HDF5 Software Changes from Release to Release
for HDF5 Releases 1.8.x

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

Library Configuration

Compatibility Notes and Report

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

Compatibility Report and Comments

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

Compatibility Report and Comments

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

Other New Features

Command-line Tools with Changed Behavior

Removed Functions and Wrappers

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

New Command-line Tool Options and Option Parameters

Build and Configuration

Compile Scripts with Changed Behavior

Command-line Tools with Changed Behavior

New and Changed Functions and Subroutines

New Feature: Dynamically Loaded Filters

New Command-line Tool Option

New Configuration and Build Tool

Function, Subroutines, and Feature with Changed Syntax or Behavior

Command-line Tools with Changed Behavior

Removed Functions and Wrappers

New and Changed Functions and Subroutines

Changed Command-line Tool

New and Changed Functions

A new high level C function and Fortran subroutine were added to HDF5 Lite (H5LT) to determine whether an HDF5 path is correct and resolves to a valid HDF5 object:

• H5LTpath_valid
• h5ltpath_valid_f

The new file image operations feature consists of the following functions and their associated callbacks, struct, and ENUM. This feature enables an application to load a file into memory (as a file image) and to operate on that file image without the overhead of disk I/O. This feature provides the following functions:

H5LTopen_file_image H5Fget_file_image
H5Pset_file_image H5Pget_file_image		H5Pset_file_image_callbacks H5Pget_file_image_callbacks

For the callbacks, struct, and ENUM, see H5Pset_file_image_callbacks.

Use of this feature is described in “HDF5 File Image Operations” (PDF).
 

The following functions were modified or added to the HDF5 Library to allow an application to control the operation of copying committed datatypes with H5Ocopy:

Function with changed interface:

• H5Pset_copy_object

New flag for use with H5Pset_copy_object:

• H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG

Function with changed behavior:

• H5Ocopy
  This function’s behavior is changed, but only with the use of the new flag, H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG.

New functions and callback function:

H5Pset_mcdt_search_cb H5Pget_mcdt_search_cb H5O_mcdt_search_cb_t

H5Padd_merge_committed_dtype_path H5Pfree_merge_committed_dtype_paths

Use of this capability is described in “Copying Committed Datatypes with H5Ocopy” (PDF).
 

The following C functions and Fortran subroutines were added to provide a mechanism to ensure sequential consistency in parallel environments using MPI I/O:

H5Fset_mpi_atomicity H5Fget_mpi_atomicity

h5fset_mpi_atomicity_f h5fget_mpi_atomicity_f

Use of this capability is described in “Enabling a Strict Consistency Semantics Model in Parallel HDF5” (PDF).
 

The following function was added at Release 1.8.5 but was not documented at that time. It is mentioned here for those who may have missed its introduction:

• H5Oexists_by_name

New Fortran Subroutines

The following Fortran subroutines have been added in this release:

• h5ltpath_valid_f
• h5ocopy_f
• h5fset_mpi_atomicity_f
• h5fget_mpi_atomicity_f

Where a subroutine is part of a new HDF5 feature, that feature is described above.

Fortran Subroutine with Changed Behavior

The content of the buffer returned by the following Fortran subroutine has changed as noted:

• h5ltget_attribute_string_f
  If the returned buffer requires padding, h5ltget_attribute_string_f now employs space padding; this buffer was previously returned with a C NULL terminator.

Command-line Utilities with New Options and/or Changed Behavior

h5repack has one new option and improved performance under certain circumstances:

• ‐Mn, ‐‐metadata_block_size=n
  Sets the metadata block size in the output file.
   
• Performance is improved when repacking large chunked datasets (for example, when dataset size exceeds 128 MB).

 

h5stat has one new option:

• ‐S, ‐‐summary
  Displays a summary of file space usage for a file.

 

h5dump has one new option, a new capability, and updated output:

• ‐‐no-compact-subset
  Disables compact subsetting to allow the left-hand square bracket character ( [ ) in a dataset name.
   
• The files parameter now accommodates wildcards. With this change, h5dump command-line options can be applied across multiple files without listing the files individually.
   
• h5dump output has been updated for this release to improve compliance with the HDF5 DDL specification and to improve readablilty. This output is now fully compliant with the HDF5 DDL specification, but these changes may affect some user scripts:
  • Whitespace has been modified.
  • Display errors, such as misplaced brackets, have been fixed.
  • When printing superblock content, user block content is now properly displayed within the superblock.

New C Functions

Two new parallel I/O functions enable an application to query whether or how a collective I/O operation actually completed:

• H5Pget_mpio_actual_chunk_opt_mode
• H5Pget_mpio_actual_io_mode

Updated Fortran Interface, including Fortran 2003 Features

The HDF5 Fortran interface has been extended and upgraded to Fortran 2003 for this release.

See “Configure and Build Changes” below for the configure options to use when building HDF5 with Fortran 2003 enabled.

Features enabled in this upgrade are described in New Features in the HDF5 Fortran Library: Adding Support for the Fortran 2003 Standard (PDF only). In general, the links below are to technical descriptions (reference manual entries, for example) of specific interfaces.

Terminology: If the Fortran compiler in use is Fortran 2003 compliant and the installed HDF5 Library was configured using both the --enable-fortran and --enable-fortran2003 flags, the resulting HDF5 Fortran Library is referred to below as a Fortran 2003 environment. Without either of the Fortran 2003 compliant compiler or the --enable-fortran2003 flag, the resulting HDF5 Fortran Library is referred to below as a Fortran 90 environment.

New Fortran 2003-only subroutines
New subroutines available only in Fortran 2003 environments:

• h5dvlen_reclaim_f
• h5eset_auto_f
• h5literate_by_name_f
• h5literate_f
• h5ovisit_f
• h5oget_info_by_name_f
• h5tconvert_f

Subroutines with Fortran 90 versions and extended features in Fortran 2003 environments
Subroutines in this section have extended support in Fortran 2003 environments, but are new or unchanged in Fortran 90 environments.

All existing Fortran 90 subroutines, including those not mentioned below, are available in both Fortran 90 and Fortran 2003 environments.

Subroutines with support for the derived type C_PTR in Fortran 2003 environments:

• h5pget_f
• h5pget_fill_value_f
• h5pinsert_f
• h5pregister_f
• h5pset_f
• h5pset_fill_value_f
• h5rcreate_f
• h5rdereference_f
• h5rget_name_f
• h5rget_object_type_f

Subroutines with support for the derived type C_PTR and a changed signature in Fortran 2003 environments:

• h5aread_f
• h5awrite_f
• h5dread_f
• h5dwrite_f

Subroutine with additional optional parameters in Fortran 2003 environments:

• h5pcreate_class_f

New and updated Fortran 90 subroutines
New Fortran 90 subroutines:

• h5pset_nbit_f
• h5pset_scaleoffset_f

Updated Fortran 90 subroutines:

• h5open_f
• h5close_f *
• h5check_version_f
• h5get_libversion_f
• h5garbage_collect_f
• h5dont_atexit_f

* h5close_f has been modified in this release to close only the HDF5 Fortran Library interface; it no longer closes the underlying HDF5 Library.

New Fortran utility functions and derived types
New Fortran utility functions:

• h5offsetof         Available only in Fortran 2003 environments.
• h5kind_to_type     Available in either Fortran environment.

New Fortran derived types in Fortran 2003 environments:

• hvl_t              Described in New Features.
• h5o_info_t         See h5ovisit_f.

New high level Fortran interface
New Fortran subroutines in the HDF5 Dimension Scale high-level interface, H5DS:

• h5dsset_scale_f
• h5dsattach_scale_f
• h5dsdetach_scale_f
• h5dsis_attached_f
• h5dsis_scale_f
• h5dsset_label_f
• h5dsget_label_f
• h5dsget_scale_name_f
• h5dsget_num_scales_f

These subtroutines are available in both Fortran 90 and Fortran 2003 environments.

C Functions with Changed Capability

H5Tcreate now supports fixed-length and variable-length string types.

Driver Changes on Windows Systems

Command-line Utilities with Changed Behavior

Configure and Build Changes

Parallel Library and Configuration Changes

New C Functions and Macros

Three new functions enable the caching of files opened through external links. This cache can improve the performance of external links in heavy use cases:

• H5Pset_elink_file_cache_size
• H5Pget_elink_file_cache_size
• H5Fclear_elink_file_cache

 
Two new macros enable compile-time inclusion or exclusion of code depending on the version of the HDF5 Library against which an application is to be linked:

• H5_VERSION_GE
• H5_VERSION_LE

C Functions with Changed Capability

HDF5 now allows the size of any dataspace dimension to be 0 (zero). This was previously allowed only if the maximum size of the dimension was unlimited. Though their signatures have not changed, the range of valid parameter values is affected for the following functions:

• H5Screate_simple
• H5Sset_extent_simple
• H5Pset_external

Note that no data can be written to a dataset in which the size of any dimension is set to zero.
 
In the logging file driver, implementation of the following flags has been completed: H5FD_LOG_TIME_OPEN, H5FD_LOG_TIME_READ, H5FD_LOG_TIME_WRITE, and H5FD_LOG_TIME_SEEK
Two new flags have been added: H5FD_LOG_NUM_TRUNCATE and H5FD_LOG_TIME_STAT.

• H5Pset_fapl_log

 
HDF5 now blocks committing a datatype that cannot hold any data. This currently includes compound datatypes with no fields and enumerated datatypes with no members.

• H5Tcommit1
• H5Tcommit2
• H5Tcommit_anon

HDF5 has long blocked creating a dataset or attribute with such a datatype.

Fortran Subroutines with Changed Capability

Several h5ltmake_dataset*_f and h5ltread_dataset*_f subroutines have been modified to allow them to create or read arrays of up to seven dimensions. They had previously been limited to three dimensions.

h5ltmake_dataset_f h5ltmake_dataset_int_f h5ltmake_dataset_float_f h5ltmake_dataset_double_f

h5ltread_dataset_f h5ltread_dataset_int_f h5ltread_dataset_float_f h5ltread_dataset_double_f

 
h5tbget_field_info_f has a new maxlen_out parameter. This parameter is optional.

Command-line Utilities with New Options

h5diff has a new verbose with levels option to display additional attribute information:

• -vn, --verbose=n

 
h5dump has one new option to enable reporting of the HDF5 Library’s error stack:

• --enable-error-stack

Command-line Utility with Changed Option Name

h5ls has one changed option name:

• --enable-error-stack replaces --error.

The --error option is deprecated but remains available.

Command-line Utilities with Changed Behavior

Configure and Build Changes

Parallel HDF5

C Functions with Additional Capability

H5Tset_order and H5Tget_order can now be used with all datatypes. See the related note regarding H5T_ORDER_MIXED immediately below.

ENUM with New Member

H5T_order_t, an ENUM used to set or indicate datatype endianness, includes a new member:

     H5T_ORDER_MIXED

The function H5Tget_order returns this value when called on a compound datatype whose members are not all of the same endianness.

Command-line Utilities with New Options

h5diff has one new option:

• --exclude-path

h5ls and h5diff have two new options:

• --follow-symlinks
• --no-dangling-links

Command-line Utilities with Changed Behavior

Compiler Script Arguments and Environment Variables

        $CLINKER 
        $H5BLD_CPPFLAGS 
        $CPPFLAGS 
        $H5BLD_CFLAGS 
        $CFLAGS 
        $LDFLAGS 
        $clibpath 
        $link_objs 
        $LIBS 
        $link_args 
        $shared_link
            

Thread Safety on Windows

Parallel HDF5

New C Function

The following function was added to the HDF5 Library at this release, but was not documented at that time:

• H5Oexists_by_name

(This note added in November 2011, shortly following Release 1.8.8.)

C Functions with Additional Capability

The following functions have been modified to accommodate filters set on a group creation property list:

H5Pall_filters_avail H5Pget_filter1 H5Pget_filter2 H5Pget_filter_by_id1 H5Pget_filter_by_id2 H5Pget_nfilters

H5Pmodify_filter H5Premove_filter H5Pset_deflate H5Pset_filter H5Pset_fletcher32

Related to H5Zregister, the calling protocol for the can_apply and set_local callback functions has been extended to accommodate the use of filters on group creation property lists.

New C++ Member Function and Overloaded Member Functions

The following C++ member function is new in this release:

DataSet::getInMemDataSize

To simplify getting a dataset’s data size in memory.

The overloaded forms of the following C++ member functions are new in this release:

CommonFG::getObjnameByIdx		Overloaded to take char* for name.
CommonFG::getObjTypeByIdx		Overloaded to return type name as a char*.

Command-line Utility with New Options

h5diff has two new options:

• --follow-links
• --no-dangling-links

Fortran Subroutines with Changed Interface

The link type parameter values associated with the following Fortran subroutines have changed in this release:

• h5lget_info_f
• h5lget_info_by_idx_f

Valid values for the parameter link_type have changed to the following:
     H5L_TYPE_HARD_F
     H5L_TYPE_SOFT_F
     H5L_TYPE_EXTERNAL_F
     H5L_TYPE_ERROR_F
These values previously began with the string 'H5L_LINK_'.

CMake

This release includes an adaptation enabling HDF5 builds with CMake. This early-stage adaptation is distributed to provide an opportunity for early access and experimentation; the CMake-related files should not be viewed as final and may change before the next release.

While the initial development effort has been focussed on Microsoft Windows platforms, the HDF5 Library has been successfully built with CMake on Linux and Mac OS X.

See the file CMake.txt in the distributed HDF5 source code (hdf5/release_docs/CMake.txt) for details.

Embedded HDF5 Library Settings Information

Library settings are now embedded in an HDF5 executable so that an “orphaned” executable can be queried (via the Unix strings command, for example) to display the library settings used to build it. The embedded settings information is the same as that normally found in the libhdf5.settings file.

This capability may be disabled with the use of the --disable-embedded-libinfo flag during configure.

New Fortran Subroutine and Constant

The following Fortran subroutine is new in this release: h5oopen_by_addr_f

The following Fortran constant, corresponding to the C constant H5T_ORDER_NONE, has been added in this release: H5T_ORDER_NONE_F

New C++ Member Functions

New C++ member functions are provided to determine a dataset’s or attribute’s data size in memory: size_t DataSet::getInMemDataSize() const
size_t Attribute::getInMemDataSize() const The size in each case is in bytes.

Function with Changed Interface or Behavior

H5check_version now displays embedded library information (see above) if a version mismatch is detected.

The function has also been changed to suppress the warning message entirely if $HDF5_DISABLE_VERSION_CHECK is set to 2 or higher.

Fortran Subroutines with Changed Syntax

The following Fortran subroutines have changed syntax in this release:

• h5lget_info_f

The type of the parameter address has changed from INTEGER to INTEGER(HADDR_T).
(This note added on 13 January 2010.)

• h5lget_info_by_idx_f
h5lget_info_by_idx_f (loc_id, group_name, index_field, order, n, &
     link_type, f_corder_valid, corder, cset, address, val_size, &
     hdferr, lapl_id)

The parameters link_type, address, and val_size have been added; the parameter data_size has been removed.

Tools with Changed Interface or Behavior

h5diff has one new option: --use-system-epsilon

With this option, h5diff returns a difference if and only if the difference between two data values exceeds the system value for epsilon (that is, if |a-b| > epsilon).

The tool’s default behavior has also changed; without this option, the tool now checks for strict equality. Prior default behavior was to use an epsilon internally defined in HDF5.

This option has no short form.

h5dump has one new option and the behavior of another set of options has changed: -R or --region

With this option, h5dump prints the data pointed to by a region reference. Without this option, h5dump prints only the reference.

Usage of the subsetting parameters has changed. All of START, STRIDE, COUNT, and BLOCK now have default values. If those defaults are satisfactory, h5dump no longer requires that all four be specifiespecified when subsetting a dataset.

Changed Library Configuration

The following configuration flag is new with this release: --disable-embedded-libinfo This flag disables the embedding of HDF5 Library settings in an HDF5 executable.

New Functions

C functions:

The following C functions are new for this release and are documented in the HDF5 Reference Manual.

	H5Pset_elink_cb		herr_t H5Pset_elink_cb( hid_t lapl_id, H5L_elink_traverse_t func, void *op_data ) See entry.
	H5Pget_elink_cb		herr_t H5Pget_elink_cb( hid_t lapl_id, H5L_elink_traverse_t *func, void **op_data ) See entry.
	H5Pset_elink_acc_flags		herr_t H5Pset_elink_acc_flags( hid_t lapl_id, unsigned flags ) See entry.
	H5Pget_elink_acc_flags		herr_t H5Pget_elink_acc_flags( hid_t lapl_id, unsigned *flags ) See entry.
	H5Pset_chunk_cache		herr_t H5Pset_chunk_cache( hid_t dapl_id, size_t rdcc_nslots, size_t rdcc_nbytes, double rdcc_w0 ) See entry.
	H5Pget_chunk_cache		herr_t H5Pget_chunk_cache( hid_t dapl_id, size_t *rdcc_nslots, size_t *rdcc_nbytes, double *rdcc_w0 ) See entry.
	H5Dget_access_plist		hid_t H5Dget_access_plist( hid_t dset_id ) See entry.
	H5Iis_valid		htri_t H5Iis_valid( hid_t id ) See entry.

Fortran Subroutines:

The following subroutines are new in this release: h5dget_access_plist_f  
h5iis_valid_f  
h5pset_chunk_cache  
h5pget_chunk_cache  

Function with Changed Behavior

H5set_free_list_limits

The HDF5 Library now dynamically creates separate factory free lists to manage blocks of a fixed size; these blocks were previously managed within the blockfree lists. Factory free lists use the same settings as specified in H5set_free_list_limits for block free lists.

While the API has not changed, users may see both a performance boost and increased memory usage.

Tools with Changed Interface or Behavior

h5diff

The default behavior of h5diff is now to detect and compare NaNs. Use the -N or --nan option (below) to turn this behavior off and avoid the performance penalty that NaN detection and comparison entalis. (NaN detection and comparison became the default in in HDF5 Release 1.6.8.)

This tool has two new options:

     -c, --compare      Lists objects that are not comparable.

     -N, --nan          Avoids NaNs detection.

h5dump

h5dump now correctly specifies an XML DTD or a schema URL.

h5dump binary output now defaults to NATIVE.

The new -b, --binary option can be used to specify alternate binary formats.

h5repack

When a user does not specify a chunk size, h5repack now defines the default chunk size to be the same same as the size of the hyperslab used to read the chunks.

New Functions

C functions:

The following C functions are new for this release and are documented in the HDF5 Reference Manual.

	H5Pset_elink_fapl		herr_t H5Pset_elink_fapl( hid_t lapl_id, hid_tfapl_id ) See entry.
	H5Pget_elink_fapl		hid_t H5Pget_elink_fapl( hid_t lapl_id ) See entry.

Fortran Subroutine:

The following subroutine is new in this release:
     H5Tget_native_type_f

New C++ Wrappers

The following functions were added as wrappers for the C function H5Rdereference to replace the incorrect IdComponent::dereference():

        void H5Object::dereference(H5Object& obj, void* ref, 
                                   H5R_type_t ref_type=H5R_OBJECT)
        void H5Object::dereference(H5File& h5file, void* ref, 
                                   H5R_type_t ref_type=H5R_OBJECT)
        void H5Object::dereference(Attribute& obj, void* ref, 
                                   H5R_type_t ref_type=H5R_OBJECT)
                

The following constructors were added to create the associated objects by way of dereference:

        DataSet(H5Object& obj, void* ref, H5R_type_t ref_type=H5R_OBJECT)
        DataSet(H5File& file, void* ref, H5R_type_t ref_type=H5R_OBJECT)
        DataSet(Attribute& attr, void* ref, H5R_type_t ref_type=H5R_OBJECT)
        Group(H5Object& obj, void* ref, H5R_type_t ref_type=H5R_OBJECT)
        Group(H5File& obj, void* ref, H5R_type_t ref_type=H5R_OBJECT)
        Group(Attribute& attr, void* ref, H5R_type_t ref_type=H5R_OBJECT)
        DataType(H5Object& obj, void* ref, H5R_type_t ref_type=H5R_OBJECT)
        DataType(H5File& file, void* ref, H5R_type_t ref_type=H5R_OBJECT)
        DataType(Attribute& attr, void* ref, H5R_type_t ref_type=H5R_OBJECT)
                

Functions with Changed Syntax

C functions:

H5Fget_obj_count

ssize_t H5Fget_obj_count( hid_t file_id, unsigned int types )

H5Fget_obj_ids

ssize_t H5Fget_obj_ids( hid_t file_id, unsigned int types,
        size_t max_objs, hid_t *obj_id_list )

Changed Fortran Subroutines

The optional parameter mounted has been added to the following subroutines:

h5gget_info_f
h5gget_info_by_idx_f
h5gget_info_by_name_f     

Changed Data Structure

H5G_info_t

A mounted filed has been added to the H5G_info_t struct.

Tools with Changed Interface or Behavior

h5diff

h5diff now returns 1 if the files differ in structure, i.e., if the file graphs differ by any object.

The tool’s error return code has been changed to 2.

h5repack and h5diff

The standard command-line syntax of both tools has been changed to parallel that of h5dump. The new syntax of each is as follows:

     h5repack [OPTIONS] file1 file2

     h5diff [OPTIONS] file1 file2 [object1 [object2]]

In each case, the old syntax remains available (though undocumented) to avoid breaking existing scripts.

h5repack

The following new options control the addition of user block data to an existing HDF5 file:

-u U --ublock=U		Specifies the name of the file containing the user block data to be added.
-b B --block=B		Specifies the size of the block to be added.

The following new options set parameters governing the tool’s use of H5Pset_alignment:

-t T --threshold=T		Specifies the threshold value for H5Pset_alignment.
-a A --alignment=A		Specifies the alignment value for H5Pset_alignment.

h5repack now supports multiple instances of the '-f' or '--filter' option, allowing the use of multiple I/O filters with an object.

With no change in the command-line syntax, h5repack now retains an existing userblock when repacking an HDF5 file.

h5import

The floating point format flag TEXTFPE, for scientific notation, has been deprecated. The flag TEXTFP, which accepts scientific notation, should be used instead.

h5import now imports string data with the STR keyword in the INPUT-CLASS configuration field.

h5dump and h5ls

These tools now traverse external links when performing recursive traversals.

h5dump

Binary output now defaults to NATIVE with the '-b' option, optionally accepting NATIVE, FILE, BE, and LE.

The new '-m T' or '--format T' option enables a user-defined formatting string for printing floating-point numbers.

With no change in the command-line syntax, h5dump now prints a compression ratio when compression filters are in use.

Deprecated Functions

        H5Pset_preserve
        H5Pget_preserve 

The original role of these functions is now part of the core HDF5 Library functionality.

Changed File Installation

Changed Library Configuration

Note that if an SZIP library path is set in a user-supplied LD_LIBRARY_PATH, in an existing script, for example, that does not necessarily need to be changed; configure will prepend the SZIP library path extracted from --with-szlib to the user-supplied LD_LIBRARY_PATH.

The most significant new feature is an expanded set of Fortran90 APIs, enabling essentially all new C library features of Release 1.8.0.

New Functions and Tools

C functions:

There are no new C functions for Release 1.8.1.

Fortran subroutines:

The following Fortran subroutines are new for Release 1.8.1 and are documented in the HDF5 Reference Manual.

H5A h5acreate_f h5acreate_by_name_f h5adelete_by_idx_f h5adelete_by_name_f h5aexists_f h5aexists_by_name_f h5aget_create_plist_f h5aget_info_f h5aget_info_by_idx_f	h5aget_info_by_name_f h5aget_name_by_idx_f h5aget_storage_size_f h5aopen_f h5aopen_by_idx_f h5aopen_by_name_f h5arename_f h5arename_by_name_f
H5D h5dcreate_anon_f h5dcreate_f	h5dopen_f h5dset_extent_f
H5G h5gcreate_anon_f h5gcreate_f h5gget_create_plist_f h5gget_info_f	h5gget_info_by_idx_f h5gget_info_by_name_f h5gopen_f
H5L h5lcopy_f h5lcreate_external_f h5lcreate_hard_f h5lcreate_soft_f h5ldelete_f h5ldelete_by_idx_f	h5lexists_f h5lget_info_f h5lget_info_by_idx_f h5lget_name_by_idx_f h5lmove_f
H5O h5olink_f	h5oopen_f
H5P h5pget_attr_creation_order_f h5pget_attr_phase_change_f h5pget_char_encoding_f h5pget_copy_object_f h5pget_create_inter_group_f h5pget_data_transform_f h5pget_elink_prefix_f h5pget_est_link_info_f h5pget_fapl_direct_f h5pget_link_creation_order_f h5pget_link_phase_change_f h5pget_local_heap_size_hint_f h5pget_nlinks_f h5pget_obj_track_times_f h5pget_shared_mesg_index_f h5pget_shared_mesg_nindexes_f	h5pset_attr_creation_order_f h5pset_attr_phase_change_f h5pset_char_encoding_f h5pset_copy_object_f h5pset_create_inter_group_f h5pset_data_transform_f h5pset_elink_prefix_f h5pset_est_link_info_f h5pset_fapl_direct_f h5pset_libver_bounds_f h5pset_link_creation_order_f h5pset_link_phase_change_f h5pset_local_heap_size_hint_f h5pset_obj_track_times_f h5pset_nbit_f h5pset_nlinks_f h5pset_scaleoffset_f
H5R h5rget_name_f
H5S h5sdecode_f h5sencode_f	h5sextent_equal_f
H5T h5tcommit_anon_f h5tcommit_f h5tcommitted_f h5tcompiler_conv_f	h5tdecode_f h5tencode_f h5tget_create_plist_f h5topen_f

C++ wrappers:

There are no new C++ wrappers for Release 1.8.1.

Functions and Tools with Changed Syntax

C functions with changed syntax:

There are no C functions with changed syntax in Release 1.8.1.

Fortran subroutines with changed syntax:

In the following Fortran subroutines, spos is a new parameter indicating the position of the sign bit:
     h5tset_fields_f(type_id, spos, epos, esize, mpos, msize, hdferr)
     h5tget_fields_f(type_id, spos, epos, esize, mpos, msize, hdferr)

Changed C++ wrappers:

• The class AbstractDS was moved out of H5Object.

  The class Attribute now multiply inherits from IdComponent and AbstractDs; the class DataSet now multiply inherits from H5Object and AbstractDs.

  In addition, data member IdComponent::id was moved into subclasses: Attribute, DataSet, DataSpace, DataType, H5File, Group, and PropList.

• IdComponent::dereference was incorrect; it was changed from:
     void IdComponent::dereference(IdComponent& obj, void* ref)
to:
     void H5Object::dereference(H5File& h5file, void* ref)
     void H5Object::dereference(H5Object& obj, void* ref)

Tools with changed syntax:

• The command-line syntax of h5repack was changed in Release 1.8.0 to the following:
       h5repack [OPTIONS] in_file out_file

  Since this would be imcompatible with existing user scripts, the original syntax has be re-enabled in this release:
       h5repack -i in_file -o out_file [OPTIONS]

  h5repack now understands either syntax.

• An h5repack option to set the minimum number of links in indexed format was introduced in Release 1.8.0 as '-d min_indexed_links' or '--indexed=min_indexed_links'. In Release 1.8.1, the '-i' form has been changed to '-d' as follows:
       -d min_indexed_links
  or
       --indexed=min_indexed_links

• The command-line syntax of h5diff was changed in Release 1.8.0 to the following:
       h5diff [OPTIONS] file1 file2 [object1 [object2 ] ]

Tools with new options:

• h5dump -m T  or  --format T   Sets format of floating point output
  

Changed Behavior or Output

Changed library behavior:

A 4GB limit on the size of dataset chunks is now properly enforced when a dataset is created.

The HDF5 Library now works more effectively with external links. Some valid external links that previously failed will now be properly recognized. See H5Lcreate_external.

C functions with changed behavior:

The behavior of H5Lcreate_external has changed as described immediately above.

Tools with changed behavior and changed output:

The h5dump -p option now prints the compression ratio if a compression filter is associated with a dataset.

h5dump now supports external links, displaying the target objects (datasets, groups, and named datatypes).

Tools with changed output:

Changed Library Configuration

The following configuration flag is new with this release:

--disable-sharedlib-rpath

Removed Patch Requirement

The patch that was required for Cygwin with HDF5 Release 1.8.0 has been rolled into this release and no longer needs to be applied by the user.

See the document “What’s New in HDF5 1.8.0” for a high-level overview of the new functionality in this release. The following pages assume a familiarity with that overview.

This section provides details of the API-level changes that have been made in the transition to HDF5 Release 1.8.0 from the Release 1.6.x series.

API Compatibility Macros with Associated Renamed and New Functions

Release 1.8.0 introduces API compatibility macros designed to facilitate application migration. These macros are intended to facilitate developer management of a clean, step-by-step migration from an older HDF5 Library to the new release; they can also be used to enable older applications to use the new library without requiring that the application be rewritten. See API Compatibility Macros in HDF5 for a full description.

Macros are identified in reference manual function indexes by an italic typeface.

The new macros and the new and old functions to which they may be mapped are as follows:

H5Acreate	H5Acreate1  H5Acreate2	Renamed from H5Acreate New
H5Aiterate	H5Aiterate1  H5Aiterate2	Renamed from H5Aiterate New
H5Dcreate	H5Dcreate1  H5Dcreate2	Renamed from H5Dcreate New
H5Dopen	H5Dopen1  H5Dopen2	Renamed from H5Dopen New
H5Eclear	H5Eclear1  H5Eclear2	Renamed from H5Eclear New
H5Eget_auto	H5Eget_auto1  H5Eget_auto2	Renamed from H5Eget_auto New
H5Eprint	H5Eprint1  H5Eprint2	Renamed from H5Eprint New
H5Epush	H5Epush1  H5Epush2	Renamed from H5Epush New
H5Eset_auto	H5Eset_auto1  H5Eset_auto2	Renamed from H5Eset_auto New
H5Ewalk	H5Ewalk1  H5Ewalk2	Renamed from H5Ewalk New
H5Gcreate	H5Gcreate1  H5Gcreate2	Renamed from H5Gcreate New
H5Gopen	H5Gopen1  H5Gopen2	Renamed from H5Gopen New
H5Pget_filter	H5Pget_filter1  H5Pget_filter2	Renamed from H5Pget_filter New
H5Pget_filter_by_id	H5Pget_filter_by_id1     H5Pget_filter_by_id2	Renamed from H5Pget_filter_by_id New
H5Pinsert	H5Pinsert1  H5Pinsert2	Renamed from H5Pinsert New
H5Pregister	H5Pregister1  H5Pregister2	Renamed from H5Pregister New
H5Rget_obj_type	H5Rget_obj_type1  H5Rget_obj_type2	Renamed from H5Rget_obj_type New
H5Tarray_create	H5Tarray_create1  H5Tarray_create2	Renamed from H5Tarray_create New
H5Tcommit	H5Tcommit1  H5Tcommit2	Renamed from H5Tcommit New
H5Tget_array_dims	H5Tget_array_dims1  H5Tget_array_dims2	Renamed from H5Tget_array_dims New
H5Topen	H5Topen1  H5Topen2	Renamed from H5Topen New

(H5Dcreate and H5Dopen added to the above list in November 2010, prior to Release 1.8.6.)

New Functions and Tools

C functions:

The following C functions are new for Release 1.8.0 and, unless otherwise noted, are documented in the HDF5 Reference Manual.

Recursive iteration
H5Lvisit	herr_t H5Lvisit( hid_t group_id, H5_index_t index_type, H5_iter_order_t order, H5L_iterate_t op, void *op_data ) See entry.
H5Lvisit_by_name	herr_t H5Lvisit_by_name( hid_t loc_id, const char *group_name, H5_index_t index_type, H5_iter_order_t order, H5L_iterate_t op, void *op_data, hid_t lapl_id ) See entry.
H5Ovisit	herr_t H5Ovisit( hid_t group_id, H5_index_t index_type, H5_iter_order_t order, H5O_iterate_t op, void *op_data ) See entry.
H5Ovisit_by_name	herr_t H5Ovisit_by_name( hid_t loc_id, const char *object_name, H5_index_t index_type, H5_iter_order_t order, H5O_iterate_t op, void *op_data, hid_t lapl_id ) See entry.
“Format bounds” property Release-to-release format compatibility
H5Pset_libver_bounds	herr_t H5Pset_libver_bounds( hid_t fapl_id, H5F_libver_t low, H5F_libver_t high ) See entry.
H5Pget_libver_bounds	herr_t H5Pget_libver_bounds( hid_t fapl_id, H5F_libver_t *low, H5F_libver_t *high ) See entry.
Configurable compact-or-indexed groups (compact and large groups)
H5Pset_link_phase_change	herr_t H5Pset_link_phase_change( hid_t gcpl_id, unsigned max_compact, unsigned min_dense ) See entry.
H5Pget_link_phase_change	herr_t H5Pget_link_phase_change( hid_t gcpl_id, unsigned *max_compact, unsigned *min_dense ) See entry.
H5Pset_est_link_info	herr_t H5Pset_est_link_info( hid_t gcpl_id, unsigned est_num_entries, unsigned est_name_len ) See entry.
H5Pget_est_link_info	herr_t H5Pget_est_link_info( hid_t gcpl_id, unsigned *est_num_entries, unsigned *est_name_len ) See entry.
H5Pset_nlinks	herr_t H5Pset_nlinks( hid_t lapl_id, size_t nlinks ) See entry.
H5Pget_nlinks	herr_t H5Pget_nlinks( hid_t lapl_id, size_t *nlinks ) See entry.
User-defined links
H5Lcreate_ud	herr_t H5Lcreate_ud( hid_t link_loc_id, const char *link_name, H5L_type_t link_type, const char *udata, size_t udata_size, hid_t lcpl_id, hid_t lapl_id ) See entry.
H5Lregister	herr_t H5Lregister( const H5L_class_t * link_class ) See entry.
H5Lunregister	herr_t H5Lunregister( H5L_type_t link_cls_id ) See entry.
H5Oincr_refcount	herr_t H5Oincr_refcount( hid_t object_id ) See entry.
H5Odecr_refcount	herr_t H5Odecr_refcount( hid_t object_id ) See entry.
External links
H5Lcreate_external	herr_t H5Lcreate_external( const char *file_name, const char *object_name, hid_t link_loc_id, const char *link_name, hid_t lcpl_id, hid_t lapl_id ) See entry.
H5Lunpack_elink_val	herr_t H5Lunpack_elink_val( char *ext_linkval, size_t link_size, const char **filename, const char **obj_path ) See entry.
H5Pset_elink_prefix	herr_t H5Pset_elink_prefix( hid_t lapl_id, const char *prefix ) See entry.
H5Pget_elink_prefix	herr_t H5Pget_elink_prefix( hid_t lapl_id, const char **prefix ) See entry.
Link creation order tracking and indexing
H5Pset_link_creation_order	herr_t H5Pset_link_creation_order( hid_t ocpl_id, unsigned *crt_order_flags ) See entry.
H5Pget_link_creation_order	herr_t H5Pget_link_creation_order( hid_t ocpl_id, unsigned *crt_order_flags ) See entry.
H5Gget_create_plist	hid_t H5Gget_create_plist( hid_t group_id ) See entry.
H5Gget_info_by_idx	herr_t H5Gget_info_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_type, H5_iter_order_t order, hsize_t n, H5G_info_t *group_info, hid_t lapl_id ) See entry.
H5Tget_create_plist	hid_t H5Tget_create_plist( hid_t dtype_id ) See entry.
Link API (H5L), an all-new interface (includes user-defined and external links)
H5Lcopy	herr_t H5Lcopy( hid_t src_loc_id, const char *src_name, hid_t dest_loc_id, const char *dest_name, hid_t lcpl_id hid_t lapl_id ) See entry.
H5Lcreate_external	herr_t H5Lcreate_external( const char *file_name, const char *object_name, hid_t link_loc_id, const char *link_name, hid_t lcpl_id, hid_t lapl_id ) See entry.
H5Lcreate_hard	herr_t H5Lcreate_hard( hid_t obj_loc_id, const char *obj_name, hid_t link_loc_id, const char *link_name, hid_t lcpl_id, hid_t lapl_id ) See entry.
H5Lcreate_soft	herr_t H5Lcreate_soft( const char *target_path, hid_t link_loc_id, const char *link_name, hid_t lcpl_id, hid_t lapl_id ) See entry.
H5Lcreate_ud	herr_t H5Lcreate_ud( hid_t link_loc_id, const char *link_name, H5L_type_t link_type, const char *udata, size_t udata_size, hid_t lcpl_id, hid_t lapl_id ) See entry.
H5Ldelete	herr_t H5Ldelete( hid_t loc_id, const char *name, hid_t lapl_id ) See entry.
H5Ldelete_by_idx	herr_t H5Ldelete_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_field, H5_iter_order_t order, hsize_t n, hid_t lapl_id ) See entry.
H5Lexists	htri_t H5Lexists( hid_t loc_id, const char *name, hid_t lapl_id ) See entry.
H5Lget_info	herr_t H5Lget_info( hid_t link_loc_id, const char *link_name, H5L_info_t *link_buff, hid_t lapl_id ) See entry.
H5Lget_info_by_idx	herr_t H5Lget_info_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_field, H5_iter_order_t order, hsize_t n, H5L_info_t *link_val, hid_t lapl_id ) See entry.
H5Lget_name_by_idx	ssize_t H5Lget_name_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_field, H5_iter_order_t order, hsize_t n, char *name, size_t size, hid_t lapl_id ) See entry.
H5Lget_val	herr_t H5Lget_val( hid_t link_loc_id, const char *link_name, void *linkval_buff, size_t size, hid_t lapl_id ) See entry.
H5Lget_val_by_idx	ssize_t H5Lget_val_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_field, H5_iter_order_t order, hsize_t n, char *value_buf, size_t size, hid_t lapl_id ) See entry.
H5Lis_registered	htri_t H5Lis_registered( H5L_type_t link_cls_id ) See entry.
H5Literate	herr_t H5Literate( hid_t loc_id, H5_index_t index_type, H5_iter_order_t order, hsize_t *idx, H5L_iterate_t op, void *op_data ) See entry.
H5Literate_by_name	herr_t H5Literate( hid_t loc_id, const char *group_name, H5_index_t index_type, H5_iter_order_t order, hsize_t *idx, H5L_iterate_t op, void *op_data, hid_t *lapl_id ) See entry.
H5Lmove	herr_t H5Lmove( hid_t src_loc_id, const char *src_name, hid_t dest_loc_id, const char *dest_name, hid_t lcpl, hid_t lapl ) See entry.
H5Lregister	herr_t H5Lregister( const H5L_class_t * link_class ) See entry.
H5Lunpack_elink_val	herr_t H5Lunpack_elink_val( char *ext_linkval, size_t link_size, const char **filename, const char **obj_path ) See entry.
H5Lunregister	herr_t H5Lunregister( H5L_type_t link_cls_id ) See entry.
H5Lvisit	herr_t H5Lvisit( hid_t group_id, H5_index_t index_type, H5_iter_order_t order, H5L_iterate_t op, void *op_data ) See entry.
H5Lvisit_by_name	herr_t H5Lvisit_by_name( hid_t loc_id, const char *group_name, H5_index_t index_type, H5_iter_order_t order, H5L_iterate_t op, void *op_data, hid_t lapl_id ) See entry.
Enhanced attribute handling
H5Acreate2	hid_t H5Acreate2( hid_t loc_id, const char *obj_name, const char *attr_name, hid_t type_id, hid_t space_id, hid_t acpl_id, hid_t aapl_id, hid_t lapl_id ) See entry.
H5Adelete_by_idx	herr_t H5Adelete_by_idx( hid_t loc_id, const char *obj_name, H5_index_t idx_type, H5_iter_order_t order, hsize_t n, hid_t lapl_id ) See entry.
H5Adelete_by_name	herr_t H5Adelete_by_name( hid_t loc_id, const char *obj_name, const char *attr_name, hid_t lapl_id ) See entry.
H5Aget_info	herr_t H5Aget_info( hid_t attr_id, H5A_info_t *ainfo ) See entry.
H5Aget_info_by_idx	herr_t H5Aget_info_by_idx( hid_t loc_id, const char *obj_name, H5_index_t idx_type, H5_iter_order_t order, hsize_t n, H5A_info_t *ainfo, hid_t lapl_id ) See entry.
H5Aget_info_by_name	herr_t H5Aget_info_by_name( hid_t loc_id, const char *obj_name, const char *attr_name, H5A_info_t *ainfo, hid_t lapl_id ) See entry.
H5Aget_name_by_idx	ssize_t H5Aget_name_by_idx( hid_t loc_id, const char *obj_name, H5_index_t idx_type, H5_iter_order_t order, hsize_t n, char *name, size_t size, hid_t lapl_id ) See entry.
H5Aget_storage_size	hsize_t H5Aget_storage_size( hid_t attr_id ) See entry.
H5Aiterate2	herr_t H5Aiterate2( hid_t obj_id, H5_index_t idx_type, H5_iter_order_t order, hsize_t *n, H5A_operator2_t op, void *op_data ) See entry.
H5Aiterate_by_name	herr_t H5Aiterate_by_name( hid_t loc_id, const char *obj_name, H5_index_t idx_type, H5_iter_order_t order, hsize_t *n, H5A_operator2_t op, void *op_data, hid_t lapd_id ) See entry.
H5Aopen	herr_t H5Aopen( hid_t loc_id, const char *obj_name, const char *attr_name, hid_t aapl_id, hid_t lapl_id ) See entry.
H5Aopen_by_idx	herr_t H5Aopen_by_idx( hid_t loc_id, const char *obj_name, H5_index_t idx_type, H5_iter_order_t order, hsize_t n, hid_t aapl_id, hid_t lapl_id ) See entry.
H5Arename_by_name	herr_t H5Arename_by_name( hid_t loc_id, const char *obj_name, const char *old_attr_name, const char *new_attr_name, hid_t lapl_id ) See entry.
Managing large numbers of attributes
H5Pset_attr_phase_change	herr_t H5Pset_attr_phase_change( hid_t ocpl_id, unsigned max_compact, unsigned min_dense ) See entry.
H5Pget_attr_phase_change	herr_t H5Pget_attr_phase_change( hid_t ocpl_id, unsigned *max_compact, unsigned *min_dense ) See entry.
Attribute creation order tracking and indexing
H5Pset_attr_creation_order	herr_t H5Pset_attr_creation_order( hid_t ocpl_id, unsigned crt_order_flags ) See entry.
H5Pget_attr_creation_order	herr_t H5Pget_attr_creation_order( hid_t ocpl_id, unsigned *crt_order_flags ) See entry.
H5Aget_create_plist	hid_t H5Aget_create_plist( hid_t attr_id ) See entry.
Shared object header messages (SOHM)
H5Pset_shared_mesg_index	herr_t H5Pset_shared_mesg_index( hid_t fcpl_id, unsigned index_num, unsigned mesg_type_flags, unsigned min_mesg_size ) See entry.
H5Pset_shared_mesg_nindexes	herr_t H5Pset_shared_mesg_nindexes( hid_t plist_id, unsigned nindexes ) See entry.
H5Pset_shared_mesg_phase_change	herr_t H5Pset_shared_mesg_phase_change( hid_t fcpl_id, unsigned max_list, unsigned min_btree ) See entry.
H5Pget_shared_mesg_index	herr_t H5Pget_shared_mesg_index( hid_t fcpl_id, unsigned index_num, unsigned *mesg_type_flags, unsigned *min_mesg_size ) See entry.
H5Pget_shared_mesg_nindexes	herr_t H5Pget_shared_mesg_nindexes( hid_t fcpl_id, unsigned *nindexes ) See entry.
H5Pget_shared_mesg_phase_change	herr_t H5Pget_shared_mesg_phase_change( hid_t fcpl_id, unsigned *max_list, unsigned *min_btree ) See entry.
Enhanced local heap size management   (group meta data)
H5Pset_local_heap_size_hint	herr_t H5Pset_local_heap_size_hint( hid_t gcpl_id, size_t *size_hint ) See entry.
H5Pget_local_heap_size_hint	herr_t H5Pget_local_heap_size_hint( hid_t gcpl_id, size_t size_hint ) See entry.
UNICODE support
H5Pset_char_encoding	herr_t H5Pset_char_encoding( hid_t plist_id, H5T_cset_t encoding ) See entry.
H5Pget_char_encoding	herr_t H5Pget_char_encoding( hid_t plist_id, H5T_cset_t encoding ) See entry.

Object API (H5O), all new
H5Oclose	herr_t H5Oclose( hid_t object_id ) See entry.
H5Ocopy	herr_t H5Ocopy( hid_t src_loc_id, const char *src_name, hid_t dst_loc_id, const char *dst_name, hid_t ocp_plist_id, hid_t lcpl_id ) See entry.
H5Odecr_refcount	herr_t H5Odecr_refcount( hid_t object_id ) See entry.
H5Oget_comment	ssize_t H5Oget_comment( hid_t object_id, char *comment, size_t bufsize ) See entry.
H5Oget_comment_by_name	ssize_t H5Oget_comment_by_name( hid_t loc_id, const char *name, char *comment, size_t bufsize, hid_t lapl_id ) See entry.
H5Oget_info	herr_t H5Oget_info( hid_t object_id, H5O_info_t *obj_info ) See entry.
H5Oget_info_by_idx	herr_t H5Oget_info_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_field, H5_iter_order_t order, hsize_t n, H5O_info_t *obj_info, hid_t lapl_id ) See entry.
H5Oget_info_by_name	herr_t H5Oget_info_by_name( hid_t loc_id, const char *object_name, H5O_info_t *object_info, hid_t lapl_id ) See entry.
H5Oincr_refcount	herr_t H5Oincr_refcount( hid_t object_id ) See entry.
H5Olink	herr_t H5Olink( hid_t obj_id, hid_t new_loc_id, const char *new_link_name, hid_t lcpl, hid_t lapl ) See entry.
H5Oopen	hid_t H5Oopen( hid_t loc_id, const char *name, hid_t lapl_id ) See entry.
H5Oopen_by_addr	hid_t H5Oopen_by_addr( hid_t loc_id, haddr_t addr ) See entry.
H5Oopen_by_idx	herr_t H5Oopen_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_field, H5_iter_order_t order, hsize_t n, hid_t lapl_id ) See entry.
H5Oset_comment	herr_t H5Oset_comment( hid_t object_id, const char *comment ) See entry.
H5Oset_comment_by_name	herr_t H5Oset_comment_by_name( hid_t loc_id, const char *name, const char *comment, hid_t lapl_id ) See entry.
H5Ovisit	herr_t H5Ovisit( hid_t group_id, H5_index_t index_type, H5_iter_order_t order, H5O_iterate_t op, void *op_data ) See entry.
H5Ovisit_by_name	herr_t H5Ovisit_by_name( hid_t loc_id, const char *object_name, H5_index_t index_type, H5_iter_order_t order, H5O_iterate_t op, void *op_data, hid_t lapl_id ) See entry.
Object creation or copying with “create intermediate groups” property
H5Pset_create_intermediate_group	herr_t H5Pset_create_intermediate_group( hid_t gcpl_id, unsigned crt_intermed_group ) See entry.
H5Pget_create_intermediate_group	herr_t H5Pget_create_intermediate_group( hid_t gcpl_id, unsigned *crt_intermed_group ) See entry.
Object copy properties
H5Ocopy	herr_t H5Ocopy( hid_t src_loc_id, const char *src_name, hid_t dst_loc_id, const char *dst_name, hid_t ocp_plist_id, hid_t lcpl_id ) See entry.
H5Pset_copy_object	herr_t H5Pset_copy_object( hid_t cplist_id, unsigned copy_options ) See entry.
H5Pget_copy_object	herr_t H5Pget_copy_object( hid_t cplist_id, unsigned *copy_options ) See entry.
Improved object and file information retrieval
H5Aget_info	herr_t H5Aget_info( hid_t attr_id, H5A_info_t *ainfo ) See entry.
H5Aget_info_by_name	herr_t H5Aget_info_by_name( hid_t loc_id, const char *obj_name, const char *attr_name, H5A_info_t *ainfo, hid_t lapl_id ) See entry.
H5Aget_info_by_idx	herr_t H5Aget_info_by_idx( hid_t loc_id, const char *obj_name, H5_index_t idx_type, H5_iter_order_t order, hsize_t n, H5A_info_t *ainfo, hid_t lapl_id ) See entry.
H5Fget_info	herr_t H5Fget_info( hid_t obj_id, H5F_info_t *bh_info ) See entry.
H5Gget_info	herr_t H5Gget_info( hid_t group_id, H5G_info_t group_info ) See entry.
H5Gget_info_by_name	herr_t H5Gget_info_by_name( hid_t loc_id, const char *group_name, H5G_info_t group_info, hid_t lapl_id ) See entry.
H5Gget_info_by_idx	herr_t H5Gget_info_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_type, H5_iter_order_t order, hsize_t n, H5G_info_t group_info, hid_t lapl_id ) See entry.
H5Lget_info	herr_t H5Lget_info( hid_t link_loc_id, const char *link_name, H5L_info_t *link_buff, hid_t lapl_id ) See entry.
H5Lget_info_by_idx	herr_t H5Lget_info_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_field, H5_iter_order_t order, hsize_t n, H5L_info_t *link_val, hid_t lapl_id ) See entry.
H5Oget_info	herr_t H5Oget_info( hid_t object_id, H5O_info_t *obj_info ) See entry.
H5Oget_info_by_name	herr_t H5Oget_info_by_name( hid_t loc_id, const char *object_name, H5O_info_t *object_info, hid_t lapl_id ) See entry.
H5Oget_info_by_idx	herr_t H5Oget_info_by_idx( hid_t loc_id, const char *group_name, H5_index_t index_field, H5_iter_order_t order, hsize_t n, H5O_info_t *obj_info, hid_t lapl_id ) See entry.
Name of referenced object
H5Rget_name	ssize_t H5Rget_name( hid_t loc_id, H5R_type_t ref_type, void *ref, char *name, size_t size ) See entry.
Anonymous object creation
H5Dcreate_anon	hid_t H5Dcreate_anon( hid_t loc_id, hid_t type_id, hid_t space_id, hid_t dcpl_id, hid_t dapl_id ) See entry.
H5Gcreate_anon	hid_t H5Gcreate_anon(hid_t loc_id, const char * name, hid_t gcpl_id, hid_t gapl_id) See entry.
H5Tcommit_anon	herr_t H5Tcommit_anon( hid_t loc_id, hid_t type_id, hid_t tcpl_id, hid_t tapl_id ) See entry.
H5Lcreate_hard	herr_t H5Lcreate_hard( hid_t obj_loc_id, const char *obj_name, hid_t link_loc_id, const char *link_name, hid_t lcpl, hid_t lapl ) See entry.
New-style object creation and open functions  (includes anonymous object creation)
H5Dcreate_anon	hid_t H5Dcreate_anon( hid_t loc_id, hid_t type_id, hid_t space_id, hid_t dcpl_id, hid_t dapl_id ) See entry.
H5Dcreate2	hid_t H5Dcreate2( hid_t loc_id, const char *name, hid_t type_id, hid_t space_id, hid_t lcpl_id, hid_t dcpl_id, hid_t dapl_id ) See entry.
H5Dopen2	hid_t H5Dopen2( hid_t loc_id, const char *name, hid_t dapl_id ) See entry.
H5Gcreate_anon	hid_t H5Gcreate_anon(hid_t loc_id, const char * name, hid_t gcpl_id, hid_t gapl_id) See entry.
H5Gcreate2	hid_t H5Gcreate2( hid_t loc_id, const char *name, hid_t lcpl_id, hid_t gcpl_id, hid_t gapl_id ) See entry.
H5Gopen2	hid_t H5Gopen2( hid_t loc_id, const char * name, hid_t gapl_id ) See entry.
H5Tcommit_anon	herr_t H5Tcommit_anon( hid_t loc_id, hid_t type_id, hid_t tcpl_id, hid_t tapl_id ) See entry.
H5Tcommit2	herr_t H5Tcommit2( hid_t loc_id, const char *name, hid_t type_id, hid_t lcpl_id, hid_t tcpl_id, hid_t tapl_id ) See entry.
H5Topen2	hid_t H5Topen2( hid_t loc_id, const char * name, hid_t tapl_id ) See entry.
User-defined identifiers
H5Iregister	hid_t H5Iregister(H5I_type_t type, void *object) See entry.
H5Iregister_type	H5I_type_t H5Iregister_type(size_t hash_size, unsigned reserved, H5I_free_t free_func) See entry.
H5Idestroy_type	herr_t H5Idestroy_type(H5I_type_t type) See entry.
H5Iinc_type_ref	int H5Iinc_type_ref(H5I_type_t type) See entry.
H5Idec_type_ref	int H5Idec_type_ref(H5I_type_t type) See entry.
H5Iget_type_ref	int H5Iget_type_ref(H5I_type_t type) See entry.
Other identifier API (H5I) enhancements
H5Iclear_type	herr_t H5Iclear_type(H5I_type_t type, hbool_t force) See entry.
H5Inmembers	int H5Inmembers(H5I_type_t type, hsize_t *num_members) See entry.
H5Iobject_verify	void * H5Iobject_verify(hid_t id, H5I_type_t id_type) See entry.
H5Iremove_verify	void * H5Iremove_verify(hid_t id, H5I_type_t id_type) See entry.
H5Isearch	void * H5Isearch(H5I_type_t type, H5I_search_func_t func, void *key) See entry.
H5Itype_exists	htri_t H5Itype_exists(H5I_type_t type) See entry.
Compression filters: N-bit and scale-offset
H5Pset_nbit	herr_t H5Pset_nbit( hid_t plist_id ) See entry.
H5Pset_scaleoffset	herr_t H5Pset_scaleoffset( hid_t plist_id, H5Z_SO_scale_type_t scale_type, int scale_factor ) See entry.
User-defined datatype conversion callback functions
H5Pget_type_conv_cb	herr_t H5Pget_type_conv_cb( hid_t plist, H5T_conv_except_func_t *func, void **op_data ) See entry.
H5Pset_type_conv_cb	herr_t H5Pset_type_conv_cb( hid_t plist, H5T_conv_except_func_t func, void *op_data ) See entry.
Datatype compiler conversion check
H5Tcompiler_conv	htri_t H5Tcompiler_conv( hid_t src_id, hid_t dst_id ) See entry.
Dataset array size reduction
H5Dset_extent	herr_t H5Dset_extent( hid_t dset_id, const hsize_t *size ) See entry.
Dataspace equivalence
H5Sextent_equal	herr_t H5Sextent_equal( hid_t sid1, hid_t sid2 ) See entry.
Direct I/O, bypassing system cache
H5Pset_fapl_direct	herr_t H5Pset_fapl_direct( hid_t fapl_id, size_t alignment, size_t block_size, size_t cbuf_size ) See entry.
H5Pget_fapl_direct	herr_t H5Pget_fapl_direct( hid_t fapl_id, size_t *alignment, size_t *block_size, size_t *cbuf_size ) See entry.
Parallel I/O optimization (collective chunk I/O)
H5Pset_dxpl_mpio_chunk_opt	herr_t H5Pset_dxpl_mpio_chunk_opt(hid_t dxpl_id, H5FD_mpio_chunk_opt_t opt_mode) See entry.
H5Pset_dxpl_mpio_chunk_opt_num	herr_t H5Pset_dxpl_mpio_chunk_opt_num(hid_t dxpl_id, unsigned num_chunk_per_proc) See entry.
H5Pset_dxpl_mpio_chunk_opt_ratio	herr_t H5Pset_dxpl_mpio_chunk_opt_ratio(hid_t dxpl_id, unsigned percent_num_proc_per_chunk) See entry.
H5Pset_dxpl_mpio_collective_opt	herr_t H5Pset_dxpl_mpio_collective_opt( hid_t dxpl_id, H5FD_mpio_collective_opt_t opt_mode ) See entry.
Enhanced error handling (H5E)
H5Eauto_is_v2	herr_t H5Eauto_is_v2( hid_t estack_id, unsigned *is_stack ) See entry.
H5Eclear2	herr_t H5Eclear2( hid_t estack_id ) See entry.
H5Eclose_msg	herr_t H5Eclose_msg (hid_t mesg_id) See entry.
H5Eclose_stack	herr_t H5Eclose_stack(hid_t estack_id) See entry.
H5Ecreate_msg	hid_t H5Ecreate_msg(hid_t class, H5E_type_t msg_type, const char* mesg) See entry.
H5Eget_auto2	herr_t H5Eget_auto2(hid_t estack_id, H5E_auto2_t * func, void **client_data) See entry.
H5Eget_class_name	ssize_t H5Eget_class_name(hid_t class_id, char* name, size_t size) See entry.
H5Eget_current_stack	hid_t H5Eget_current_stack(void) See entry.
H5Eget_msg	ssize_t H5Eget_msg(hid_t mesg_id, H5E_type_t* mesg_type, char* mesg, size_t size) See entry.
H5Eget_num	ssize_t H5Eget_num(hid_t estack_id) See entry.
H5Epop	herr_t H5Epop(hid_t estack_id, size_t count) See entry.
H5Eprint2	herr_t H5Eprint2(hid_t estack_id, FILE * stream) See entry.
H5Epush2	herr_t H5Epush2(hid_t estack_id, const char *file, const char *func, unsigned line, hid_t class_id, hid_t major_id, hid_t minor_id, const char *msg, ...) See entry.
H5Eregister_class	hid_t H5Eregister_class(const char* cls_name, const char* lib_name, const char* version) See entry.
H5Eset_auto2	herr_t H5Eset_auto2(hid_t estack_id, H5E_auto2_t func, void *client_data) See entry.
H5Eset_current_stack	herr_t H5Eset_current_stack(hid_t estack_id) See entry.
H5Eunregister_class	herr_t H5Eunregister_class(hid_t class_id) See entry.
H5Ewalk2	herr_t H5Ewalk2(hid_t estack_id, H5E_direction_t direction, H5E_walk2_t func, void * client_data) See entry.
Meta data cache management
H5Fget_mdc_config	herr_t H5Fget_mdc_config(hid_t file_id, H5AC_cache_config_t *config_ptr) See entry.
H5Fget_mdc_hit_rate	herr_t H5Fget_mdc_hit_rate(hid_t file_id, double *hit_rate_ptr) See entry.
H5Fget_mdc_size	herr_t H5Fget_mdc_size(hid_t file_id, size_t *max_size_ptr, size_t *min_clean_size_ptr, size_t *cur_size_ptr, int *cur_num_entries_ptr) See entry.
H5Freset_mdc_hit_rate_stats	herr_t H5Freset_mdc_hit_rate_stats(hid_t file_id) See entry.
H5Fset_mdc_config	herr_t H5Fset_mdc_config(hid_t file_id, H5AC_cache_config_t *config_ptr) See entry.
H5Pset_mdc_config	herr_t H5Pset_mdc_config(hid_t plist_id, H5AC_cache_config_t * config_ptr) See entry.
H5Pget_mdc_config	herr_t H5Pget_mdc_config(hid_t plist_id, H5AC_cache_config_t * config_ptr) See entry.
File read/write status
H5Fget_intent	herr_t H5Fget_intent( hid_t file_id, unsigned *intent ) See entry.
Arithmetic data transform on I/O
H5Pget_data_transform	herr_t H5Pget_data_transform( hid_t plist_id, char* expression, size_t size) See entry.
H5Pset_data_transform	herr_t H5Pset_data_transform( hid_t plist, const char* expression ) See entry.
Dataspace and datatype serial conversion
H5Sdecode	hid_t H5Sdecode( const void *buf ) See entry.
H5Sencode	herr_t H5Sencode( hid_t obj_id, void *buf, size_t *nalloc ) See entry.
H5Tdecode	hid_t H5Tdecode( const void *buf ) See entry.
H5Tencode	herr_t H5Tencode( hid_t obj_id, void *buf, size_t *nalloc ) See entry.
Enhanced filter management
H5Pget_filter2	herr_t H5Pget_filter2( hid_t plist_id, unsigned idx, unsigned int *flags, size_t *cd_nelmts, unsigned cd_values[], size_t namelen, char name[], unsigned *filter_config) See entry.
H5Pget_filter_by_id2	hid_t H5Pget_filter_by_id2( hid_t plist_id, H5Z_filter_t filter_id, unsigned int *flags, size_t *cd_nelmts, unsigned int cd_values[], size_t namelen, char name[], unsigned int *filter_config) See entry.
Comparison of properties
H5Pinsert2	hid_t H5Pinsert2( hid_t plid, const char *name, size_t size, void *value, H5P_prp_set_func_t set, H5P_prp_get_func_t get, H5P_prp_delete_func_t delete, H5P_prp_copy_func_t copy, H5P_prp_compare_func_t compare, H5P_prp_close_func_t close) See entry.
H5Pregister2	herr_t H5Pregister2( hid_t class, const char * name, size_t size, void * default, H5P_prp_create_func_t create, H5P_prp_set_func_t set, H5P_prp_get_func_t get, H5P_prp_delete_func_t delete, H5P_prp_copy_func_t copy, H5P_prp_compare_func_t compare, H5P_prp_close_func_t close) See entry.
Two-way conversion between datatype and text description of datatype
H5LTtext_to_dtype	hid_t H5LTtext_to_datatype( const char *text, H5LT_lang_t lang_type) See entry.
H5LTdtype_to_text	herr_t H5LTdtype_to_text( hid_t datatype, char *str, H5LT_lang_t lang_type, size_t *len) See entry.

Fortran subroutines:

New Fortran subroutines in the main library are not yet included for Release 1.8.0-beta.

See below for Fortran routines for High-Level HDF5 APIs.

C++ wrappers:

There no new C++ wrappers for Release 1.8.0-beta.

High Level C APIs:

H5LT: The following functions have been added to the HDF5 Lite (H5LT) API:

H5LTtext_to_dtype	hid_t H5LTtext_to_datatype( const char *text, H5LT_lang_t lang_type) See entry.
H5LTdtype_to_text	herr_t H5LTdtype_to_text( hid_t datatype, char *str, H5LT_lang_t lang_type, size_t *len) See entry.
H5LTset_attribute_long_long	herr_t H5LTset_attribute_long_long( hid_t loc_id, const char *obj_name, const char *attr_name, const long_long *data, size_t *size) See entry.
H5LTget_attribute_long_long	herr_t H5LTget_attribute_long_long( hid_t loc_id, const char *obj_name, const char *attr_name, long_long *data) See entry.

Two high-level C APIs are distributed for the first time with this release:
 

• H5PT, the HDF5 Packet Table interface
• H5DS, the HDF5 Dimension Scale interface

Full documentation for these interfaces can be accessed directly from the High Level APIs overview page.

The new functions included in the packet table (H5PT) high-level APIs are as follows:

H5PTcreate_fl	hid_t H5PTcreate_fl( hid_t loc_id, const char * dset_name, hid_t dtype_id, hsize_t chunk_size )
H5PTcreate_vl	hid_t H5PTcreate_vl( hid_t loc_id, const char *dset_name, hsize_t chunk_size )
H5PTopen	hid_t H5PTopen( hid_t loc_id, const char *dset_name )
H5PTclose	herr_t H5PTclose( hid_t table_id )
H5PTappend	herr_t H5PTappend( hid_t table_id, hsize_t nrecords, const void *data)
H5PTcreate_index	herr_t H5PTcreate_index( hid_t table_id)
H5PTset_index	herr_t H5PTset_index( hid_t table_id, hsize_t pt_index)
H5PTread_packets	herr_t H5PTread_packets( hid_t table_id, hsize_t start, hsize_t nrecords, void *data)
H5PTget_next	herr_t H5PTget_next( hid_t table_id, hsize_t nrecords, void *data)
H5PTget_num_packets	herr_t H5PTget_num_packets( hid_t table_id, hsize_t * nrecords)
H5PTis_valid	herr_t H5PTis_valid( hid_t table_id)
H5PTis_varlen	herr_t H5PTis_varlen( hid_t table_id)
H5PTfree_vlen_readbuff	herr_t H5PTfree_vlen_readbuff( hid_t table_id, hsize_t bufflen, void * buff)

The new functions included in the dimension scale (H5DS) high-level APIs are as follows:

H5DSset_scale	herr_t H5DSmake_scale(hid_t dsid, char *dimname)
H5DSattach_scale	herr_t H5DSattach_scale(hid_t did, hid_t dsid, unsigned int idx)
H5DSdetach_scale	herr_t H5DSdetach_scale(hid_t did, hid_t dsid, unsigned int idx)
H5DSis_attached	htri_t H5DSis_attached(hid_t did, hid_t dsid, unsigned int idx)
H5DSis_scale	htri_t H5DSis_scale(hid_t did)
H5DSiterate_scales	herr_t H5DSiterate_scales(hid_t did, unsigned dim, int *idx, H5DS_iterate_t visitor, void *visitor_data)
H5DSset_label	herr_t H5DSset_label(hid_t did, unsigned int idx, const char *label)
H5DSget_label	ssize_t H5DSget_label(hid_t did, unsigned int idx, char *label, size_t size)
H5DSget_scale_name	hssize_t H5DSget_scale_name(hid_t did, char name, size_t *size)
H5DSget_num_scales	int H5DSget_num_scales(hid_t did, unsigned int idx)

High Level Fortan90 APIs:

Fortran90 subroutines are now available for the following high-level APIs:
     H5LT: HDF5 Lite
     H5IM: HDF5 Image
     H5TB: HDF5 Table

Tools:

h5stat

Deprecated and Deleted Functions

C functions:

 

H5Pset_fapl_gass H5Pget_fapl_gass		HDF5 no longer provides GASS support.
H5Pset_fapl_srb H5Pget_fapl_srb		HDF5 no longer provides SRB support. SRB functionality is now supported through the mechanism described in SRB — The DICE Storage Resource Broker.
H5Pset_fapl_stream H5Pget_fapl_stream		The stream virtual file driver (H5FD_STREAM) has been removed from the HDF5 distribution. The functionality was last available from http://hdf5-addons.origo.ethz.ch/.
H5Tset_overflow H5Tget_overflow		These two functions are replaced by H5Pget_type_conv_cb and H5Pset_type_conv_cb.

Several functions, subroutines, and wrappers are deprecated in this HDF5 release and may eventually be removed from the HDF5 distribution and from the HDF5 Reference Manual. A Release 1.6.x compatibility mode is provided enabling these and other Release 1.6.x compatibility features, but is available only if the HDF5 Library is configured with the default settings or with the flag --with-default-api-version=v16. Release 1.8.0 also provides macros that can be mapped selectively to 1.6.x and 1.8.0 function versions according to the needs of a user application. The backward compatibility mode is enabled in the Release 1.8.0 binaries distributed by NCSA. See API Compatibility Macros in HDF5 for full details.

 
Deprecated functions are marked in the function index at the beginning of each API section in the HDF5 Reference Manual.

Virtual File Driver Removed

This virtual file driver will remain available at http://hdf5-addons.origo.ethz.ch/. Note that as of this writing, this transition is still in progress; the necessary integration tools may not be available when HDF5 Release 1.8.0 first comes out.

Functions with New or Changed Symbols or Fixed Values

C functions:

Fortran90 subroutines:

Functions with Changed Syntax

Function syntax changes in this release are handled through the mechanism described in API Compatibility Macros in HDF5.

Exceptions:

• The function H5Eget_minor is not governed by the above-mentioned macros and its return type has changed:
  H5Eget_minor
  char *H5Eget_minor (H5E_minor_t n)
  See entry.
  An application calling H5Eget_minor from an HDF5 Library of Release 1.8.0 or later will have to free the memory associated with the return value to prevent a memory leak.
  (This note added at Release 1.8.4, November 2009.)

   

• In the function H5Dextend, the size parameter signature was changed.
  H5Dextend
  herr_t *H5Dextend( hid_t dataset_id, const hsize_t size[] )
  See entry for current information; see the Release 1.6 entry for the old signature.
  The new function signature is generally considered equivalent to the old signature, but some compilers require an exact match.
  (This note added in February 2010, following Release 1.8.4.)

Renamed Functions