF5 library or related software.

Release 1.6.0 (current release) versus Release 1.4.5

This section lists the API-level changes that have been made in the transition from the HDF5 Release 1.4.x series to Release 1.6.0.

New Functions and Tools

The following functions are new for Release 1.6.0 and are included in the HDF5 Reference Manual.

`H5Dget_offset`	hsize_t `H5Dget_offset` (hid_t `dset_id`)
`H5Dget_space_status`	hid_t `H5Dget_space_status` (hid_t `dset_id`, H5D_space_status_t *`status`)
`H5Fget_obj_ids`	int `H5Fget_obj_ids` (hid_t `file_id`, unsigned int `types`, int `max_objs`, hid_t *`obj_id_list`)
`H5Fget_vfd_handle`	herr_t `H5Fget_vfd_handle` (hid_t `file_id`, hid_t `fapl_id`, void *`file_handle`)
`H5Gget_num_objs`	herr_t `H5Gget_num_objs` (hid_t `loc_id`, hsize_t* `num_obj`)
`H5Gget_objname_by_idx`	ssize_t `H5Gget_objname_by_idx` (hid_t `group_id`, hsize_t `idx`, char `name`, size_t `size`)
`H5Gget_objtype_by_idx`	int `H5Gget_objtype_by_idx` (hid_t `group_id`, hsize_t `idx`)
`H5Iget_name`	ssize_t `H5Iget_name` (hid_t `obj_id`, char `name`, size_t* `size`)
`H5Pall_filters_avail`	htri_t `H5Pall_filters_avail` (hid_t `dcpl_id`)
`H5Pfill_value_defined`	herr_t `H5Pfill_value_defined` (hid_t `plist_id`, H5D_fill_value_t *`status`)
`H5Pget_alloc_time`	herr_t `H5Pget_alloc_time` (hid_t `plist_id`, H5D_alloc_time_t *`alloc_time`)
`H5Pget_edc_check`	H5Z_EDC_t `H5Pget_edc_check` (hid_t `plist`)
`H5Pget_family_offset`	herr_t `H5Pget_family_offset` (hid_t `fapl_id`, hsize_t *`offset`)
`H5Pget_fapl_mpiposix`	herr_t `H5Pget_fapl_mpiposix` (hid_t `fapl_id`, MPI_Comm *`comm`)
`H5Pget_fill_time`	herr_t `H5Pget_fill_time` (hid_t `plist_id`, H5D_fill_time_t *`fill_time`)
`H5Pget_filter_by_id`	herr_t `H5Pget_filter_by_id` (hid_t `plist_id`, H5Z_filter_t `filter`, unsigned int `flags`, size_t `cd_nelmts`, unsigned int `cd_values[]`, size_t `namelen`, char *`name[]`)
`H5Pget_hyper_vector_size`	herr_t `H5Pget_hyper_vector_size` (hid_t `dxpl_id`, size_t *`vector_size`)
`H5Pget_multi_type`	herr_t `H5Pget_multi_type` (hid_t `fapl_id`, H5FD_mem_t *`type`)
`H5Pmodify_filter`	herr_t `H5Pmodify_filter` (hid_t `plist`, H5Z_filter_t `filter`, unsigned int `flags`, size_t `cd_nelmts`, const unsigned int `cd_values[]`)
`H5Pset_alloc_time`	herr_t `H5Pset_alloc_time` (hid_t `plist_id`, H5D_alloc_time_t `alloc_time`)
`H5Pset_edc_check`	herr_t `H5Pset_edc_check` (hid_t `plist`, H5Z_EDC_t `check`)
`H5Pset_family_offset`	herr_t `H5Pset_family_offset` (hid_t `fapl_id`, hsize_t `offset`)
`H5Pset_fapl_mpiposix`	herr_t `H5Pset_fapl_mpiposix` (hid_t `fapl_id`, MPI_Comm `comm`)
`H5Pset_fill_time`	herr_t `H5Pset_fill_time` (hid_t `plist_id`, H5D_fill_time_t `fill_time`)
`H5Pset_filter`	herr_t `H5Pset_filter` (hid_t `plist`, H5Z_filter_t `filter`, unsigned int `flags`, size_t `cd_nelmts`, const unsigned int `cd_values[])`
`H5Pset_filter_callback`	herr_t `H5Pset_filter_callback` (hid_t `plist`, H5Z_filter_func_t `func`, void *`op_data`)
`H5Pset_fletcher32`	herr_t `H5Pset_fletcher32` (hid_t `plist`)
`H5Pset_hyper_vector_size`	herr_t `H5Pset_hyper_vector_size` (hid_t `dxpl_id`, size_t `vector_size`)
`H5Pset_multi_type`	herr_t `H5Pset_multi_type` (hid_t `fapl_id`, H5FD_mem_t `type`)
`H5Pset_shuffle`	herr_t `H5Pset_shuffle` (hid_t `plist_id`)
`H5Pset_szip`	herr_t `H5Pset_szip` (hid_t `plist`, unsigned int `options_mask`, unsigned int `pixels_per_block`)
`H5Rget_object_type`	int `H5Rget_object_type` (hid_t `id`, void *`ref`)
`H5set_free_list_limits`	herr_t `H5set_free_list_limits` (int `reg_global_lim`, int `reg_list_lim`, int `arr_global_lim`, int `arr_list_lim`, int `blk_global_lim`, int `blk_list_lim`)
`H5Sget_select_type`	H5S_sel_type `H5Sget_select_type` (hid_t `space_id`)
`H5Tdetect_class`	htri_t `H5Tdetect_class` (hid_t `dtype_id`, H5T_class_t `dtype_class`)
`H5Tget_native_type`	hid_t `H5Tget_native_type` (hid_t `type_id`, H5T_direction_t `direction`)
`H5Tis_variable_str`	htri_t `H5Tis_variable_str` (hid_t `dtype_id`)
`H5Zfilter_avail`	herr_t `H5Zfilter_avail` (H5Z_filter_t `filter`)
`H5Zunregister`	herr_t `H5Zunregister` (H5Z_filter_t `filter`)

The following tools are new for Release 1.5 and are included in the HDF5 Reference Manual.

h5diff

h5import

h5fc

h5c++

h5perf

h5redeploy

Deleted Functions

The following functions are deprecated in HDF5 Release 1.6.0. A backward compatibility mode is provided in this release, enabling these functions and other Release 1.4.x compatibility features, but is available only when the HDF5 library is configured with the flag H5_WANT_H5_V1_4_COMPAT. The backward compatibility mode is not enabled in the binaries distributed by NCSA.

H5Pset_hyper_cache
H5Pget_hyper_cache

H5Rget_object_type

The above functions will eventually be removed from the HDF5 distribution and from the HDF5 Reference Manual.

Functions with Changed Syntax

The following functions have changed as noted.

C functions:
H5FDflush and VFL "flush" callbacks: An extra parameter closing has been added to these functions, to allow the library to indicate that the file will be closed following the call to "flush". Actions in the "flush" call that are duplicated in the VFL "close" call may be omitted by the VFL driver.
* H5Gget_objtype_by_idx: The function return type has changed from int to the enumerated type H5G_obj_t.
* H5Pset(get)_buffer: The size parameter for H5Pset_buffer has changed from type hsize_t to size_t.; The H5Pget_buffer return type has similarly changed from hsize_t to size_t.
* H5Pset(get)_cache: The rdcc_nelmts parameter has changed from type int to size_t.
* H5Pset_fapl_log: The verbosity parameter has been removed.; Two new parameters have been added: flags of type unsigned and buf_size of type size_t.
* H5Pset(get)_fapl_mpiposix: A use_gpfs parameter of type hbool_t has been added.
* H5Pset(get)_sieve_buf_size: The size parameter has changed from type hsize_t to size_t.
* H5Pset(get)_sym_k: The lk parameter has changed from type int to unsigned.
* H5Sget_select_bounds: The start and end parameters have changed from type hsize_t * to hssize_t * to better match the rest of the dataspace API.
* H5Zregister: This function is substantially revised in Release 1.6.0 with a new H5Z_class_t struct and new set local and can apply callback functions.

Fortran90 functions:
h5pset(get)_fapl_core_f: The backing_store parameter has changed from INTEGER to LOGICAL to better match the C API.
h5pset(get)_preserve_f: The flag parameter has changed from INTEGER to LOGICAL to better match the C API.

Backward compatibility with the Release 1.4.x syntax is available for the functions indicated above with a leading asterisk (*). The backward compatibility features are available only when the HDF5 library is configured with the flag H5_WANT_H5_V1_4_COMPAT, is not enabled in the binaries distributed by NCSA, and will eventually be removed from the HDF5 distribution.

Constants with Changed Values

Release 1.4.5 versus Release 1.4.4

C Library

Added functions:

herr_t H5Pset_fapl_mpiposix(hid_t fapl_id, MPI_Comm comm);
herr_t H5Pget_fapl_mpiposix(hid_t fapl_id, MPI_Comm *comm/*out*/);

Changed functions: The following functions have changed behavior.

H5Pset_fapl_mpio
H5Pget_fapl_mpio
H5Fcreate
H5Fopen
H5Fclose Previously, the Communicator and Info object arguments supplied to H5Pset_fapl_mpio were stored in the property with its handle values. This meant changes to the communicator or the Info object after calling H5Pset_fapl_mpio would affect the how the property list functioned. This was also the case when H5Fopen/create operated. They just stored the handle value. This is not according to the MPI-2 defined behavior of how Info objects should be handled. (MPI-2 defines Info objects must be parsed when called.)
H5Pset_fapl_mpio now stores a duplicate of each of the communicator and Info object.
H5Pget_fapl_mpio now returns a duplicate of its stored communicator and Info object. It is now the responsibility of the applications to free those objects when done.
H5Fcreate and H5Fopen also store a duplicate of the communicator and Info object supplied by the file access property List. H5Fclose frees the duplicates.
Advice to users: User applications should release the communicator and Info object returned by H5Pget_fapl_mpio when they are no longer needed.

Removed functions:

None

There were no other public API changes in the C library for this release.

Fortran90 Library

The following missing Fortran functions were added:

h5get_libversion_f, h5check_version_f, h5garbage_collect_f, h5dont_atexit_f
h5tget_member_index_f, h5tvlen_create_f
h5dget_storage_size_f, h5dvlen_get_max_len_f , h5dwrite_vl_f, h5dread_vl_f

Only integer, real and character types are supported for VL datatypes.

Release 1.4.4 versus Release 1.4.3

C Library

Added functions:

H5Pget_small_data_block_size
H5Pset_small_data_block_size
H5Tget_member_index

Changed functions:

None

Removed functions:

None

There were no other public API changes in the C library for this release.

Fortran90 Library

h5dwrite_f, h5dread_f, h5awrite_f, h5aread_f were overloaded with dims argument to be assumed size array of type INTEGER(HSIZE_T). We recommend to use the subroutines with the new type. Module subroutines that accept dims as INTEGER array of size 7 will be deprecated in the 1.6.0 release.

Release 1.4.3 versus Release 1.4.2

C Library

Removed function:

H5Pset_fapl_dpss

There were no other public API changes in the C library for this release.

Fortran90 Library

There were no changes to the public Fortran90 APIs for this release.

Release 1.4.2 versus Release 1.4.1

C Library

The HDF5 Release 1.4.2 C library is a "Bugfix Release"; there are no API changes in the underlying HDF5 library.

Fortran90 Library

The following functions in the HDF5 Release 1.4.2 Fortran90 library have an additional parameter, dims, that was not present in Release 1.4.1:

h5aread_f(attr_id, memtype_id,  buf, dims, hdferr)
h5awrite_f(attr_id, memtype_id,  buf, dims, hdferr)
h5dread_f(dset_id, mem_type_id, buf, dims, hdferr, mem_space_id, &
           file_space_id, xfer_prp)
h5dwrite_f(dset_id, mem_type_id, buf, dims, hdferr, mem_space_id, &
           file_space_id, xfer_prp)

The dims parameter enables library portability between the UNIX and Microsoft Windows platforms.

Release 1.4.1 versus Release 1.4.0

Release 1.4.1 is a "Tools Release"; there are no API changes in the underlying HDF5 library.

Release 1.4.0 versus Release 1.2.2

Several functions were added to or removed from the HDF5 library in the development of Release 1.4.0. A few functions have been modified in minor ways.

New Functions

The following functions are new for Release 1.4.0 and are included in the HDF5 Reference Manual.

herr_t H5Dvlen_get_buf_size (hid_t dataset_id, hid_t type_id, 
           hid_t space_id, hsize_t *size);
herr_t H5Epush (const char *file, const char *func,
           unsigned line, H5E_major_t maj, H5E_minor_t min, 
           const char *str);
hid_t H5Pget_driver (hid_t plist_id);
void *H5Pget_driver_info (hid_t plist_id);
herr_t H5Pget_dxpl_mpio (hid_t dxpl_id, 
           H5FD_mpio_xfer_t *xfer_mode/*out*/);
herr_t H5Pget_dxpl_multi (hid_t dxpl_id, 
           hid_t *memb_dxpl/*out*/);
herr_t H5Pget_fapl_core (hid_t fapl_id, size_t *increment/*out*/,
           hbool_t *backing_store/*out*/) 
herr_t H5Pget_fapl_family (hid_t fapl_id, 
           hsize_t *memb_size/*out*/, hid_t *memb_fapl_id/*out*/);
herr_t H5Pget_fapl_mpio (hid_t fapl_id, MPI_Comm *comm/*out*/,
           MPI_Info *info/*out*/);
herr_t H5Pget_fapl_multi (hid_t fapl_id, 
           H5FD_mem_t *memb_map/*out*/, hid_t *memb_fapl/*out*/, 
           char **memb_name/*out*/, haddr_t *memb_addr/*out*/, 
           hbool_t *relax/*out*/);
herr_t H5Pget_fapl_stream (hid_t fapl_id,
           H5FD_stream_fapl_t *fapl /*out*/ );
herr_t H5Pget_meta_block_size (hid_t fapl_id, 
           hsize_t *size/*out*/);
herr_t H5Pget_sieve_buf_size (hid_t fapl_id, 
           hsize_t *size/*out*/);
herr_t H5Pset_driver (hid_t plist_id, hid_t driver_id,
           const void *driver_info);
herr_t H5Pset_dxpl_mpio (hid_t dxpl_id, 
           H5FD_mpio_xfer_t xfer_mode);
herr_t H5Pset_dxpl_multi (hid_t dxpl_id, 
           const hid_t *memb_dxpl);
herr_t H5Pset_fapl_core (hid_t fapl_id, size_t increment, 
           hbool_t backing_store)
herr_t H5Pset_fapl_family (hid_t fapl_id, hsize_t memb_size,
           hid_t memb_fapl_id);
herr_t H5Pset_fapl_log (hid_t fapl_id, char *logfile, 
           int verbosity);
herr_t H5Pset_fapl_mpio (hid_t fapl_id, MPI_Comm comm, 
           MPI_Info info);
herr_t H5Pset_fapl_multi (hid_t fapl_id, 
           const H5FD_mem_t *memb_map, const hid_t *memb_fapl, 
           const char **memb_name, const haddr_t *memb_addr, 
           hbool_t relax);
herr_t H5Pset_fapl_sec2 (hid_t fapl_id);
herr_t H5Pset_fapl_split (hid_t fapl, const char *meta_ext,
           hid_t meta_plist_id, const char *raw_ext,
           hid_t raw_plist_id);
herr_t H5Pset_fapl_stdio (hid_t fapl_id);
herr_t H5Pset_fapl_stream (hid_t fapl_id,
           H5FD_stream_fapl_t *fapl);
herr_t H5Pset_meta_block_size(hid_t fapl_id, hsize_t size);
herr_t H5Pset_sieve_buf_size(hid_t fapl_id, hsize_t size);
hid_t H5Tarray_create (hid_t base, int rank, const hsize_t dims[], 
           const int perm[])
int H5Tget_array_dims (hid_t adtype_id, hsize_t *dims[], int *perm[])
int H5Tget_array_ndims (hid_t adtype_id)

The following functions are new for Release 1.4.0, but are intended only for use in specialized environments. These are also included in the HDF5 Reference Manual.

herr_t H5Pget_fapl_dpss (hid_t fapl_id);
herr_t H5Pget_fapl_gass (hid_t fapl_id, GASS_Info *info/*out*/);
herr_t H5Pget_fapl_srb (hid_t fapl_id, SRB_Info *info);
herr_t H5Pset_fapl_dpss (hid_t fapl_id);
herr_t H5Pset_fapl_gass (hid_t fapl_id, GASS_Info info);
herr_t H5Pset_fapl_srb (hid_t fapl_id, SRB_Info info);

The following functions are new for Release 1.4.0 but are intended only for driver development work, not for general use. They are listed in the List of VFL Functions document in the HDF5 Technical Notes. They are described in detail only in the source code and do not appear in the HDF5 Reference Manual.

haddr_t H5FDalloc (H5FD_t *file, H5FD_mem_t type, 
          hsize_t size);
herr_t H5FDclose (H5FD_t *file);
int H5FDcmp (const H5FD_t *f1, const H5FD_t *f2);
herr_t H5FDflush (H5FD_t *file);
herr_t H5FDfree (H5FD_t *file, H5FD_mem_t type, 
          haddr_t addr, hsize_t size);
haddr_t H5FDget_eoa (H5FD_t *file);
haddr_t H5FDget_eof (H5FD_t *file);
H5FD_t *H5FDopen (const char *name, unsigned flags, 
          hid_t fapl_id, haddr_t maxaddr);
int H5FDquery (const H5FD_t *f, unsigned long *flags);
herr_t H5FDread (H5FD_t *file, hid_t dxpl_id, haddr_t addr, 
          hsize_t size, void *buf/*out*/);
haddr_t H5FDrealloc (H5FD_t *file, H5FD_mem_t type, 
          haddr_t addr, hsize_t old_size, hsize_t new_size);
hid_t H5FDregister (const H5FD_class_t *cls);
herr_t H5FDset_eoa (H5FD_t *file, haddr_t eof);
herr_t H5FDunregister (hid_t driver_id);
herr_t H5FDwrite (H5FD_t *file, H5FD_mem_t type, 
          hid_t dxpl_id, haddr_t addr, hsize_t size, 
          const void *buf);

Deleted Functions

The following functions have been removed from the HDF5 library and from the HDF5 Reference Manual.

H5Pget_core
H5Pget_driver
H5Pget_family
H5Pget_mpi
H5Pget_sec2
H5Pget_split
H5Pget_stdio
H5Pget_xfer

H5Pset_core
H5Pset_family
H5Pset_mpi
H5Pset_sec2
H5Pset_split
H5Pset_stdio
H5Pset_xfer

H5RAclose
H5RAcreate
H5RAopen
H5RAread
H5RAwrite
H5Tget_member_dims
H5Tinsert_array

Note that the entire H5RA interface, an experimental interface for ragged arrays, has been removed from the library.

Functions with Changed Syntax

The following functions have changed slightly.

H5Pget_buffer: Return type has changed to hsize_t.
H5Pset_buffer: The type of the size parameter has changed to hsize_t.
H5Tconvert: The type of the nelmts parameter has changed to hsize_t.

Constants with Changed Values

The values of the constants H5P_DEFAULT and H5S_ALL have been changed from -2 to 0. These default values had to be special-cased in situations where they could be returned to distinguish them from error values.

Migration from Release 1.2.2 to Release 1.4.x

H5Tinsert_array

The functionality of H5Tinsert_array has been replaced by H5Tarray_create. Here is an example of changing code from H5Tinsert_array to H5Tarray_create.

V1.2.2
{
    struct tmp_struct {
        int a;
        float f[3];
        double d[2][4];
    };
    size_t f_dims[1]={3};
    size_t d_dims[2]={2,4};
    hid_t compound_type;

    compound_type=H5Tcreate(H5T_COMPOUND,sizeof(struct tmp_struct));
    H5Tinsert(compound_type,"a",HOFFSET(struct tmp_struct,a),H5T_NATIVE_INT);
    H5Tinsert_array(compound_type,"f",HOFFSET(struct tmp_struct,f),1,f_dims,NULL,H5T_NATIVE_FLOAT);
    H5Tinsert_array(compound_type,"d",HOFFSET(struct tmp_struct,d),2,d_dims,NULL,H5T_NATIVE_DOUBLE);
}

V1.4.0
{
    struct tmp_struct {
        int a;
        float f[3];
        double d[2][4];
    };
    hsize_t f_dims[1]={3};
    hsize_t d_dims[2]={2,4};
    hid_t compound_type;
    hid_t array_type;

    compound_type=H5Tcreate(H5T_COMPOUND,sizeof(struct tmp_struct));
    H5Tinsert(compound_type,"a",HOFFSET(struct tmp_struct,a),H5T_NATIVE_INT);
    array_type=H5Tarray_create(H5T_NATIVE_FLOAT,1,f_dims,NULL);
    H5Tinsert(compound_type,"f",HOFFSET(struct tmp_struct,f),array_type);
    H5Tclose(array_type);
    array_type=H5Tarray_create(H5T_NATIVE_DOUBLE,2,d_dims,NULL);
    H5Tinsert(compound_type,"d",HOFFSET(struct tmp_struct,d),array_type);
    H5Tclose(array_type);
}

This and Prior Releases: The RELEASE.txt and HISTORY.txt Files

The HDF5 source code, as distributed to users and developers, contains two files that will be of interest to readers of this document. Both files are located at the top level of the source code tree and are duplicated here for your reference:

RELEASE.txt

Technical notes regarding the release, including new features and the changes since the last release, notes regarding new or revised utilities, notes regarding alternative language APIs (Fortran90, C++), bugs fixed since the last release, platforms on which the release has been tested, and known problems. This is the file commonly known as "the release notes."

HISTORY.txt

A release-by-release history of the HDF5 library. This file is a compiled set of the release notes (i.e., the RELEASE.txt files) from prior releases.

HDF5 documents and links
Introduction to HDF5

HDF5 User's Guide
HDF5 Reference Manual
HDF5 Application Developer's Guide

HDF Help Desk
Describes HDF5 Release 1.6.0, July 2003

Last modified: 2 July 2003