H5A: Attribute Interface

Attribute API Functions

The C Interfaces:

H5Acreate H5Acreate1 * H5Acreate2 H5Acreate_by_name H5Aopen H5Aopen_by_name H5Aopen_name * H5Aopen_by_idx H5Aopen_idx * H5Aexists H5Aexists_by_name		H5Arename H5Arename_by_name H5Awrite H5Aread H5Aclose H5Aiterate H5Aiterate1 * H5Aiterate2 H5Aiterate_by_name H5Adelete H5Adelete_by_name H5Adelete_by_idx		H5Aget_info H5Aget_info_by_name H5Aget_info_by_idx H5Aget_num_attrs * H5Aget_name H5Aget_create_plist H5Aget_space H5Aget_type H5Aget_storage_size H5Aget_name_by_idx
* Use of these functions is deprecated in Release 1.8.0.

Alphabetical Listing

H5Aclose H5Acreate H5Acreate1 * H5Acreate2 H5Acreate_by_name H5Adelete H5Adelete_by_name H5Adelete_by_idx H5Aexists H5Aexists_by_name H5Aget_create_plist

H5Aget_info H5Aget_info_by_idx H5Aget_info_by_name H5Aget_name H5Aget_name_by_idx H5Aget_num_attrs * H5Aget_space H5Aget_storage_size H5Aget_type H5Aiterate H5Aiterate1 *

H5Aiterate2 H5Aiterate_by_name H5Aopen H5Aopen_by_idx H5Aopen_by_name H5Aopen_idx * H5Aopen_name * H5Aread H5Arename H5Arename_by_name H5Awrite

The Fortran Interface:
In general, each Fortran subroutine performs exactly the same task as the corresponding C function.

h5aclose_f h5acreate_f h5acreate_by_name_f h5adelete_f h5adelete_by_name_f h5adelete_by_idx_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_f h5aget_name_by_idx_f h5aget_num_attrs_f * h5aget_space_f h5aget_storage_size_f h5aget_type_f		h5aopen_f h5aopen_by_idx_f h5aopen_by_name_f h5aopen_idx_f * h5aopen_name_f * h5aread_f h5arename_f h5arename_by_name_f h5awrite_f
* Use of these functions is deprecated in Release 1.8.0.

The Attribute interface, H5A, is primarily designed to easily allow small datasets to be attached to primary datasets as metadata information. Additional goals for the H5A interface include keeping storage requirement for each attribute to a minimum and easily sharing attributes among datasets.

Because attributes are intended to be small objects, large datasets intended as additional information for a primary dataset should be stored as supplemental datasets in a group with the primary dataset. Attributes can then be attached to the group containing everything to indicate a particular type of dataset with supplemental datasets is located in the group. How small is "small" is not defined by the library and is up to the user’s interpretation.

See “HDF5 Attributes” in the HDF5 User's Guide for more information.