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H5P: Property List Interface

Property List API Functions

The functions, macros, and subroutines listed here are used to manipulate property list objects in various ways, including to reset property values. With the use of property lists, HDF5 functions have been implemented and can be used in applications with many fewer parameters than would be required without property lists.

The following index to these functions, macros, and subroutines is organized into three sections:

Fortran subroutine descriptions appear within the C function descriptions on this page. In general, a Fortran subroutine does exactly the same thing the corresponding C function does; the rare exceptions are noted in the Fortran subroutine description.

Symbolic notation in the following index is interpreted as follows:
     || This function or subroutine is available only in the parallel HDF5 library.
     * This function or subroutine is deprecated in the 1.8.x series.
     italics  This is a configurable macro name rather than a function name.


The C Interfaces:

General Operations:
General Property List Operations
 
File Operations:
File Creation Properties
File Access Properties
 
Group Operations:
Group Creation Properties
Link Operations:
Link Creation Properties
Link Access Properties
 
Dataset Operations:
Dataset Creation Properties
Dataset Access Properties
Dataset Transfer Properties
Object Operations:
Object Creation Properties
Object Copy Properties
 
Attribute Operations:
Attribute Creation Properties
 
Advanced Usage:
Generic Property Operations

General Property List Operations
  H5Pcreate
H5Pget_class
H5Pcopy
H5Pclose
 

File Creation Properties
  H5Pget_version
H5Pset_userblock
H5Pget_userblock
H5Pset_sizes
H5Pget_sizes
H5Pset_sym_k
H5Pget_sym_k
H5Pset_istore_k
H5Pget_istore_k
H5Pset_shared_mesg_nindexes
H5Pget_shared_mesg_nindexes
H5Pset_shared_mesg_index
H5Pget_shared_mesg_index
H5Pset_shared_mesg_phase_change
H5Pget_shared_mesg_phase_change

File Access Properties
  H5Pset_driver
H5Pget_driver
H5Pget_driver_info
H5Pset_fclose_degree
H5Pget_fclose_degree    
H5Pset_fapl_core
H5Pget_fapl_core
H5Pset_core_write_tracking
H5Pget_core_write_tracking
H5Pset_fapl_direct
H5Pget_fapl_direct
H5Pset_fapl_family
H5Pget_fapl_family
H5Pset_family_offset
H5Pget_family_offset
H5Pset_fapl_log
H5Pset_fapl_mpio   ||
H5Pget_fapl_mpio   ||
H5Pset_fapl_mpiposix   ||
H5Pget_fapl_mpiposix   ||
H5Pset_fapl_multi
H5Pget_fapl_multi
H5Pset_multi_type
H5Pget_multi_type
H5Pset_fapl_split
H5Pset_fapl_sec2
H5Pset_fapl_stdio
H5Pset_fapl_windows
H5Pset_file_image
H5Pget_file_image
H5Pset_file_image_callbacks
H5Pget_file_image_callbacks    
H5Pset_meta_block_size
H5Pget_meta_block_size
H5Pset_sieve_buf_size
H5Pget_sieve_buf_size
H5Pset_alignment
H5Pget_alignment
H5Pset_cache
H5Pget_cache
H5Pset_elink_file_cache_size
H5Pget_elink_file_cache_size
H5Pset_mdc_config
H5Pget_mdc_config
H5Pset_gc_references
H5Pget_gc_references
H5Pset_small_data_block_size
H5Pget_small_data_block_size
H5Pset_libver_bounds
H5Pget_libver_bounds

Group Creation Properties
  H5Pset_local_heap_size_hint
H5Pget_local_heap_size_hint
H5Pset_link_creation_order    
H5Pget_link_creation_order    
H5Pset_est_link_info
H5Pget_est_link_info
H5Pset_link_phase_change
H5Pget_link_phase_change

Link Creation Properties
  H5Pset_char_encoding
H5Pget_char_encoding
H5Pset_create_intermediate_group
H5Pget_create_intermediate_group
 

Link Access Properties
  H5Pset_nlinks
H5Pget_nlinks
H5Pset_elink_cb
H5Pget_elink_cb
H5Pset_elink_prefix
H5Pget_elink_prefix
H5Pset_elink_fapl
H5Pget_elink_fapl
H5Pset_elink_acc_flags
H5Pget_elink_acc_flags

Dataset Creation Properties
  H5Pset_layout
H5Pget_layout
H5Pset_chunk
H5Pget_chunk
H5Pset_deflate
H5Pset_fill_value
H5Pget_fill_value
H5Pfill_value_defined
H5Pset_fill_time
H5Pget_fill_time
H5Pset_alloc_time
H5Pget_alloc_time
H5Pset_filter
H5Pall_filters_avail
H5Pget_nfilters
H5Pget_filter
H5Pget_filter1  *
H5Pget_filter2
H5Pget_filter_by_id
H5Pget_filter_by_id1  *
H5Pget_filter_by_id2
H5Pmodify_filter
H5Premove_filter
H5Pset_fletcher32
H5Pset_nbit
H5Pset_scaleoffset
H5Pset_shuffle
H5Pset_szip
H5Pset_external
H5Pget_external_count
H5Pget_external

Dataset Access Properties
  H5Pset_chunk_cache H5Pget_chunk_cache H5Pset_efile_prefix
H5Pget_efile_prefix

Dataset Transfer Properties
  H5Pset_buffer
H5Pget_buffer
H5Pset_preserve  *
H5Pget_preserve  *
H5Pset_edc_check
H5Pget_edc_check
H5Pset_filter_callback
H5Pset_data_transform
H5Pget_data_transform    
H5Pset_type_conv_cb
H5Pget_type_conv_cb
H5Pset_hyper_vector_size
H5Pget_hyper_vector_size
H5Pset_btree_ratios
H5Pget_btree_ratios
H5Pset_vlen_mem_manager
H5Pget_vlen_mem_manager    
H5Pset_dxpl_mpio   ||
H5Pset_dxpl_mpio_chunk_opt   ||
H5Pset_dxpl_mpio_chunk_opt_num   ||
H5Pset_dxpl_mpio_chunk_opt_ratio   ||
H5Pset_dxpl_mpio_collective_opt   ||
H5Pget_dxpl_mpio   ||
H5Pget_mpio_actual_chunk_opt_mode   ||
H5Pget_mpio_actual_io_mode   ||
H5Pget_mpio_no_collective_cause   ||

Object Creation Properties
  H5Pset_create_intermediate_group
H5Pget_create_intermediate_group    
H5Pset_obj_track_times
H5Pget_obj_track_times
H5Pset_attr_phase_change    
H5Pget_attr_phase_change
H5Pset_attr_creation_order
H5Pget_attr_creation_order

Object Copy Properties
  H5Pset_copy_object
H5Pget_copy_object    
H5Padd_merge_committed_dtype_path
H5Pfree_merge_committed_dtype_paths    
H5Pset_mcdt_search_cb
H5Pget_mcdt_search_cb

Attribute Creation Properties
  H5Pset_char_encoding H5Pget_char_encoding  

Generic Property Operations (Advanced)
  H5Pcreate_class
H5Pregister
H5Pregister1  *
H5Pregister2
H5Pinsert
H5Pinsert1  *
H5Pinsert2
H5Pset
H5Pexist
H5Pget_size
H5Pget_nprops
H5Pget_class_name
H5Pget_class_parent
H5Pisa_class
H5Pget
H5Pequal
H5Piterate
H5Pcopy_prop
H5Premove
H5Punregister
H5Pclose_class


 

  

Alphabetic Listing
  H5Padd_merge_committed_dtype_path
H5Pall_filters_avail
H5Pclose
H5Pclose_class
H5Pcopy
H5Pcopy_prop
H5Pcreate
H5Pcreate_class
H5Pequal
H5Pexist
H5Pfill_value_defined
H5Pfree_merge_committed_dtype_paths
H5Pget
H5Pget_alignment
H5Pget_alloc_time
H5Pget_attr_creation_order
H5Pget_attr_phase_change
H5Pget_btree_ratios
H5Pget_buffer
H5Pget_cache
H5Pget_char_encoding
H5Pget_chunk
H5Pget_chunk_cache
H5Pget_class
H5Pget_class_name
H5Pget_class_parent
H5Pget_copy_object
H5Pget_core_write_tracking
H5Pget_create_intermediate_group
H5Pget_data_transform
H5Pget_driver
H5Pget_driver_info
H5Pget_dxpl_mpio   ||
H5Pget_edc_check
H5Pget_efile_prefix
H5Pget_elink_acc_flags
H5Pget_elink_cb
H5Pget_elink_fapl
H5Pget_elink_file_cache_size
H5Pget_elink_prefix
H5Pget_est_link_info
H5Pget_external
H5Pget_external_count
H5Pget_family_offset
H5Pget_fapl_core
H5Pget_fapl_direct
H5Pget_fapl_family
H5Pget_fapl_mpio   ||
H5Pget_fapl_mpiposix   ||
H5Pget_fapl_multi
H5Pget_fclose_degree
H5Pget_file_image
H5Pget_file_image_callbacks
H5Pget_fill_time
H5Pget_fill_value
H5Pget_filter
H5Pget_filter1  *
H5Pget_filter2
H5Pget_filter_by_id
H5Pget_filter_by_id1  *
H5Pget_filter_by_id2
    H5Pget_gc_references
H5Pget_hyper_vector_size
H5Pget_istore_k
H5Pget_layout
H5Pget_libver_bounds
H5Pget_link_creation_order
H5Pget_link_phase_change
H5Pget_local_heap_size_hint
H5Pget_mcdt_search_cb
H5Pget_mdc_config
H5Pget_meta_block_size
H5Pget_mpio_actual_chunk_opt_mode   ||
H5Pget_mpio_actual_io_mode   ||
H5Pget_mpio_no_collective_cause   ||
H5Pget_multi_type
H5Pget_nfilters
H5Pget_nlinks
H5Pget_nprops
H5Pget_preserve  *
H5Pget_obj_track_times
H5Pget_shared_mesg_index
H5Pget_shared_mesg_nindexes
H5Pget_shared_mesg_phase_change
H5Pget_sieve_buf_size
H5Pget_size
H5Pget_sizes
H5Pget_small_data_block_size
H5Pget_sym_k
H5Pget_type_conv_cb
H5Pget_userblock
H5Pget_version
H5Pget_vlen_mem_manager
H5Pinsert
H5Pinsert1  *
H5Pinsert2
H5Pisa_class
H5Piterate
H5Pmodify_filter
H5Pregister
H5Pregister1  *
H5Pregister2
H5Premove
H5Premove_filter
H5Pset
H5Pset_alignment
H5Pset_alloc_time
H5Pset_attr_creation_order
H5Pset_attr_phase_change
H5Pset_btree_ratios
H5Pset_buffer
H5Pset_cache
H5Pset_char_encoding
H5Pset_chunk
H5Pset_chunk_cache
H5Pset_copy_object
H5Pset_core_write_tracking
H5Pset_create_intermediate_group
H5Pset_data_transform
H5Pset_deflate
H5Pset_driver
H5Pset_dxpl_mpio   ||
H5Pset_dxpl_mpio_chunk_opt   ||
H5Pset_dxpl_mpio_chunk_opt_num   ||
    H5Pset_dxpl_mpio_chunk_opt_ratio   ||
H5Pset_dxpl_mpio_collective_opt   ||
H5Pset_edc_check
H5Pset_efile_prefix
H5Pset_elink_acc_flags
H5Pset_elink_cb
H5Pset_elink_fapl
H5Pset_elink_file_cache_size
H5Pset_elink_prefix
H5Pset_est_link_info
H5Pset_external
H5Pset_family_offset
H5Pset_fapl_core
H5Pset_fapl_family
H5Pset_fapl_direct
H5Pset_fapl_log
H5Pset_fapl_mpio   ||
H5Pset_fapl_mpiposix   ||
H5Pset_fapl_multi
H5Pset_fapl_sec2
H5Pset_fapl_split
H5Pset_fapl_stdio
H5Pset_fapl_windows
H5Pset_fclose_degree
H5Pset_file_image
H5Pset_file_image_callbacks
H5Pset_fill_time
H5Pset_fill_value
H5Pset_filter
H5Pset_filter_callback
H5Pset_fletcher32
H5Pset_gc_references
H5Pset_hyper_vector_size
H5Pset_istore_k
H5Pset_layout
H5Pset_libver_bounds
H5Pset_link_creation_order
H5Pset_link_phase_change
H5Pset_local_heap_size_hint
H5Pset_mcdt_search_cb
H5Pset_mdc_config
H5Pset_meta_block_size
H5Pset_multi_type
H5Pset_nbit
H5Pset_nlinks
H5Pset_preserve  *
H5Pset_obj_track_times
H5Pset_scaleoffset
H5Pset_shared_mesg_index
H5Pset_shared_mesg_nindexes
H5Pset_shared_mesg_phase_change
H5Pset_shuffle
H5Pset_sieve_buf_size
H5Pset_sizes
H5Pset_small_data_block_size
H5Pset_sym_k
H5Pset_szip
H5Pset_type_conv_cb
H5Pset_userblock
H5Pset_vlen_mem_manager
H5Punregister


 


The Fortran Interface:

General Operations:
General Property List Operations
 
File Operations:
File Creation Properties
File Access Properties
 
Group Operations:
Group Creation Properties
Link Operations:
Link Creation Properties
Link Access Properties
 
Dataset Operations:
Dataset Creation Properties
Dataset Access Properties
Dataset Transfer Properties
Object Operations:
Object Creation Properties
Object Copy Properties
 
Attribute Operations:
Attribute Creation Properties
 
Advanced Usage:
Generic Property Operations

General Property List Operations
  h5pcreate_f
h5pget_class_f
h5pcopy_f
h5pclose_f
 

File Creation Properties
  h5pget_version_f
h5pset_userblock_f
h5pget_userblock_f
h5pset_sizes_f
h5pget_sizes_f
h5pset_sym_k_f
h5pget_sym_k_f
h5pset_istore_k_f
h5pget_istore_k_f
h5pset_shared_mesg_nindexes_f
h5pset_shared_mesg_index_f

File Access Properties
  h5pset_fclose_degree_f
h5pget_fclose_degree_f
h5pset_fapl_core_f
h5pget_fapl_core_f
h5pset_fapl_direct_f
h5pget_fapl_direct_f
h5pset_fapl_family_f
h5pget_fapl_family_f
h5pset_family_offset_f
h5pset_fapl_mpio_f   ||
h5pget_fapl_mpio_f   ||
h5pset_fapl_mpiposix_f   ||
h5pget_fapl_mpiposix_f   ||
h5pset_fapl_multi_f
h5pget_fapl_multi_f
h5pset_fapl_split_f
h5pset_fapl_sec2_f
h5pset_fapl_stdio_f
h5pset_file_image_f
h5pget_file_image_f
h5pget_driver_f
h5pset_meta_block_size_f
h5pget_meta_block_size_f
h5pset_sieve_buf_size_f
h5pget_sieve_buf_size_f
h5pset_alignment_f
h5pget_alignment_f
h5pset_cache_f
h5pget_cache_f
h5pset_gc_references_f
h5pget_gc_references_f
h5pset_small_data_block_size_f
h5pget_small_data_block_size_f
h5pset_libver_bounds_f

Group Creation Properties
  h5pset_local_heap_size_hint_f
h5pget_local_heap_size_hint_f
h5pset_link_creation_order_f
h5pget_link_creation_order_f
h5pset_est_link_info_f
h5pget_est_link_info_f
h5pset_link_phase_change_f
h5pget_link_phase_change_f

Link Creation Properties
  h5pset_char_encoding_f h5pget_char_encoding_f  

Link Access Properties
  h5pset_nlinks_f h5pget_nlinks_f  

Dataset Creation Properties
  h5pset_layout_f
h5pget_layout_f
h5pset_chunk_f
h5pget_chunk_f
h5pset_deflate_f
h5pset_fill_value_f
h5pget_fill_value_f
h5pset_fill_time_f
h5pget_fill_time_f
h5pset_alloc_time_f
h5pget_alloc_time_f
h5pset_filter_f
h5pget_nfilters_f
h5pget_filter_f
h5pget_filter_by_id_f
h5pmodify_filter_f
h5premove_filter_f
h5pset_fletcher32_f
h5pset_nbit_f
h5pset_scaleoffset_f
h5pset_shuffle_f
h5pset_szip_f
h5pset_external_f
h5pget_external_count_f
h5pget_external_f

Dataset Access Properties
  h5pset_chunk_cache_f h5pget_chunk_cache_f  

Dataset Transfer Properties
  h5pset_buffer_f
h5pget_buffer_f
h5pset_preserve_f  *
h5pget_preserve_f  *
h5pset_edc_check_f
h5pget_edc_check_f
h5pset_data_transform_f
h5pget_data_transform_f
h5pset_hyper_vector_size_f
h5pget_hyper_vector_size_f
h5pset_btree_ratios_f
h5pget_btree_ratios_f
h5pset_dxpl_mpio_f   ||
h5pget_dxpl_mpio_f   ||
h5pget_mpio_actual_io_mode_f   ||

Object Creation Properties
  h5pset_create_inter_group_f
h5pget_create_inter_group_f
h5pset_attr_phase_change_f
h5pget_attr_phase_change_f
h5pset_attr_creation_order_f
h5pget_attr_creation_order_f
h5pset_obj_track_times_f
h5pget_obj_track_times_f

Object Copy Properties
  h5pset_copy_object_f h5pget_copy_object_f  

Attribute Creation Properties
  h5pset_char_encoding_f h5pget_char_encoding_f  

Generic Property Operations (Advanced)
  h5pcreate_class_f
h5pregister_f
h5pinsert_f
h5pset_f
h5pget_f
h5pexist_f
h5pget_size_f
h5pget_nprops_f
h5pget_class_name_f
h5pget_class_parent_f
h5pisa_class_f
h5pequal_f
h5pcopy_prop_f
h5premove_f
h5punregister_f
h5pclose_class_f



Last modified: 21 March 2012
Name: H5Padd_merge_committed_dtype_path
Signature:
herr_t H5Padd_merge_committed_dtype_path( hid_t ocpypl_id, char *path )

Purpose:
Adds a path to the list of paths that will be searched in the destination file for a matching committed datatype.

Motivation:
H5Padd_merge_committed_dtype_path provides a means to override the default behavior of H5Ocopy when H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG is set in an object copy property list.

H5Padd_merge_committed_dtype_path is the mechanism for suggesting search paths where H5Ocopy will look for a matching committed datatype. This can be substantially faster than the default approach of searching the entire destination file for a match.

Description:
H5Padd_merge_committed_dtype_path adds a path, path, which points to a committed datatype, to the current list of suggested paths stored in the object copy property list ocpypl_id. The search as described in the next paragraph is effective only if the H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG is enabled in the object copy property list via H5Pset_copy_object.

When copying a committed datatype, a dataset with a committed datatype, or an object with an attribute of a committed datatype, the default behavior of H5Ocopy is to search for a matching committed datatype:

  1. First search the list of suggested paths in the object copy property list.
  2. Then, if no match has been found, search all the committed datatypes in the destination file.

The default Step 2 in this search process can changed by setting a callback function (see H5Pset_mcdt_search_cb).

Two datatypes are determined equal if their descriptions are identical, in a manner similar to H5Tequal. If either committed datatype has one or more attributes, then all attributes must be present in both committed datatypes and they must be identical. Two attributes are considered identical if their datatype description, dataspace, and raw data values are the same. However, if an attribute uses a committed datatype, that committed datatype’s attributes will not be compared.

If a match is found, H5Ocopy will perform the following in the destination file:

If no match is found, H5Ocopy will perform the following in the destination file:

Parameters:
hid_t ocpypl_id      IN: Object copy property list identifier.
char *path   IN: The path to be added.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Failure Modes:
H5Padd_merge_committed_dtype_path will fail if the object copy property list is invalid.

It will also fail if there is insufficient memory when duplicating path.

Example Usage:
This example adds two paths to the object copy property list. H5Ocopy will search the two suggested paths for a match before searching all the committed datatypes in the destination file.

int main(void) {
    hid_t ocpypl_id = H5Pcreate(H5P_OBJECT_COPY);

    /* Enable the merging committed datatype feature */
    H5Pset_copy_object(ocpypl_id, H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG);

    /* Add a path to a committed datatype */
    H5Padd_merge_committed_dtype_path(ocpypl_id, "/group/committed_dtypeA");

    /* Add a path to a dataset with committed datatype */
    H5Padd_merge_committed_dtype_path(ocpypl_id, "/group2/committed_dset");
    
    /* Does the copy */
    H5Ocopy(...ocpypl_id...);
    ...
    ...
}
        

See Also:
H5Ocopy
H5Pset_copy_object
  H5Pset_mcdt_search_cb
H5Pfree_merge_committed_dtype_paths

Copying Committed Datatypes
    with H5Ocopy
 
A comprehensive discussion of copying committed datatypes (PDF) in Advanced Topics in HDF5

History:
Release     Change
1.8.9 C function introduced in this release.

Last modified: 10 June 2010
Name: H5Pall_filters_avail
Signature:
htri_t H5Pall_filters_avail( hid_t plist_id )

Purpose:
Verifies that all required filters are available.

Description:
H5Pall_filters_avail verifies that all of the filters set in the dataset or group creation property list plist_id are currently available.

Parameters:
hid_t plist_id     IN: Dataset or group creation property list identifier.

Returns:
Returns TRUE if all filters are available and FALSE if one or more is not currently available.
Returns FAIL, a negative value, on error.

Fortran90 Interface:
None.

History:

Name: H5Pclose
Signature:
herr_t H5Pclose(hid_t plist )
Purpose:
Terminates access to a property list.
Description:
H5Pclose terminates access to a property list. All property lists should be closed when the application is finished accessing them. This frees resources used by the property list.
Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pclose_f
SUBROUTINE h5pclose_f(prp_id, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier 
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pclose_f
	

Name: H5Pclose_class
Signature:
herr_t H5Pclose_class( hid_t class )
Purpose:
Closes an existing property list class.
Description:
Removes a property list class from the library.

Existing property lists of this class will continue to exist, but new ones are not able to be created.

Parameters:
Returns:
Success: a non-negative value
Failure: a negative value
Fortran90 Interface: h5pclose_class_f
SUBROUTINE h5pclose_class_f(class, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: class ! Property list class identifier 
                                      ! to close
  INTEGER, INTENT(OUT) :: hdferr      ! Error code
                                      ! 0 on success and -1 on failure
END SUBROUTINE h5pclose_class_f
	

Name: H5Pcopy
Signature:
hid_t H5Pcopy(hid_t plist )
Purpose:
Copies an existing property list to create a new property list.
Description:
H5Pcopy copies an existing property list to create a new property list. The new property list has the same properties and values as the original property list.
Parameters:
Returns:
Returns a property list identifier if successful; otherwise returns a negative value.
Fortran90 Interface: h5pcopy_f
SUBROUTINE h5pcopy_f(prp_id, new_prp_id, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id       ! Property list identifier 
  INTEGER(HID_T), INTENT(OUT) :: new_prp_id  ! Identifier  of property list
                                             ! copy  
  INTEGER, INTENT(OUT) :: hdferr             ! Error code
                                             ! 0 on success and -1 on failure
END SUBROUTINE h5pcopy_f
	

Name: H5Pcopy_prop
Signature:
herr_t H5Pcopy_prop( hid_t dst_id, hid_t src_id, const char *name )
Purpose:
Copies a property from one list or class to another.
Description:
H5Pcopy_prop copies a property from one property list or class to another.

If a property is copied from one class to another, all the property information will be first deleted from the destination class and then the property information will be copied from the source class into the destination class.

If a property is copied from one list to another, the property will be first deleted from the destination list (generating a call to the close callback for the property, if one exists) and then the property is copied from the source list to the destination list (generating a call to the copy callback for the property, if one exists).

If the property does not exist in the class or list, this call is equivalent to calling H5Pregister or H5Pinsert (for a class or list, as appropriate) and the create callback will be called in the case of the property being copied into a list (if such a callback exists for the property).

Parameters:
Returns:
Success: a non-negative value
Failure: a negative value
Fortran90 Interface: h5pcopy_prop_f
SUBROUTINE h5pcopy_prop_f(dst_id, src_id, name, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: dst_id  ! Destination property list 
                                        ! identifier 
  INTEGER(HID_T), INTENT(IN) :: src_id  ! Source property list identifier 
  CHARACTER(LEN=*), INTENT(IN) :: name  ! Property name
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pcopy_prop_f
	

Last modified: 8 April 2015
Name: H5Pcreate

Signature:
hid_t H5Pcreate( hid_t cls_id )

Purpose:
Creates a new property list as an instance of a property list class.

Description:
H5Pcreate creates a new property list as an instance of some property list class. The new property list is initialized with default values for the specified class. The classes are as follows; see the function index at the top of this page for a list of functions related to each class:

H5Pcreate Class Identifier H5Pget_class_name Class Name Comments
H5P_ATTRIBUTE_CREATE attribute create Properties for attribute creation
H5P_DATASET_ACCESS dataset access Properties for dataset access
H5P_DATASET_CREATE dataset create Properties for dataset creation
H5P_DATASET_XFER data transfer Properties for raw data transfer
H5P_DATATYPE_ACCESS datatype access Properties for datatype access
H5P_DATATYPE_CREATE datatype create Properties for datatype creation
H5P_FILE_ACCESS file access Properties for file access
H5P_FILE_CREATE file create Properties for file creation
H5P_FILE_MOUNT file mount Properties for file mounting
H5P_GROUP_ACCESS group access Properties for group access
H5P_GROUP_CREATE group create Properties for group creation
H5P_LINK_ACCESS link access Properties governing link traversal when accessing objects
H5P_LINK_CREATE link create Properties governing link creation
H5P_OBJECT_COPY object copy Properties governing the object copying process
H5P_OBJECT_CREATE object create Properties for object creation
H5P_STRING_CREATE string create Properties for character encoding when encoding strings or object names

This property list must eventually be closed with H5Pclose; otherwise, errors are likely to occur.


Parameters:
hid_t cls_id     IN: The class of the property list to create. Valid values are listed in the “Description” above.

Returns:
Returns a property list identifier (plist) if successful; otherwise Fail (-1).

Fortran90 Interface: h5pcreate_f
SUBROUTINE h5pcreate_f(classtype, prp_id, hdferr) 
  IMPLICIT NONE
  INTEGER, INTENT(IN) :: classtype       ! The type of the property list 
                                         ! to be created 
                                         ! Possible values are: 
                                         !    H5P_ATTRIBUTE_CREATE_F
                                         !    H5P_DATASET_ACCESS_F
                                         !    H5P_DATASET_CREATE_F
                                         !    H5P_DATASET_XFER_F
                                         !    H5P_DATATYPE_ACCESS_F
                                         !    H5P_DATATYPE_CREATE_F
                                         !    H5P_FILE_ACCESS_F
                                         !    H5P_FILE_CREATE_F
                                         !    H5P_FILE_MOUNT_F
                                         !    H5P_GROUP_ACCESS_F
                                         !    H5P_GROUP_CREATE_F
                                         !    H5P_LINK_ACCESS_F
                                         !    H5P_LINK_CREATE_F
                                         !    H5P_OBJECT_COPY_F
                                         !    H5P_OBJECT_CREATE_F
                                         !    H5P_STRING_CREATE_F
  INTEGER(HID_T), INTENT(OUT) :: prp_id  ! Property list identifier 
  INTEGER, INTENT(OUT) :: hdferr         ! Error code
                                         ! 0 on success and -1 on failure
END SUBROUTINE h5pcreate_f
    
See Also:
H5Pget_class_name
“Using Identifiers”

History:
Release     Change
1.8.0 The following property list classes were added at this release:
        H5P_DATASET_ACCESS 
        H5P_GROUP_CREATE 
        H5P_GROUP_ACCESS 
        H5P_DATATYPE_CREATE 
        H5P_DATATYPE_ACCESS 
        H5P_ATTRIBUTE_CREATE                   
1.8.15 For each class, the class name returned by H5Pget_class_name was added.
The list of possible Fortran values was updated.

Last modified: 26 March 2014
Name: H5Pcreate_class

Signature:
hid_t H5Pcreate_class( hid_t parent_class, const char *name, H5P_cls_create_func_t create, void *create_data, H5P_cls_copy_func_t copy, void *copy_data, H5P_cls_close_func_t close, void *close_data )

Purpose:
Creates a new property list class.

Description:
H5Pcreate_class registers a new property list class with the library. The new property list class can inherit from an existing property list class, parent_class, or may be derived from the default “empty” class, NULL. New classes with inherited properties from existing classes may not remove those existing properties, only add or remove their own class properties. Property list classes defined and supported in the HDF5 Library distribution are listed and briefly described in H5Pcreate.

The create routine is called when a new property list of this class is being created. The H5P_cls_create_func_t callback function is defined as follows: The parameters to this callback function are defined as follows: The create routine is called after any registered create function is called for each property value. If the create routine returns a negative value, the new list is not returned to the user and the property list creation routine returns an error value.

The copy routine is called when an existing property list of this class is copied. The H5P_cls_copy_func_t callback function is defined as follows: The parameters to this callback function are defined as follows: The copy routine is called after any registered copy function is called for each property value. If the copy routine returns a negative value, the new list is not returned to the user and the property list copy routine returns an error value.

The close routine is called when a property list of this class is being closed. The H5P_cls_close_func_t callback function is defined as follows: The parameters to this callback function are defined as follows: The close routine is called before any registered close function is called for each property value. If the close routine returns a negative value, the property list close routine returns an error value but the property list is still closed.

Parameters:

Returns:
On success, returns a valid property list class identifier; otherwise returns a negative value.

H5Pclose_class can be used to release the property list class identifier returned by this function so that resources leaks will not develop.

Fortran90 Interface: h5pcreate_class_f
SUBROUTINE h5pcreate_class_f(parent, name, class, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: parent  ! Parent property list class 
                                        ! identifier
                                        ! Possible values include:
                                        !    H5P_NO_CLASS_F
                                        !    H5P_FILE_CREATE_F
                                        !    H5P_FILE_ACCESS_F
                                        !    H5P_DATASET_CREATE_F
                                        !    H5P_DATASET_XFER_F
                                        !    H5P_FILE_MOUNT_F
  CHARACTER(LEN=*), INTENT(IN) :: name  ! Name of property to create 
  INTEGER(HID_T), INTENT(OUT) :: class  ! Property list class identifier
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pcreate_class_f
    

Fortran2003 Interface: h5pcreate_class_f
Signature:

  SUBROUTINE h5pcreate_class_f(parent, name, class, hdferr, create, &
            create_data, copy, copy_data, close, close_data)
    INTEGER(HID_T)  , INTENT(IN)  :: parent
    CHARACTER(LEN=*), INTENT(IN)  :: name
    INTEGER(HID_T)  , INTENT(OUT) :: class
    INTEGER         , INTENT(OUT) :: hdferr
    TYPE(C_PTR)     , OPTIONAL    :: create_data, copy_data, close_data
    TYPE(C_FUNPTR)  , OPTIONAL    :: create, copy, close

Inputs:

  parent  - Parent property list class identifier
            Possible values include:
              H5P_ROOT_F
              H5P_FILE_CREATE_F
              H5P_FILE_ACCESS_F
              H5P_DATASET_CREATE_F
              H5P_DATASET_XFER_F
              H5P_FILE_MOUNT_F
  name    - Name of property to create

Outputs:

  class   - Property list class identifier
  hdferr  - Returns 0 if successful and -1 if fails

Optional parameters:

  H5P_cls_create_func_t (create) - Callback routine called when a 
                                   property list is created
  create_data                    - User pointer to any class creation 
                                   information needed
  H5P_cls_copy_func_t   (copy)   - Callback routine called when a property 
                                   list is copied
  copy_data                      - User pointer to any class copy 
                                   information needed
  H5P_cls_close_func_t  (close)  - Callback routine called when a property 
                                   list is being closed
  close_data                     - User pointer to any class close 
                                   information needed

History:
Release     Change
1.8.8 Fortran updated to Fortran2003.

Name: H5Pequal
Signature:
htri_t H5Pequal( hid_t id1, hid_t id2 )
Purpose:
Compares two property lists or classes for equality.
Description:
H5Pequal compares two property lists or classes to determine whether they are equal to one another.

Either both id1 and id2 must be property lists or both must be classes; comparing a list to a class is an error.

Parameters:
Returns:
Success: TRUE (positive) if equal; FALSE (zero) if unequal
Failure: a negative value
Fortran90 Interface: h5pequal_f
SUBROUTINE h5pequal_f(plist1_id, plist2_id, flag, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist1_id ! Property list identifier
  INTEGER(HID_T), INTENT(IN) :: plist2_id ! Property list identifier
  LOGICAL, INTENET(OUT)      :: flag      ! Flag
                                          !    .TRUE. if lists are equal 
                                          !    .FALSE. otherwise 
  INTEGER, INTENT(OUT)       :: hdferr    ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pequal_f
	

Name: H5Pexist
Signature:
htri_t H5Pexist( hid_t id, const char *name )
Purpose:
Queries whether a property name exists in a property list or class.
Description:
H5Pexist determines whether a property exists within a property list or class.
Parameters:
Returns:
Success: a positive value if the property exists in the property object; zero if the property does not exist
Failure: a negative value
Fortran90 Interface: h5pexist_f
SUBROUTINE h5pexist_f(prp_id, name, flag, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier 
  CHARACTER(LEN=*), INTENT(IN) :: name  ! Name of property to modify
  LOGICAL, INTENT(OUT) :: flag          ! Logical flag
                                        !    .TRUE. if exists 
                                        !    .FALSE. otherwise
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pexist_f
	

Name: H5Pfill_value_defined
Signature:
herr_t H5Pfill_value_defined(hid_t plist_id, H5D_fill_value_t *status )
Purpose:
Determines whether fill value is defined.
Description:
H5Pfill_value_defined determines whether a fill value is defined in the dataset creation property list plist_id.

Valid values returned in status are as follows:
     H5D_FILL_VALUE_UNDEFINED Fill value is undefined.
H5D_FILL_VALUE_DEFAULT Fill value is the library default.
H5D_FILL_VALUE_USER_DEFINED   Fill value is defined by the application.

Note:
H5Pfill_value_defined is designed for use in concert with the dataset fill value properties functions H5Pget_fill_value and H5Pget_fill_time.

See H5Dcreate for further cross-references.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface:
None.
History:

Last modified: 21 March 2012
Name: H5Pfree_merge_committed_dtype_paths
Signature:
herr_t H5Pfree_merge_committed_dtype_paths( hid_t ocpypl_id )

Purpose:
Clears the list of paths stored in the object copy property list ocpypl_id. These are the suggested paths previously set with H5Padd_merge_committed_dtype_path.

Description:
H5Pfree_merge_committed_dtype_paths clears the suggested paths stored in the object copy property list ocpypl_id.

Parameters:
hid_t ocpypl_id      IN: Object copy property list identifier.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Failure Modes:
H5Pfree_merge_committed_dtype_paths will fail if the object copy property list is invalid.

Example Usage:
This example adds a suggested path to the object copy property list, does the copy, clears the list, and then adds a new suggested path to the list for another copy.
int main(void) {
    hid_t ocpypl_id = H5Pcreate(H5P_OBJECT_COPY);

    /* Enable the merging committed datatype feature. */
    H5Pset_copy_object(ocpypl_id, H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG);

    /* Add a path to search for a matching committed datatype. */
    H5Padd_merge_committed_dtype_path(ocpypl_id, "/group/committed_dtypeA");

    /* Do the copy. */
    H5Ocopy(...ocpypl_id...);
    ...
    ...
    /* Free the previous suggested path. */
    H5Pfree_merge_committed_dtype_paths(ocpypl_id);

    /* Add a path to search for a matching committed datatype. */
    H5Padd_merge_committed_dtype_path(ocpypl_id, "/group2/committed_dtypeB");

    /* Do the copy. */
    H5Ocopy(...ocpypl_id...);
    ...
    ...
}

See Also:
H5Ocopy
H5Pset_copy_object
  H5Pset_mcdt_search_cb
H5Padd_merge_committed_dtype_path

Copying Committed Datatypes
    with H5Ocopy
 
A comprehensive discussion of copying committed datatypes (PDF) in Advanced Topics in HDF5

History:
Release     Change
1.8.9 C function introduced in this release.

Last modified: 29 September 2011
Name: H5Pget
Signature:
herr_t H5Pget( hid_t plid, const char *name, void *value )

Purpose:
Queries the value of a property.

Description:
H5Pget retrieves a copy of the value for a property in a property list. If there is a get callback routine registered for this property, the copy of the value of the property will first be passed to that routine and any changes to the copy of the value will be used when returning the property value from this routine.

This routine may be called for zero-sized properties with the value set to NULL. The get routine will be called with a NULL value if the callback exists.

The property name must exist or this routine will fail.

If the get callback routine returns an error, value will not be modified.

Parameters:
hid_t plid IN: Identifier of the property list to query
const char *name     IN: Name of property to query
void *value OUT: Pointer to a location to which to copy the value of of the property

Returns:
Success: a non-negative value
Failure: a negative value

Fortran90 Interface: h5pget_f
Signature:

  SUBROUTINE h5pget_f(plid, name, value, hdferr)
    INTEGER(HID_T)  , INTENT(IN)  :: plid
    CHARACTER(LEN=*), INTENT(IN)  :: name
    TYPE            , INTENT(OUT) :: value
    INTEGER         , INTENT(OUT) :: hdferr

Inputs:

  prp_id  - Property list identifier to modify
  name    - Name of property to get
  value   - Property value, supported types are:
             INTEGER
             REAL
             DOUBLE PRECISION
             CHARACTER(LEN=*)

Outputs:

  hdferr  - Returns 0 if successful and -1 if fails

Fortran2003 Interface: h5pget_f
Signature:

  SUBROUTINE h5pget_f(plid, name, value, hdferr)
    INTEGER(HID_T)  , INTENT(IN)  :: plid
    CHARACTER(LEN=*), INTENT(IN)  :: name
    TYPE(C_PTR)     , INTENT(OUT) :: value
    INTEGER         , INTENT(OUT) :: hdferr

Inputs:

  prp_id  - Property list identifier to modify
  name    - Name of property to get
  value   - Pointer to a location to which to copy the value of 
            the property

Outputs:

  hdferr  - Returns 0 if successful and -1 if fails

History:
Release     Change
1.8.8 Fortran updated to Fortran2003.

Name: H5Pget_alignment
Signature:
herr_t H5Pget_alignment(hid_t plist, hsize_t *threshold, hsize_t *alignment )
Purpose:
Retrieves the current settings for alignment properties from a file access property list.
Description:
H5Pget_alignment retrieves the current settings for alignment properties from a file access property list. The threshold and/or alignment pointers may be null pointers (NULL).
Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_alignment_f
SUBROUTINE h5pget_alignment_f(prp_id, threshold,  alignment, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id        ! Property list identifier
  INTEGER(HSIZE_T), INTENT(OUT) :: threshold  ! Threshold value
  INTEGER(HSIZE_T), INTENT(OUT) :: alignment  ! Alignment value
  INTEGER, INTENT(OUT) :: hdferr              ! Error code
                                              ! 0 on success and -1 on failure
END SUBROUTINE h5pget_alignment_f
	

Name: H5Pget_alloc_time
Signature:
herr_t H5Pget_alloc_time(hid_t plist_id, H5D_alloc_time_t *alloc_time )
Purpose:
Retrieves the timing for storage space allocation.
Description:
H5Pget_alloc_time retrieves the timing for allocating storage space for a dataset's raw data. This property is set in the dataset creation property list plist_id.

The timing setting is returned in alloc_time as one of the following values:
     H5D_ALLOC_TIME_DEFAULT   Uses the default allocation time, based on the dataset storage method.
See the alloc_time description in H5Pset_alloc_time for default allocation times for various storage methods.
H5D_ALLOC_TIME_EARLY All space is allocated when the dataset is created.
H5D_ALLOC_TIME_INCR   Space is allocated incrementally as data is written to the dataset.
H5D_ALLOC_TIME_LATE All space is allocated when data is first written to the dataset.

Note:
H5Pget_alloc_time is designed to work in concert with the dataset fill value and fill value write time properties, set with the functions H5Pget_fill_value and H5Pget_fill_time.
Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_alloc_time_f
SUBROUTINE h5pget_alloc_time_f(plist_id, flag, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id   ! Dataset creation
                                           ! property list identifier
  INTEGER(HSIZE_T), INTENT(OUT) :: flag    ! Allocation time flag
                                           ! Possible values are:
                                           !    H5D_ALLOC_TIME_ERROR_F
                                           !    H5D_ALLOC_TIME_DEFAULT_F
                                           !    H5D_ALLOC_TIME_EARLY_F
                                           !    H5D_ALLOC_TIME_LATE_F
                                           !    H5D_ALLOC_TIME_INCR_F
  INTEGER, INTENT(OUT)       :: hdferr     ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pget_alloc_time_f
	
History:

Name: H5Pget_attr_creation_order
Signature:
herr_t H5Pget_attr_creation_order( hid_t ocpl_id, unsigned *crt_order_flags )

Purpose:
Retrieves tracking and indexing settings for attribute creation order.

Description:
H5Pget_attr_creation_order retrieves the settings for tracking and indexing attribute creation order on an object.

ocpl_id is a dataset or group creation property list identifier. The term ocpl, for object creation property list, is used when different types of objects may be involved.

crt_order_flags returns flags with the following meanings:
     H5P_CRT_ORDER_TRACKED Attribute creation order is tracked but not necessarily indexed.
     H5P_CRT_ORDER_INDEXED     Attribute creation order is indexed (requires H5P_CRT_ORDER_TRACKED).
If crt_order_flags is returned with a value of 0 (zero), attribute creation order is neither tracked nor indexed.

Parameters:
hid_t ocpl_id IN: Object (group or dataset) creation property list identifier
unsigned *crt_order_flags     OUT: Flags specifying whether to track and index attribute creation order

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_attr_creation_order_f
SUBROUTINE h5pget_attr_creation_order_f(ocpl_id, crt_order_flags, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: ocpl_id   ! Object (group or dataset) creation 
                                          ! property list identifier 
  INTEGER, INTENT(OUT) :: crt_order_flags ! Flags specifying whether to track 
                                          ! and index attribute creation order 
  INTEGER, INTENT(OUT) :: hdferr          ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pget_attr_creation_order_f
  
    

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_attr_phase_change
Signature:
herr_t H5Pget_attr_phase_change( hid_t ocpl_id, unsigned *max_compact, unsigned *min_dense )

Purpose:
Retrieves attribute storage phase change thresholds.

Description:
H5Pget_attr_phase_change retrieves threshold values for attribute storage on an object. These thresholds determine the point at which attribute storage changes from compact storage (i.e., storage in the object header) to dense storage (i.e., storage in a heap and indexed with a B-tree).

In the general case, attributes are initially kept in compact storage. When the number of attributes exceeds max_compact, attribute storage switches to dense storage. If the number of attributes subsequently falls below min_dense, the attributes are returned to compact storage.

If max_compact is set to 0 (zero), dense storage always used.

ocpl_id is a dataset or group creation property list identifier. The term ocpl, for object creation property list, is used when different types of objects may be involved.

Parameters:
hid_t ocpl_id IN: Object (dataset or group) creation property list identifier
unsigned *max_compact   OUT: Maximum number of attributes to be stored in compact storage
(Default: 8)
unsigned *min_dense     OUT: Minimum number of attributes to be stored in dense storage
(Default: 6)

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_attr_phase_change_f
SUBROUTINE h5pget_attr_phase_change_f(ocpl_id, max_compact, min_dense, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: ocpl_id 
                  ! Object (dataset or group) creation property list identifier
  INTEGER, INTENT(OUT) :: max_compact  
                  ! Maximum number of attributes to be stored in compact storage
                  ! (Default: 8)
  INTEGER, INTENT(OUT) :: min_dense  
                  ! Minimum number of attributes to be stored in dense storage
                  ! (Default: 6)
  INTEGER, INTENT(OUT) :: hdferr  
                  ! Error code:
                  ! 0 on success and -1 on failure
END SUBROUTINE h5pget_attr_phase_change_f
    

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_btree_ratios
Signature:
herr_t H5Pget_btree_ratios(hid_t plist, double *left, double *middle, double *right )
Purpose:
Gets B-tree split ratios for a dataset transfer property list.
Description:
H5Pget_btree_ratios returns the B-tree split ratios for a dataset transfer property list.

The B-tree split ratios are returned through the non-NULL arguments left, middle, and right, as set by the H5Pset_btree_ratios function.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_btree_ratios_f
SUBROUTINE h5pget_btree_ratios_f(prp_id, left, middle, right, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  
                                  ! Property list identifier
  REAL, INTENT(OUT) :: left       ! B-tree split ratio for left-most nodes
  REAL, INTENT(OUT) :: middle     ! B-tree split ratio for all other nodes
  REAL, INTENT(OUT) :: right      ! The B-tree split ratio for right-most
                                  ! nodes and lone nodes.
  INTEGER, INTENT(OUT) :: hdferr  ! Error code:
                                  ! 0 on success and -1 on failure
END SUBROUTINE h5pget_btree_ratios_f
	

Name: H5Pget_buffer
Signature:
hsize_t H5Pget_buffer(hid_t plist, void **tconv, void **bkg )
Purpose:
Reads buffer settings.
Description:
H5Pget_buffer reads values previously set with H5Pset_buffer.
Parameters:
Returns:
Returns buffer size, in bytes, if successful; otherwise 0 on failure.
Fortran90 Interface: h5pget_buffer_f
SUBROUTINE h5pget_buffer_f(plist_id, size, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN)    :: plist_id ! Dataset transfer 
                                            ! property list identifier
  INTEGER(HSIZE_T), INTENT(OUT) :: size     ! Conversion buffer size
  INTEGER, INTENT(OUT)          :: hdferr   ! Error code
                                            ! 0 on success and -1 on failure
END SUBROUTINE h5pget_buffer_f
	
History:

Name: H5Pget_cache
Signature:
herr_t H5Pget_cache(hid_t plist_id, int *mdc_nelmts, size_t *rdcc_nelmts, size_t *rdcc_nbytes, double *rdcc_w0 )
Purpose:
Queries the raw data chunk cache parameters.
Description:
H5Pget_cache retrieves the maximum possible number of elements in the raw data chunk cache, the maximum possible number of bytes in the raw data chunk cache, and the preemption policy value.

Any (or all) arguments may be null pointers, in which case the corresponding datum is not returned.

Note that the *mdc_nelmts parameter is no longer used.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_cache_f
SUBROUTINE h5pget_cache_f(prp_id, mdc_nelmts, rdcc_nelmts, rdcc_nbytes,
                          rdcc_w0, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id         ! Property list identifier
  INTEGER, INTENT(OUT) :: mdc_nelmts           ! Number of elements (objects)
                                               ! in the meta data cache
  INTEGER(SIZE_T), INTENT(OUT) :: rdcc_nelmts  ! Number of elements (objects)
                                               ! in the meta data cache
  INTEGER(SIZE_T), INTENT(OUT) :: rdcc_nbytes  ! Total size of the raw data
                                               ! chunk cache, in bytes
  REAL, INTENT(OUT) :: rdcc_w0                 ! Preemption policy
  INTEGER, INTENT(OUT) :: hdferr               ! Error code
                                               ! 0 on success and -1 on failure
END SUBROUTINE h5pget_cache_f
	
History:

Last modified: 24 September 2014
Name: H5Pget_char_encoding
Signature:
herr_t H5Pget_char_encoding( hid_t plist_id, H5T_cset_t* encoding )

Purpose:
Retrieves the character encoding used to create a link or attribute name.

Description:
H5Pget_char_encoding retrieves the character encoding used to encode link or attribute names that are created with the property list plist_id.

Valid values for encoding are defined in H5Tpublic.h and include the following:
     H5T_CSET_ASCII US ASCII
     H5T_CSET_UTF8     UTF-8 Unicode encoding

Note that H5Pget_char_encoding retrieves the character set used for an HDF5 link or attribute name while H5Tget_cset retrieves the character set used in a character or string datatype.

Parameters:
hid_t plist_id IN: Link creation or attribute creation property list identifier
H5T_cset_t encoding     OUT: String encoding character set

Returns:
Returns a non-negative valule if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_char_encoding_f
SUBROUTINE h5pget_char_encoding_f(plist_id, encoding, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id 
                                   ! Property list identifier
  INTEGER, INTENT(OUT) :: encoding ! Valid values for encoding are:
                                   !  H5T_CSET_ASCII_F -> US ASCII
                                   !  H5T_CSET_UTF8_F -> UTF-8 Unicode encoding
  INTEGER, INTENT(OUT) :: hdferr   ! Error code:
                                   ! 0 on success and -1 on failure
END SUBROUTINE h5pget_char_encoding_f
        
See Also:
H5Pset_char_encoding
“Using UTF-8 Encoding in HDF5 Applications”

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_chunk
Signature:
int H5Pget_chunk(hid_t plist, int max_ndims, hsize_t * dims )
Purpose:
Retrieves the size of chunks for the raw data of a chunked layout dataset.
Description:
H5Pget_chunk retrieves the size of chunks for the raw data of a chunked layout dataset. This function is only valid for dataset creation property lists. At most, max_ndims elements of dims will be initialized.
Parameters:
Returns:
Returns chunk dimensionality if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_chunk_f
SUBROUTINE h5pget_chunk_f(prp_id, ndims, dims, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier 
  INTEGER, INTENT(IN) :: ndims          ! Number of chunk dimensions 
                                        ! to return
  INTEGER(HSIZE_T), DIMENSION(ndims), INTENT(OUT) :: dims    
                                        ! Array containing sizes of
                                        ! chunk dimensions
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! chunk rank on success 
                                        ! and -1 on failure
END SUBROUTINE h5pget_chunk_f
	

Last modified: 8 May 2009
Name: H5Pget_chunk_cache
Signature:
herr_t H5Pget_chunk_cache( hid_t dapl_id, size_t *rdcc_nslots, size_t *rdcc_nbytes, double *rdcc_w0 )

Purpose:
Retrieves the raw data chunk cache parameters.

Description:
H5Pget_chunk_cache retrieves the number of chunk slots in the raw data chunk cache hash table , the maximum possible number of bytes in the raw data chunk cache, and the preemption policy value.

These values are retrieved from a dataset access property list. If the values have not been set on the property list, then values returned will be the corresponding values from a default file access property list.

Any (or all) pointer arguments may be null pointers, in which case the corresponding datua is not returned.

Parameters:
hid_t plist_id      IN: Dataset access property list identifier.
size_t *rdcc_nslots   OUT: Number of chunk slots in the raw data chunk cache hash table.
size_t *rdcc_nbytes   OUT: Total size of the raw data chunk cache, in bytes.
double *rdcc_w0   OUT: Preemption policy.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Example Usage:
The following code retrieves the chunk cache settings on the dataset access property list dapl_id into local variables:
size_t nslots, nbytes;
double w0;
status = H5Pget_chunk_cache(dapl_id, &nslots, &nbytes, &w0);
Fortran90 Interface: h5pget_chunk_cache_f
  SUBROUTINE h5pget_chunk_cache_f(dapl_id, rdcc_nslots, rdcc_nbytes, rdcc_w0, hdferr)
    IMPLICIT NONE
    INTEGER(HID_T), INTENT(IN) :: dapl_id       ! Dataset access property list identifier.
    INTEGER(SIZE_T), INTENT(OUT) :: rdcc_nslots ! Number of chunk slots in the raw data chunk 
                                                ! cache hash table.
    INTEGER(SIZE_T), INTENT(OUT) :: rdcc_nbytes ! Total size of the raw data chunk cache, in bytes. 
    REAL, INTENT(OUT) :: rdcc_w0                ! Preemption policy.
    INTEGER, INTENT(OUT) :: hdferr              ! error code
                                                ! 0 on success and -1 on failure
  END SUBROUTINE h5pget_chunk_cache_f
  

See Also:
H5Pset_chunk_cache

History:
Release     Change
1.8.3 C function introduced in this release.

Last modified: 7 April 2015
Name: H5Pget_class
Signature:
hid_t H5Pget_class(hid_t plist )

Purpose:
Returns the property list class identifier for a property list.

Description:
H5Pget_class returns the property list class identifier for the property list identified by the plist parameter.

Note that H5Pget_class returns a value of hid_t type, an internal HDF5 identifier, rather than directly returning a property list class. That identifier can then be used with either H5Pequal or H5Pget_class_name to determine which predefined HDF5 property list class H5Pget_class has returned.

A full list of valid predefined property list classes appears in the description of H5Pcreate.

Determining the HDF5 property list class name with H5Pequal requires a series of H5Pequal calls in an if-else sequence. An iterative sequence of H5Pequal calls can compare the identifier returned by H5Pget_class to members of the list of valid property list class names. A pseudo-code snippet might read as follows:

    plist_class_id = H5Pget_class (dsetA_plist);

    if H5Pequal (plist_class_id, H5P_OBJECT_CREATE) = TRUE;        
            [ H5P_OBJECT_CREATE is the property list class    ]
            [ returned by H5Pget_class.                        ]

        else if H5Pequal (plist_class_id, H5P_DATASET_CREATE) = TRUE;
            [ H5P_DATASET_CREATE is the property list class.  ]

        else if H5Pequal (plist_class_id, H5P_DATASET_XFER) = TRUE;
            [ H5P_DATASET_XFER is the property list class.    ]

        .
        .   [ Continuing the iteration until a match is found. ]
        .  

H5Pget_class_name returns the property list class name directly as a string:

    plist_class_id = H5Pget_class (dsetA_plist);
    plist_class_name = H5Pget_class_name (plist_class_id) 
        

Note that frequent use of H5Pget_class_name can become a performance problem in a high-performance environment. The H5Pequal approach is generally much faster.

Parameters:
hid_t plist     IN: Identifier of property list to query.

Returns:
Returns a property list class identifier if successful. Otherwise returns a negative value.

Fortran90 Interface: h5pget_class_f
SUBROUTINE h5pget_class_f(prp_id, classtype, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier 
  INTEGER, INTENT(OUT) :: classtype    ! The type of the property list 
                                       ! to be created 
  INTEGER, INTENT(OUT) :: hdferr       ! Error code
                                       ! 0 on success and -1 on failure
END SUBROUTINE h5pget_class_f
    

History:
Release     Change
1.6.0 Return type changed in this release.
1.8.15 Updated the Fortran subroutine.

Last modified: 7 April 2015

Name: H5Pget_class_name

Purpose:
Retrieves the name of a class.

Signature:
char * H5Pget_class_name( hid_t pcid )

Description:
H5Pget_class_name retrieves the name of a generic property list class. The pointer to the name must be freed by the user after each successful call.

H5Pget_class_name
Returns this Class Name (Class Identifier)
Property List
Class
Expanded Name of the
Property List Class
The Class Identifier Used
with H5Pcreate
Comments
attribute create acpl Attribute Creation Property List H5P_ATTRIBUTE_CREATE  
dataset access dapl Dataset Access Property List H5P_DATASET_ACCESS  
dataset create dcpl Dataset Creation Property List H5P_DATASET_CREATE  
data transfer dxpl Data Transfer Property List H5P_DATASET_XFER  
datatype access     H5P_DATATYPE_ACCESS This class can be created, but there
are no properties in the class currently.
datatype create     H5P_DATATYPE_CREATE This class can be created, but there
are no properties in the class currently.
file access fapl File Access Property List H5P_FILE_ACCESS  
file create fcpl File Creation Property List H5P_FILE_CREATE  
file mount fmpl File Mount Property List H5P_FILE_MOUNT  
group access     H5P_GROUP_ACCESS This class can be created, but there
are no properties in the class currently.
group create gcpl Group Creation Property List H5P_GROUP_CREATE  
link access lapl Link Access Property List H5P_LINK_ACCESS  
link create lcpl Link Creation Property List H5P_LINK_CREATE  
object copy ocpypl Object Copy Property List H5P_OBJECT_COPY  
object create ocpl Object Creation Property List H5P_OBJECT_CREATE  
string create strcpl String Creation Property List H5P_STRING_CREATE  

Parameters:

Returns:
Success:  a pointer to an allocated string containing the class name
Failure:  NULL

Fortran90 Interface: h5pget_class_name_f
SUBROUTINE h5pget_class_name_f(prp_id, name, size, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id     ! Property list identifier to
                                           ! query
  INTEGER, INTENT(OUT) :: size             ! Actual length of the class name
                                           !  NOTE: If provided buffer "name" is smaller,
                                           !  than name will be truncated to fit into
                                           !  provided user buffer.
  CHARACTER(LEN=*), INTENT(INOUT) :: name  ! Buffer to retrieve class name
  INTEGER, INTENT(OUT) :: hdferr           ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pget_class_name_f
	
See Also:
H5Pcreate

History:
Release Change
1.8.15 Fortran subroutine was updated.
Class name table was added to the Description.




Name: H5Pget_class_parent
Signature:
hid_t H5Pget_class_parent( hid_t pcid )
Purpose:
Retrieves the parent class of a property class.
Description:
H5Pget_class_parent retrieves an identifier for the parent class of a property class.
Parameters:
Returns:
Success: a valid parent class object identifier
Failure: a negative value
Fortran90 Interface: h5pget_class_parent_f
SUBROUTINE h5pget_class_parent_f(prp_id, parent_id, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id     ! Property list identifier 
  INTEGER(HID_T), INTENT(OUT) :: parent_id ! Parent class property list 
                                           ! identifier
  INTEGER, INTENT(OUT) :: hdferr           ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pget_class_parent_f
	

Last modified: 17 August 2010
Name: H5Pget_copy_object
Signature:
herr_t H5Pget_copy_object( hid_t ocp_plist_id, unsigned *copy_options )

Purpose:
Retrieves the properties to be used when an object is copied.

Description:
H5Pget_copy_object retrieves the properties currently specified in the object copy property list ocp_plist_id, which will be invoked when a new copy is made of an existing object.

copy_options is a bit map indicating the flags, or properties, governing object copying that are set in the property list ocp_plist_id.

The available flags are described in H5Pset_copy_object.

Parameters:
hid_t ocp_plist_id IN: Object copy property list identifier
unsigned *copy_options     OUT: Copy option(s) set in the object copy property list

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_copy_object_f
  SUBROUTINE h5pget_copy_object_f(ocp_plist_id, copy_options, hdferr)
    IMPLICIT NONE 
    INTEGER(HID_T), INTENT(IN) :: ocp_plist_id 
                                         ! Object copy property list identifier
    INTEGER, INTENT(OUT) :: copy_options ! Valid copy options returned are:
                                         !   H5O_COPY_SHALLOW_HIERARCHY_F
                                         !   H5O_COPY_EXPAND_SOFT_LINK_F
                                         !   H5O_COPY_EXPAND_EXT_LINK_F
                                         !   H5O_COPY_EXPAND_REFERENCE_F
                                         !   H5O_COPY_WITHOUT_ATTR_FLAG_F
    INTEGER, INTENT(OUT) :: hdferr       ! Error code
    

History:
Release     C
1.8.0 Function introduced in this release.
1.8.3 Fortran subroutine introduced in this release.

Last modified: 2 May 2014

Name: H5Pget_core_write_tracking

Signature:
herr_t H5Pget_core_write_tracking(hid_t fapl_id, hbool_t *is_enabled, size_t *page_size)

Purpose:
Gets information about the write tracking feature used by the core VFD.

Description:
When a file is created or opened for writing using the core virtual file driver (VFD) with the backing store option turned on, the VFD can be configured to track changes to the file and only write out the modified bytes. To avoid a large number of small writes, the changes can be aggregated into pages of a user-specified size. The core VFD is also known as the memory VFD. The driver identifier is H5FD_CORE.

Notes:
This function is only for use with the core VFD and must be used after the call to H5Pset_fapl_core. It is an error to use this function with any other VFD.

This function only applies to the backing store write operation which typically occurs when the file is flushed or closed. This function has no relationship to the increment parameter passed to H5Pset_fapl_core.

For optimum performance, the page_size parameter should be a power of two.


Parameters:
hid_t fapl_id IN: File access property list identifier.
hbool_t *is_enabled OUT: Whether the feature is enabled.
size_t *page_size OUT: Size, in bytes, of write aggregation pages.

Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Fortran Interface:
None

See Also:
H5Pset_core_write_tracking

History:
Release Change
1.8.13 C function introduced with this release.




Last modified: 11 May 2011
Name: H5Pget_create_intermediate_group
Signature:
herr_t H5Pget_create_intermediate_group( hid_t lcpl_id, unsigned *crt_intermed_group )

Purpose:
Determines whether property is set to enable creating missing intermediate groups.

Description:
H5Pget_create_intermediate_group determines whether the link creation property list lcpl_id is set to allow functions that create objects in groups different from the current working group to create intermediate groups that may be missing in the path of a new or moved object.

Functions that create objects in or move objects to a group other than the current working group make use of this property. H5Gcreate_anon and H5Lmove are examples of such functions.

If crt_intermed_group is true, missing intermediate groups will be created; if crt_intermed_group is false, missing intermediate groups will not be created.

Parameters:
hid_t lcpl_id IN: Link creation property list identifier
unsigned *crt_intermed_group     OUT: Flag specifying whether to create intermediate groups upon creation of an object

Returns:
Returns a non-negative valule if successful; otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_data_transform
Signature:
ssize_t H5Pget_data_transform (hid_t plist_id, char *expression, size_t size)
Purpose:
Retrieves a data transform expression.
Description:
H5Pget_data_transform retrieves the data transform expression previously set in the dataset transfer property list plist_id by H5Pset_data_transform.

H5Pget_data_transform can be used to both retrieve the transform expression and to query its size.

If expression is non-NULL, up to size bytes of the data transform expression are written to the buffer. If expression is NULL, size is ignored and the function does not write anything to the buffer. The function always returns the size of the data transform expression.

If 0 is returned for the size of the expression, no data transform expression exists for the property list.

If an error occurs, the buffer pointed to by expression is unchanged and the function returns a negative value.

Parameters:
Returns:
Success: size of the transform expression.
Failure: a negative value.
Fortran90 Interface: h5pget_data_transform_f
SUBROUTINE h5pget_data_transform_f(plist_id, expression, hdferr, size)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id 
                                     ! Identifier of the property list or class
  CHARACTER(LEN=*), INTENT(OUT) :: expression  
                                     ! Buffer to hold transform expression
  INTEGER(SIZE_T), INTENT(OUT), OPTIONAL :: size 
                                     ! Registered size for transform expression
  INTEGER, INTENT(OUT) :: hdferr     ! Error code
                                     ! 0 on success and -1 on failure
END SUBROUTINE h5pget_data_transform_f
        
History:
Release     C
1.8.0 Function introduced in this release.

Last modified: 21 November 2011
Name: H5Pget_driver
Signature:
hid_t H5Pget_driver( hid_t plist_id )

Purpose:
Returns low-lever driver identifier.

Description:
H5Pget_driver returns the identifier of the low-level file driver associated with the file access property list or data transfer property list plist_id.

Valid driver identifiers distributed with HDF5 are listed and described in the following table.

Supported file drivers in HDF5

Driver
Name
  Driver
Identifier
  Description   Related API

POSIX   H5FD_SEC2   This driver uses POSIX file-system functions like read and write to perform I/O to a single, permanent file on local disk with no system buffering. This driver is POSIX-compliant and is the default file driver for all systems.   H5Pset_fapl_sec2

Direct   H5FD_DIRECT   This is the H5FD_SEC2 driver except data is written to or read from the file synchronously without being cached by the system.   H5Pset_fapl_direct

Log   H5FD_LOG   This is the H5FD_SEC2 driver with logging capabilities.   H5Pset_fapl_log

Windows   H5FD_WINDOWS   This driver was modified in HDF5-1.8.8 to be a wrapper of the POSIX driver, H5FD_SEC2. This change should not affect user applications.   H5Pset_fapl_windows

STDIO   H5FD_STDIO   This driver uses functions from the standard C stdio.h to perform I/O to a single, permanent file on local disk with additional system buffering.   H5Pset_fapl_stdio

Memory   H5FD_CORE   With this driver, an application can work with a file in memory for faster reads and writes. File contents are kept in memory until the file is closed. At closing, the memory version of the file can be written back to disk or abandoned.   H5Pset_fapl_core

Family   H5FD_FAMILY   With this driver, the HDF5 file’s address space is partitioned into pieces and sent to separate storage files using an underlying driver of the user’s choice. This driver is for systems that do not support files larger than 2 gigabytes.   H5Pset_fapl_family

Multi   H5FD_MULTI   With this driver, data can be stored in multiple files according to the type of the data. I/O might work better if data is stored in separate files based on the type of data. The Split driver is a special case of this driver.   H5Pset_fapl_multi

Split   H5FD_SPLIT   This file driver splits a file into two parts. One part stores metadata, and the other part stores raw data. This splitting a file into two parts is a limited case of the Multi driver.   H5Pset_fapl_split

Parallel   H5FD_MPIO   This is the standard HDF5 file driver for parallel file systems. This driver uses the MPI standard for both communication and file I/O.   H5Pset_fapl_mpio

Parallel POSIX   H5FD_MPIPOSIX   This driver is no longer available.    

Stream   H5FD_STREAM   This driver is no longer available.    

This list does not include custom drivers that might be defined and registered by a user.

The returned driver identifier is only valid as long as the file driver remains registered.

Parameters:
hid_t plist_id     IN: File access or data transfer property list identifier.

Returns:
Returns a valid low-level driver identifier if successful. Otherwise returns a negative value.

Fortran90 Interface: h5pget_driver_f
SUBROUTINE h5pget_driver_f(prp_id, driver, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier
  INTEGER, INTENT(OUT) :: driver       ! Low-level file driver identifier
  INTEGER, INTENT(OUT) :: hdferr       ! Error code
                                       ! 0 on success and -1 on failure
END SUBROUTINE h5pget_driver_f
    

History:
Release     C
1.4.0 Function introduced in this release.

Name: H5Pget_driver_info
Signature:
void *H5Pget_driver_info( hid_t plist_id )

Purpose:
Returns a pointer to file driver information.

Description:
H5Pget_driver_info returns a pointer to file driver-specific information for the low-level driver associated with the file access or data transfer property list plist_id.

The pointer returned by this function points to an “uncopied” struct. Driver-specific versions of that struct are defined for each low-level driver in the relevant source code file H5FD*.c. For example, the struct used for the MULTI driver is H5FD_multi_fapl_t defined in H5FDmulti.c.

If no driver-specific properties have been registered, H5Pget_driver_info returns NULL.

Note:
H5Pget_driver_info and H5Pset_driver are used only when creating a virtual file driver (VFD) in the virtual file layer (VFL). For further information, see “Virtual File Layer” and “List of VFL Functions” in the HDF5 Technical Notes.

Parameters:
hid_t plist_id
IN: File access or data transfer property list identifier.

Returns:
Returns a pointer to a struct containing low-level driver information. Otherwise returns NULL.

NULL is also returned if no driver-specific properties have been registered. No error is pushed on the stack in this case.

Non-C API(s):
None.

History:

Name: H5Pget_dxpl_mpio
Signature:
herr_t H5Pget_dxpl_mpio( hid_t dxpl_id, H5FD_mpio_xfer_t *xfer_mode )
Purpose:
Returns the data transfer mode.
Description:
H5Pget_dxpl_mpio queries the data transfer mode currently set in the data transfer property list dxpl_id.

Upon return, xfer_mode contains the data transfer mode, if it is non-null.

H5Pget_dxpl_mpio is not a collective function.

Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Fortran90 Interface: h5pget_dxpl_mpio_f
SUBROUTINE h5pget_dxpl_mpio_f(prp_id, data_xfer_mode, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id    ! Property list identifier
  INTEGER, INTENT(OUT) :: data_xfer_mode  ! Data transfer mode
                                          ! Possible values are:
                                          !    H5FD_MPIO_INDEPENDENT_F
                                          !    H5FD_MPIO_COLLECTIVE_F
  INTEGER, INTENT(OUT) :: hdferr          ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pget_dxpl_mpio_f
	
History:

Name: H5Pget_edc_check
Signature:
H5Z_EDC_t H5Pget_edc_check(hid_t plist)
Purpose:
Determines whether error-detection is enabled for dataset reads.
Description:
H5Pget_edc_check queries the dataset transfer property list plist to determine whether error detection is enabled for data read operations.
Parameters:
Returns:
Returns H5Z_ENABLE_EDC or H5Z_DISABLE_EDC if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_edc_check_f
SUBROUTINE h5pget_edc_check_f(prp_id, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Dataset transfer property list 
                                        ! identifier 
  INTEGER, INTENT(OUT)       :: flag    ! EDC flag; possible values
                                        !    H5Z_DISABLE_EDC_F 
                                        !    H5Z_ENABLE_EDC_F 
  INTEGER, INTENT(OUT)       :: hdferr  ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pget_edc_check_f
	
History:

Last modified: 26 April 2016

Name: H5Pget_efile_prefix

Signature:
ssize_t H5Pget_efile_prefix( hid_t dapl_id, const char *prefix, size_t size )

Purpose:
Retrieves the prefix for external raw data storage files as set in the dataset access property list.

Description:
H5Pget_efile_prefix retrieves the file system path prefix for locating external files associated with a dataset that uses external storage. This will be the value set with H5Pset_efile_prefix or the HDF5 Library’s default.

The value of size is the size in bytes of the prefix, including the NULL terminator. If the size is unknown, a preliminary H5Pget_elink_prefix call with the pointer prefix set to NULL will return the size of the prefix without the NULL terminator.

The prefix buffer must be allocated by the caller. In a call that retrieves the actual prefix, that buffer must be of the size specified in size.


Note:
See H5Pset_efile_prefix for a more complete description of file location behavior and for notes on the use of the HDF5_EXTFILE_PREFIX environment variable.

Parameters:
hid_t dapl_id   IN: Dataset access property list identifier
const char *prefix   IN/OUT: Dataset external storage prefix in UTF-8 or ASCII
(Path and filename must be ASCII on Windows systems.)
size_t size   IN: Size of prefix buffer in bytes

Returns:
Returns the size of prefix and the prefix string will be stored in prefix if successful.
Otherwise returns a negative value and the contents of prefix will be undefined.

Fortran Interface:
None

See Also:

History:
Release     Change
1.10.0 and 1.8.17    C function introduced in these releases.




Last modified: 8 May 2009
Name: H5Pget_elink_acc_flags
Signature:
herr_t H5Pget_elink_acc_flags( hid_t lapl_id, unsigned *flags )

Purpose:
Retrieves the external link traversal file access flag from the specified link access property list.

Description:
H5Pget_elink_acc_flags retrieves the file access flag used to open an external link target file from the specified link access property list.

The value returned, if it is not H5F_ACC_DEFAULT will override the default access flag, which is the access flag used to open the parent file.

Parameters:
hid_t lapl_id      IN: Link access property list identifier
unsigned *flags   OUT: File access flag for link traversal.

Valid values include:
  H5F_ACC_RDWR   Files opened through external links will be opened with write access.
  H5F_ACC_RDONLY   Files opened through external links will be opened with read-only access.
  H5F_ACC_DEFAULT   Files opened through external links will be opened with the same access flag as the parent file.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Example Usage:
The following code retrieves the external link access flag settings on the link access property list lapl_id into a local variable:
unsigned acc_flags;
status = H5Pget_elink_acc_flags(lapl_id, &acc_flags);

See Also:
H5Pset_elink_acc_flags

History:
Release     Change
1.8.3 C function introduced in this release.

Last modified: 17 August 2009
Name: H5Pget_elink_cb
Signature:
herr_t H5Pget_elink_cb( hid_t lapl_id, H5L_elink_traverse_t *func, void **op_data )

Purpose:
Retrieves the external link traversal callback function from the specified link access property list.

Description:
H5Pget_elink_cb retrieves the user-defined external link traversal callback function defined in the specified link access property list.

The callback function may adjust the file access property list and file access flag to use when opening a file through an external link. The callback will be executed by the HDF5 Library immediately before opening the target file.

Parameters:
hid_t lapl_id      IN: Link access property list identifier.
H5L_elink_traverse_t *func   OUT: User-defined external link traversal callback function.
void **op_data   OUT: User-defined input data for the callback function.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Failure Modes:
H5Pget_elink_cb will fail if the link access property list identifier, lapl_id, is invalid.

An invalid function pointer or data pointer, func or op_data respectively, may cause a segmentation fault or an invalid memory access.

Example Usage:
The following code retrieves the external link callback settings on the link access property list lapl_id into local variables:
H5L_elink_traverse_t elink_callback_func;
void *elink_callback_udata;
status = H5Pget_elink_cb(lapl_id, &elink_callback_func, &elink_callback_udata);

See Also:
H5Pset_elink_cb

H5Pset_elink_fapl,   H5Pset_elink_acc_flags,   H5Lcreate_external

H5Fopen for discussion of H5F_ACC_RDWR and H5F_ACC_RDONLY file access flags

H5L_elink_traverse_t

History:
Release     Change
1.8.3 C function introduced in this release.

Name: H5Pget_elink_fapl
Signature:
hid_t H5Pget_elink_fapl( hid_t lapl_id )

Purpose:
Retrieves the file access property list identifier associated with the link access property list.

Description:
H5Pget_elink_fapl retrieves the file access property list identifier that is set for the link access property list identifier, lapl_id. The library uses this file access property list identifier to open the target file for the external link access.

When no such identifier is set, this routine returns H5P_DEFAULT.

See also H5Pset_elink_fapl and H5Lcreate_external.

Parameters:
hid_t lapl_id      IN: Link access property list identifier.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     C
1.8.2 Function introduced in this release.

Last modified: 11 May 2011
Name: H5Pget_elink_file_cache_size
Signature:
herr_t H5Pget_elink_file_cache_size( hid_t fapl_id, unsigned *efc_size )

Purpose:
Retrieves the size of the external link open file cache.

Description:
H5Pget_elink_file_cache_size retrieves the number of files that can be held open in an external link open file cache.

Parameters:
hid_t fapl_id      IN: File access property list identifier
unsigned *efc_size   OUT: External link open file cache size in number of files.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Example Usage:
The following code retrieves the size of the external link open file cache in the local variable efc_size:
    status = H5Pget_elink_file_cache_size(fapl_id, &efc_size);   

See Also:
H5Pset_elink_file_cache_size
H5Fclear_elink_file_cache

History:
Release     Change
1.8.7 C function introduced in this release.

Name: H5Pget_elink_prefix
Signature:
ssize_t H5Pget_elink_prefix( hid_t lapl_id, char *prefix, size_t size )

Purpose:
Retrieves prefix applied to external link paths.

Description:
H5Pget_elink_prefix retrieves the prefix applied to the path of any external links traversed.

When an external link is traversed, the prefix is retrieved from the link access property list lapl_id, returned in the user-allocated buffer pointed to by prefix, and prepended to the filename stored in the external link.

The size in bytes of the prefix, including the NULL terminator, is specified in size. If size is unknown, a preliminary H5Pget_elink_prefix call with the pointer prefix set to NULL will return the size of the prefix without the NULL terminator.

Parameters:
hid_t lapl_id IN: Link access property list identifier
char *prefix     OUT: Prefix applied to external link paths
size_t size IN: Size of prefix, including null terminator

Returns:
If successful, returns a non-negative value specifying the size in bytes of the prefix without the NULL terminator; otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_est_link_info
Signature:
herr_t H5Pget_est_link_info( hid_t gcpl_id, unsigned *est_num_entries, unsigned *est_name_len )

Purpose:
Queries data required to estimate required local heap or object header size.

Description:
H5Pget_est_link_info queries a group creation property list, gcpl_id, for its “estimated number of links” and “estimated average name length” settings.

The estimated number of links anticipated to be inserted into a group created with this property list is returned in est_num_entries.

The estimated average length of the anticipated link names is returned in est_name_len.

The values for these two settings are multiplied to compute the initial local heap size (for old-style groups, if the local heap size hint is not set) or the initial object header size for (new-style compact groups; see “Group implementations in HDF5”). Accurately setting these parameters will help reduce wasted file space.

A value of 0 (zero) in est_num_entries will prevent a group from being created in the compact format.

See “Group implementations in HDF5” in the H5G API introduction for a discussion of the available types of HDF5 group structures.

Parameters:
hid_t gcpl_id IN: Group creation property list identifier
unsigned *est_num_entries     OUT: Estimated number of links to be inserted into group
unsigned *est_name_len OUT: Estimated average length of link names
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_est_link_info_f
SUBROUTINE h5pget_est_link_info_f(gcpl_id,est_num_entries, est_name_len,hdferr)

  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: gcpl_id   ! Group creation property list id
  INTEGER, INTENT(OUT) :: est_num_entries ! Estimated number of links to be 
                                          ! inserted into group
  INTEGER, INTENT(OUT) :: est_name_len    ! Estimated average length of link 
                                          ! names
  INTEGER, INTENT(OUT) :: hdferr          ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pget_est_link_info_f 
        

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_external
Signature:
herr_t H5Pget_external(hid_t plist, unsigned idx, size_t name_size, char *name, off_t *offset, hsize_t *size )

Purpose:
Returns information about an external file.

Description:
H5Pget_external returns information about an external file. The external file is specified by its index, idx, which is a number from zero to N-1, where N is the value returned by H5Pget_external_count. At most name_size characters are copied into the name array. If the external file name is longer than name_size with the null terminator, the return value is not null terminated (similar to strncpy()).

If name_size is zero or name is the null pointer, the external file name is not returned. If offset or size are null pointers then the corresponding information is not returned.

Parameters:

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_external_f
SUBROUTINE h5pget_external_f(prp_id, idx, name_size, name, offset,bytes, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id     ! Property list identifier
  INTEGER, INTENT(IN) :: idx               ! External file index.
  INTEGER(SIZE_T), INTENT(IN) :: name_size ! Maximum length of name array
  CHARACTER(LEN=*), INTENT(OUT) :: name    ! Name of an external file
  INTEGER, INTENT(OUT) :: offset           ! Offset, in bytes, from the 
                                           ! beginning of the file to the 
                                           ! location in the file where
                                           ! the data starts.
  INTEGER(HSIZE_T), INTENT(OUT) :: bytes   ! Number of bytes reserved in 
                                           ! the file for the data
  INTEGER, INTENT(OUT) :: hdferr           ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pget_external_f
    

History:

Name: H5Pget_external_count
Signature:
int H5Pget_external_count(hid_t plist )
Purpose:
Returns the number of external files for a dataset.
Description:
H5Pget_external_count returns the number of external files for the specified dataset.
Parameters:
Returns:
Returns the number of external files if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_external_count_f
SUBROUTINE h5pget_external_count_f (prp_id, count, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier
  INTEGER, INTENT(OUT) :: count        ! Number of external files for 
                                       ! the specified dataset
  INTEGER, INTENT(OUT) :: hdferr       ! Error code
                                       ! 0 on success and -1 on failure
END SUBROUTINE h5pget_external_count_f
	

Name: H5Pget_family_offset
Signature:
herr_t H5Pget_family_offset ( hid_t fapl_id, hsize_t *offset )
Purpose:
Retrieves a data offset from the file access property list.
Description:
H5Pget_family_offset retrieves the value of offset from the file access property list fapl_id so that the user application can retrieve a file handle for low-level access to a particular member of a family of files. The file handle is retrieved with a separate call to H5Fget_vfd_handle (or, in special circumstances, to H5FDget_vfd_handle; see Virtual File Layer and List of VFL Functions in HDF5 Technical Notes).

The data offset returned in offset is the offset of the data in the HDF5 file that is stored on disk in the selected member file in a family of files.

Use of this function is only appropriate for an HDF5 file written as a family of files with the FAMILY file driver.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface:
None.
History:

Name: H5Pget_fapl_core
Signature:
herr_t H5Pget_fapl_core( hid_t fapl_id, size_t *increment, hbool_t *backing_store )
Purpose:
Queries core file driver properties.
Description:
H5Pget_fapl_core queries the H5FD_CORE driver properties as set by H5Pset_fapl_core.
Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Fortran90 Interface: h5pget_fapl_core_f
SUBROUTINE h5pget_fapl_core_f(prp_id, increment, backing_store, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN)  :: prp_id     ! Property list identifier
  INTEGER(SIZE_T), INTENT(OUT) :: increment ! File block size in bytes
  LOGICAL, INTENT(OUT) :: backing_store     ! Flag to indicate that entire
                                            ! file contents are flushed to 
                                            ! a file with the same name as 
                                            ! this core file
  INTEGER, INTENT(OUT) :: hdferr            ! Error code
                                            ! 0 on success and -1 on failure
END SUBROUTINE h5pget_fapl_core_f
	
History:

Name: H5Pget_fapl_direct
Signature:
herr_t H5Pget_fapl_direct( hid_t fapl_id, size_t *alignment, size_t *block_size, size_t *cbuf_size )

Purpose:
Retrieves direct I/O driver settings.

Description:
H5Pget_fapl_direct retrieves the required memory alignment (alignment), file system block size (block_size), and copy buffer size (cbuf_size) settings for the direct I/O driver, H5FD_DIRECT, from the file access property list fapl_id.

See H5Pset_fapl_direct for discussion of these values, requirements, and important considerations.

Parameters:
hid_t fapl_id IN: File access property list identifier
size_t *alignment OUT: Required memory alignment boundary
size_t *block_size     OUT: File system block size
size_t *cbuf_size OUT: Copy buffer size

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
SUBROUTINE H5Pget_fapl_direct_f(fapl_id, alignment, block_size, cbuf_size, &
                                hdferr)
  IMPLICIT NONE  
  INTEGER(HID_T), INTENT(IN) :: fapl_id ! File access property list identifier
  INTEGER(SIZE_T), INTENT(OUT) :: alignment 	  
                                        ! Required memory alignment boundary!
  INTEGER(SIZE_T), INTENT(OUT) :: block_size     
                                        ! File system block size
  INTEGER(SIZE_T), INTENT(OUT) :: cbuf_size 	  
                                        ! Copy buffer size
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE H5Pget_fapl_direct_f
    

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_fapl_family
Signature:
herr_t H5Pget_fapl_family ( hid_t fapl_id, hsize_t *memb_size, hid_t *memb_fapl_id )
Purpose:
Returns file access property list information.
Description:
H5Pget_fapl_family returns file access property list for use with the family driver. This information is returned through the output parameters.
Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_fapl_family_f
SUBROUTINE h5pget_fapl_family_f(prp_id, imemb_size, memb_plist, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN)    :: prp_id    ! Property list identifier
  INTEGER(HSIZE_T), INTENT(OUT) :: memb_size ! Logical size, in bytes,
                                             ! of each family member
  INTEGER(HID_T), INTENT(OUT) :: memb_plist  ! Identifier of the file 
                                             ! access property list to be
                                             ! used for each family member
  INTEGER, INTENT(OUT) :: hdferr             ! Error code
                                             ! 0 on success and -1 on failure
END SUBROUTINE h5pget_fapl_family_f
	
History:

Last modified: 15 May 2009
Name: H5Pget_fapl_mpio
Signature:
herr_t H5Pget_fapl_mpio( hid_t fapl_id, MPI_Comm *comm, MPI_Info *info )

Purpose:
Returns MPI communicator information.

Description:
If the file access property list is set to the H5FD_MPIO driver, H5Pget_fapl_mpio returns duplicates of the stored MPI communicator and Info object through the comm and info pointers, if those values are non-null.

Since the MPI communicator and Info object are duplicates of the stored information, future modifications to the access property list will not affect them. It is the responsibility of the application to free these objects.

Parameters:

Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Fortran90 Interface: h5pget_fapl_mpio_f
SUBROUTINE h5pget_fapl_mpio_f(prp_id, comm, info, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier
  INTEGER, INTENT(OUT) :: comm         ! Buffer to return communicator 
  INTEGER, INTENT(IN) :: info          ! Buffer to return info object as
                                       ! defined in MPI_FILE_OPEN of MPI-2
  INTEGER, INTENT(OUT) :: hdferr       ! Error code
                                       ! 0 on success and -1 on failure
END SUBROUTINE h5pget_fapl_mpio_f
    

History:

Last modified: 2 May 2013
Name: H5Pget_fapl_mpiposix
Signature:
herr_t H5Pget_fapl_mpiposix( hid_t fapl_id, MPI_Comm *comm, hbool_t *use_gpfs_hints )

Purpose:
Returns MPI communicator information.

Function Removed:
The C functions H5Pset_fapl_mpiposix and H5Pset_fapl_mpiposix and the corresponding Fortran subroutines have been removed from the HDF5 Library at Release 1.8.13. They remain available in earlier releases, through HDF5 Release 1.8.12.

All applications used with HDF5 Release 1.8.13 or later and that use MPI I/O should use the functions H5Pset_fapl_mpio and H5Pget_fapl_mpio or the corresponding Fortran subroutines.

While HDF5’s MPI-POSIX driver (H5Pset_fapl_mpiposix and H5Pget_fapl_mpiposix) once provided performance benefits on some systems, that is no longer the case. HDF5’s MPIO driver (H5Pset_fapl_mpio and H5Pget_fapl_mpio) now provides as good or better performance on all modern systems.

Description:
If the file access property list is set to the H5FD_MPIPOSIX driver, H5Pget_fapl_mpiposix returns the MPI communicator through the comm pointer, if those values are non-null.

comm is not copied, so it is valid only until the file access property list is either modified or closed.

use_gpfs_hints specifies whether to attempt to use GPFS hints when accessing this file. A value of TRUE (or 1) indicates that the hints are being used, where possible. A value of FALSE (or 0) indicates that the hints are not being used.

Parameters:
hid_t fapl_id IN: File access property list identifier.
MPI_Comm *comm OUT: MPI-2 communicator.
hbool_t *use_gpfs_hints     OUT: Use of GPFS hints.

Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Fortran90 Interface: h5pget_fapl_mpiposix_f
SUBROUTINE h5pget_fapl_mpiposix_f(prp_id, comm, use_gpfs, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier
  INTEGER, INTENT(OUT) :: comm          ! Buffer to return communicator
  LOGICAL, INTENT(OUT) :: use_gpfs
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
END SUBROUTINE h5pget_fapl_mpiposix_f
	

History:
Release     Change
1.8.13 C function and Fortran subroutine removed from HDF5 at this release.
1.6.1 Fortran subroutine introduced.
1.6.0 use_gpfs_hints parameter added.
1.6.0 C function introduced in this release.

Name: H5Pget_fapl_multi
Signature:
herr_t H5Pget_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 )
Purpose:
Returns information about the multi-file access property list.
Description:
H5Pget_fapl_multi returns information about the multi-file access property list.
Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Fortran90 Interface: h5pget_fapl_multi_f
SUBROUTINE h5pget_fapl_multi_f(prp_id, memb_map, memb_fapl, memb_name,
                               memb_addr, relax, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T),INTENT(IN)   :: prp_id    ! Property list identifier

  INTEGER,DIMENSION(0:H5FD_MEM_NTYPES_F-1),INTENT(OUT)          :: memb_map
  INTEGER(HID_T),DIMENSION(0:H5FD_MEM_NTYPES_F-1),INTENT(OUT)   :: memb_fapl
  CHARACTER(LEN=*),DIMENSION(0:H5FD_MEM_NTYPES_F-1),INTENT(OUT) :: memb_name
  REAL, DIMENSION(0:H5FD_MEM_NTYPES_F-1), INTENT(OUT)           :: memb_addr
               ! Numbers in the interval [0,1) (e.g. 0.0 0.1 0.5 0.2 0.3 0.4)
               ! real address in the file will be calculated as X*HADDR_MAX 

  LOGICAL, INTENT(OUT) :: relax
  INTEGER, INTENT(OUT) :: hdferr           ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pget_fapl_multi_f
	
History:

Name: H5Pget_fclose_degree
Signature:
herr_t H5Pget_fclose_degree(hid_t fapl_id, H5F_close_degree_t *fc_degree)
Purpose:
Returns the file close degree.
Description:
H5Pget_fclose_degree returns the current setting of the file close degree property fc_degree in the file access property list fapl_id.

The value of fc_degree determines how aggressively H5Fclose deals with objects within a file that remain open when H5Fclose is called to close that file. fc_degree can have any one of four valid values as described in H5Pset_fclose_degree.

Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Fortran90 Interface: h5pget_fclose_degree_f
SUBROUTINE h5pget_fclose_degree_f(fapl_id, degree, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: fapl_id ! File access property list identifier
  INTEGER, INTENT(OUT) :: degree        ! Info about file close behavior
                                        ! Possible values:
                                        !    H5F_CLOSE_DEFAULT_F
                                        !    H5F_CLOSE_WEAK_F
                                        !    H5F_CLOSE_SEMI_F
                                        !    H5F_CLOSE_STRONG_F
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pget_fclose_degree_f
	
History:

Last modified: 5 May 2014
Name: H5Pget_file_image
Signature:
herr_t H5Pget_file_image( hid_t fapl_id, void **buf_ptr_ptr, size_t *buf_len_ptr )

Purpose:
Retrieves a copy of the file image designated as the initial content and structure of a file.

Motivation:
H5Pget_file_image and other HDF5 elements are used to load an image of an HDF5 file into system memory and to open that image as a regular HDF5 file. An application can then work with the file without the overhead of disk I/O.

Essential Reading:
This function is part of the file image operations feature set. It is highly recommended to study the guide “HDF5 File Image Operations” before implementing software that works with such file images.

The “See Also” section below provides links to individual elements of HDF5 file image operations feature set.

Description:
H5Pget_file_image allows an application to retrieve a copy of the file image designated for a VFD to use as the initial contents of a file.

If file image callbacks are defined, H5Pget_file_image will use them when allocating and loading the buffer to return to the application (see H5Sset_file_image_callbacks). If file image callbacks are not defined, the function will use malloc and memcpy. When malloc and memcpy are used, it is the caller’s responsibility to discard the returned buffer with a call to free.

It is the responsibility of the calling application to free the buffer whose address is returned in buf_ptr_ptr. This can be accomplished with free if file image callbacks have not been set (see H5Pset_file_image_callbacks) or with the appropriate method if file image callbacks have been set.

Parameters:
hid_t fapl_id      IN: File access property list identifier.
void **buf_ptr_ptr   IN/OUT: On input, NULL or a pointer to a pointer to a buffer that contains the file image.

On successful return, if buf_ptr_ptr is not NULL, *buf_ptr_ptr will contain a pointer to a copy of the initial image provided in the last call to H5Pset_file_image for the supplied fapl_id. If no initial image has been set, *buf_ptr_ptr will be NULL.

size_t *buf_len_ptr   IN/OUT: On input, NULL or a pointer to a buffer specifying the required size of the buffer to hold the file image.

On successful return, if buf_len_ptr was not passed in as NULL, buf_len_ptr will return the required size in bytes of the buffer to hold the initial file image in the supplied file access property list, fapl_id. If no initial image is set, the value of *buf_len_ptr will be set to 0 (zero).

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran2003 Interface: h5pget_file_image_f

Signature:

  SUBROUTINE h5pget_file_image_f(fapl_id, buf_ptr, buf_len_ptr, hdferr)
    USE iso_c_binding
    IMPLICIT NONE
    INTEGER(HID_T) , INTENT(IN)                :: fapl_id
    TYPE(C_PTR)    , INTENT(OUT), DIMENSION(*) :: buf_ptr
    INTEGER(SIZE_T), INTENT(OUT)               :: buf_len_ptr
    INTEGER        , INTENT(OUT)               :: hdferr

Inputs:

  fapl_id     - File access property list identifier.

Outputs:

  buf_ptr     - Will hold either a C_NULL_PTR or a scalar of type
                c_loc. If buf_ptr is not C_NULL_PTR, on successful
                return, buf_ptr shall contain a C pointer to a copy
                of the initial image provided in the last call to
                H5Pset_file_image_f for the supplied fapl_id, or
                buf_ptr shall contain a C_NULL_PTR if there is no
                initial image set.

  buf_len_ptr - Contains the value of the buffer parameter for
                the initial image in the supplied fapl_id. The value
                will be 0 if no initial image is set.

  hdferr      - Returns 0 if successful and -1 if fails

See Also:
H5LTopen_file_image
 
H5Fget_file_image
 
H5Pset_file_image
 
H5Pset_file_image_callbacks
H5Pget_file_image_callbacks
     HDF5 File Image Operations
     in Advanced Topics in HDF5
 
Within H5Pset_file_image_callbacks:
Callback struct   H5_file_image_callbacks_t
Callback ENUM   H5_file_image_op_t

History:
Release     Change
1.8.13 Fortran subroutine added in this release.
1.8.9 C function introduced in this release.

Last modified: 17 April 2012
Name: H5Pget_file_image_callbacks
Signature:
herr_t H5Pget_file_image_callbacks( hid_t fapl_id, H5_file_image_callbacks_t *callbacks_ptr )

Purpose:
Retrieves callback routines for working with file images.

Motivation:
H5Pget_file_image_callbacks and other elements of HDF5 are used to load an image of an HDF5 file into system memory and open that image as a regular HDF5 file. An application can then use the file without the overhead of disk I/O.

Recommended Reading:
This function is part of the file image operations feature set. It is highly recommended to study the guide “HDF5 File Image Operations” before using this feature set.

See the “See Also” section below for links to other elements of HDF5 file image operations.

Description:
H5Pget_file_image_callbacks retrieves the callback routines set for working with file images opened with the file access property list fapl_id.

The callbacks must have been previously set with H5Pset_file_image_callbacks in the file access property list.

Upon the successful return of H5Pget_file_image_callbacks, the fields in the instance of the H5_file_image_callbacks_t struct pointed to by callbacks_ptr will contain the same values as were passed in the most recent H5Pset_file_image_callbacks call for the file access property list fapl_id.

Parameters:
hid_t fapl_id          IN: File access property list identifier.
H5_file_image_callbacks_t *callbacks_ptr
   IN/OUT: Pointer to the instance of the H5_file_image_callbacks_t struct in which the callback routines are to be returned.

Struct fields must be initialized to NULL before the call is made.

Struct field contents upon return will match those passed in in the last H5Pset_file_image_callbacks call for the file access property list fapl_id.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

See Also:
H5LTopen_file_image
 
H5Fget_file_image
 
H5Pset_file_image
H5Pget_file_image
 
H5Pset_file_image_callbacks
     HDF5 File Image Operations
     in Advanced Topics in HDF5
 
Within H5Pset_file_image_callbacks:
Callback struct   H5_file_image_callbacks_t
Callback ENUM   H5_file_image_op_t

History:
Release     Change
1.8.9 C function introduced in this release.

Name: H5Pget_fill_time
Signature:
herr_t H5Pget_fill_time(hid_t plist_id, H5D_fill_time_t *fill_time )
Purpose:
Retrieves the time when fill value are written to a dataset.
Description:
H5Pget_fill_time examines the dataset creation property list plist_id to determine when fill values are to be written to a dataset.

Valid values returned in fill_time are as follows:
     H5D_FILL_TIME_IFSET   Fill values are written to the dataset when storage space is allocated only if there is a user-defined fill value, i.e., one set with H5Pset_fill_value.   (Default)
  H5D_FILL_TIME_ALLOC   Fill values are written to the dataset when storage space is allocated.
  H5D_FILL_TIME_NEVER Fill values are never written to the dataset.

Note:
H5Pget_fill_time is designed to work in coordination with the dataset fill value and dataset storage allocation time properties, retrieved with the functions H5Pget_fill_value and H5Pget_alloc_time.
Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_fill_time_f
SUBROUTINE h5pget_fill_time_f(plist_id, flag, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id ! Dataset creation property 
                                         ! list identifier
  INTEGER(HSIZE_T), INTENT(OUT) :: flag  ! Fill time flag
                                         ! Possible values are:
                                         !    H5D_FILL_TIME_ERROR_F
                                         !    H5D_FILL_TIME_ALLOC_F
                                         !    H5D_FILL_TIME_NEVER_F
  INTEGER, INTENT(OUT)       :: hdferr   ! Error code
                                         ! 0 on success and -1 on failure
END SUBROUTINE h5pget_fill_time_f
	
History:

Last modified: 29 September 2011
Name: H5Pget_fill_value
Signature:
herr_t H5Pget_fill_value( hid_t plist_id, hid_t type_id, void *value )

Purpose:
Retrieves a dataset fill value.

Description:
H5Pget_fill_value returns the dataset fill value defined in the dataset creation property list plist_id.

The fill value is returned through the value pointer and will be converted to the datatype specified by type_id. This datatype may differ from the fill value datatype in the property list, but the HDF5 library must be able to convert between the two datatypes.

If the fill value is undefined, i.e., set to NULL in the property list, H5Pget_fill_value will return an error. H5Pfill_value_defined should be used to check for this condition before H5Pget_fill_value is called.

Memory must be allocated by the calling application.

Note:
H5Pget_fill_value is designed to coordinate with the dataset storage allocation time and fill value write time properties, which can be retrieved with the functions H5Pget_alloc_time and H5Pget_fill_time, respectively.

Parameters:
hid_t plist_id     IN: Dataset creation property list identifier.
hid_t type_id, IN: Datatype identifier for the value passed via value.
void *value OUT: Pointer to buffer to contain the returned fill value.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_fill_value_f
Signature:

  SUBROUTINE h5pget_fill_value_f(prp_id, type_id, fillvalue, hdferr)
    INTEGER(HID_T), INTENT(IN)  :: prp_id 
    INTEGER(HID_T), INTENT(IN)  :: type_id
    TYPE(VOID)    , INTENT(OUT) :: fillvalue
    INTEGER       , INTENT(OUT) :: hdferr

Inputs:

  prp_id    - Property list identifier
  type_id   - Datatype identifier of fill value datatype (in memory)

Outputs:

  fillvalue - Fillvalue
  hdferr    - Returns 0 if successful and -1 if fails

Fortran2003 Interface: h5pget_fill_value_f
Signature:

  SUBROUTINE h5pget_fill_value_f(prp_id, type_id, fillvalue, hdferr)
    INTEGER(HID_T), INTENT(IN)  :: prp_id 
    INTEGER(HID_T), INTENT(IN)  :: type_id
    TYPE(C_PTR)   , INTENT(OUT) :: fillvalue
    INTEGER       , INTENT(OUT) :: hdferr

Inputs:

  prp_id    - Property list identifier
  type_id   - Datatype identifier of fill value datatype (in memory)

Outputs:

  fillvalue - Fillvalue
  hdferr    - Returns 0 if successful and -1 if fails

History:
Release     Change
1.8.8 Fortran updated to Fortran2003.

Name: H5Pget_filter
Signatures:
H5Z_filter_t H5Pget_filter( hid_t plist, unsigned int idx, unsigned int *flags, size_t *cd_nelmts, unsigned int *cd_values, size_t namelen, char name[] )
 
[1]
H5Z_filter_t H5Pget_filter( hid_t plist_id, unsigned idx, unsigned int *flags, size_t *cd_nelmts, unsigned cd_values[], size_t namelen, char name[], unsigned *filter_config ) [2]

Purpose:
Returns information about a filter in a pipeline.

Description:
H5Pget_filter is a macro that is mapped to either H5Pget_filter1 or H5Pget_filter2, depending on the needs of the application.

Such macros are provided to facilitate application compatibility. For example:

For more information on macro use and mappings, see the “API Compatibility Macros in HDF5” document.

When both the HDF5 Library and the application are built and installed with no specific compatibility flags, H5Pget_filter is mapped to the most recent version of the function, currently H5Pget_filter2. If the library and/or application is compiled for Release 1.6 emulation, H5Pget_filter will be mapped to H5Pget_filter1. Function-specific flags are available to override these settings on a function-by-function basis when the application is compiled.

Specific compile-time compatibility flags and the resulting mappings are as follows:

Compatibility setting H5Pget_filter mapping

Global settings
No compatibility flag H5Pget_filter2 
Enable deprecated symbols H5Pget_filter2 
Disable deprecated symbols H5Pget_filter2 
Emulate Release 1.6 interface     H5Pget_filter1 

Function-level macros
H5Pget_filter_vers = 2 H5Pget_filter2
H5Pget_filter_vers = 1 H5Pget_filter1

Interface history:   Signature [1] above is the original H5Pget_filter interface and the only interface available prior to HDF5 Release 1.8.0. This signature and the corresponding function are now deprecated but will remain directly callable as H5Pget_filter1.

Signature [2] above was introduced with HDF5 Release 1.8.0 and is the recommended and default interface. It is directly callable as H5Pget_filter2.

See “API Compatibility Macros in HDF5” for circumstances under which either of these functions might not be available in an installed instance of the HDF5 Library.

Fortran90 Interface: h5pget_filter_f
SUBROUTINE h5pget_filter_f(prp_id, filter_number, flags, cd_nelmts, 
                           cd_values, namelen, name, filter_id, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id    ! Property list identifier
  INTEGER, INTENT(IN) :: filter_number    ! Sequence number within the filter
                                          ! pipeline of the filter for which
                                          ! information is sought
  INTEGER, DIMENSION(*), INTENT(OUT) :: cd_values  
                                          ! Auxiliary data for the filter
  INTEGER, INTENT(OUT) :: flags           ! Bit vector specifying certain 
                                          ! general properties of the filter
  INTEGER(SIZE_T), INTENT(INOUT) :: cd_nelmts      
                                          ! Number of elements in cd_values
  INTEGER(SIZE_T), INTENT(IN) :: namelen  ! Anticipated number of characters 
                                          ! in name
  CHARACTER(LEN=*), INTENT(OUT) :: name   ! Name of the filter
  INTEGER, INTENT(OUT) :: filter_id       ! Filter identification number
  INTEGER, INTENT(OUT) :: hdferr          ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pget_filter_f
	

History:
Release     C
1.8.0 The function H5Pget_filter renamed to H5Pget_filter1 and deprecated in this release.
The macro H5Pget_filter and the function H5Pget_filter2 introduced in this release.

Last modified: 10 June 2010
Name: H5Pget_filter1
Signature:
H5Z_filter_t H5Pget_filter1( hid_t plist_id, unsigned int idx, unsigned int *flags, size_t *cd_nelmts, unsigned int *cd_values, size_t namelen, char name[] )

Purpose:
Returns information about a filter in a pipeline.

Notice:
This function is renamed from H5Pget_filter and deprecated in favor of the function H5Pget_filter2 or the new macro H5Pget_filter.

Description:
H5Pget_filter1 returns information about a filter, specified by its filter number, in a filter pipeline, specified by the property list with which it is associated.

plist_id must be a dataset or group creation property list.

idx is a value between zero and N-1, as described in H5Pget_nfilters. The function will return a negative value if the filter number is out of range.

The structure of the flags argument is discussed in H5Pset_filter.

On input, cd_nelmts indicates the number of entries in the cd_values array, as allocated by the caller; on return,cd_nelmts contains the number of values defined by the filter.

If name is a pointer to an array of at least namelen bytes, the filter name will be copied into that array. The name will be null terminated if namelen is large enough. The filter name returned will be the name appearing in the file, the name registered for the filter, or an empty string.

Parameters:
hid_t plist_id IN: Dataset or group creation property list identifier.
int idx IN: Sequence number within the filter pipeline of the filter for which information is sought.
unsigned int *flags OUT: Bit vector specifying certain general properties of the filter.
size_t *cd_nelmts IN/OUT: Number of elements in cd_values.
unsigned int *cd_values    OUT: Auxiliary data for the filter.
size_t namelen IN: Anticipated number of characters in name.
char name[] OUT: Name of the filter.

Returns:
Returns the filter identifier if successful:
H5Z_FILTER_DEFLATE Data compression filter, employing the gzip algorithm
H5Z_FILTER_SHUFFLE Data shuffling filter
H5Z_FILTER_FLETCHER32   Error detection filter, employing the Fletcher32 checksum algorithm
H5Z_FILTER_SZIP Data compression filter, employing the SZIP algorithm
H5Z_FILTER_NBIT Data compression filter, employing the N-bit algorithm
H5Z_FILTER_SCALEOFFSET Data compression filter, employing the scale-offset algorithm
Otherwise returns a negative value.

Fortran90 Interface: h5pget_filter_f
SUBROUTINE h5pget_filter_f(prp_id, filter_number, flags, cd_nelmts, 
                           cd_values, namelen, name, filter_id, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id    ! Property list identifier
  INTEGER, INTENT(IN) :: filter_number    ! Sequence number within the filter
                                          ! pipeline of the filter for which
                                          ! information is sought
  INTEGER, DIMENSION(*), INTENT(OUT) :: cd_values  
                                          ! Auxiliary data for the filter
  INTEGER, INTENT(OUT) :: flags           ! Bit vector specifying certain 
                                          ! general properties of the filter
  INTEGER(SIZE_T), INTENT(INOUT) :: cd_nelmts      
                                          ! Number of elements in cd_values
  INTEGER(SIZE_T), INTENT(IN) :: namelen  ! Anticipated number of characters 
                                          ! in name
  CHARACTER(LEN=*), INTENT(OUT) :: name   ! Name of the filter
  INTEGER, INTENT(OUT) :: filter_id       ! Filter identification number
  INTEGER, INTENT(OUT) :: hdferr          ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pget_filter_f
	

History:

Last modified: 10 June 2010
Name: H5Pget_filter2
Signature:
H5Z_filter_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 )

Purpose:
Returns information about a filter in a pipeline.

Description:
H5Pget_filter2 returns information about a filter, specified by its filter number, in a filter pipeline, specified by the property list with which it is associated.

plist_id must be a dataset or group creation property list.

idx is a value between zero and N-1, as described in H5Pget_nfilters. The function will return a negative value if the filter number is out of range.

The structure of the flags argument is discussed in H5Pset_filter.

On input, cd_nelmts indicates the number of entries in the cd_values array, as allocated by the caller; on return,cd_nelmts contains the number of values defined by the filter.

If name is a pointer to an array of at least namelen bytes, the filter name will be copied into that array. The name will be null terminated if namelen is large enough. The filter name returned will be the name appearing in the file, the name registered for the filter, or an empty string.

filter_config is the bit field described in H5Zget_filter_info.

Parameters:
hid_t plist_id IN: Dataset or group creation property list identifier.
int idx IN: Sequence number within the filter pipeline of the filter for which information is sought.
unsigned int *flags OUT: Bit vector specifying certain general properties of the filter.
size_t *cd_nelmts IN/OUT: Number of elements in cd_values.
unsigned int *cd_values OUT: Auxiliary data for the filter.
size_t namelen IN: Anticipated number of characters in name.
char name[] OUT: Name of the filter.
unsigned int *filter_config     OUT: Bit field, as described in H5Zget_filter_info.

Returns:
Returns the filter identifier if successful:
H5Z_FILTER_DEFLATE Data compression filter, employing the gzip algorithm
H5Z_FILTER_SHUFFLE Data shuffling filter
H5Z_FILTER_FLETCHER32   Error detection filter, employing the Fletcher32 checksum algorithm
H5Z_FILTER_SZIP Data compression filter, employing the SZIP algorithm
H5Z_FILTER_NBIT Data compression filter, employing the N-bit algorithm
H5Z_FILTER_SCALEOFFSET Data compression filter, employing the scale-offset algorithm
Otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     Change
1.8.0 Function introduced in this release.
1.8.5 Function extended to work with group creation property lists.

Name: H5Pget_filter_by_id
Signatures:
herr_t H5Pget_filter_by_id( 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[] )
 
[1]
herr_t H5Pget_filter_by_id( 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 ) [2]

Purpose:
Returns information about the specified filter.

Description:
H5Pget_filter_by_id is a macro that is mapped to either H5Pget_filter_by_id1 or H5Pget_filter_by_id2, depending on the needs of the application.

Such macros are provided to facilitate application compatibility. For example:

For more information on macro use and mappings, see the “API Compatibility Macros in HDF5” document.

When both the HDF5 Library and the application are built and installed with no specific compatibility flags, H5Pget_filter_by_id is mapped to the most recent version of the function, currently H5Pget_filter_by_id2. If the library and/or application is compiled for Release 1.6 emulation, H5Pget_filter_by_id will be mapped to H5Pget_filter_by_id1. Function-specific flags are available to override these settings on a function-by-function basis when the application is compiled.

Specific compile-time compatibility flags and the resulting mappings are as follows:

Compatibility setting H5Pget_filter_by_id mapping

Global settings
No compatibility flag H5Pget_filter_by_id2 
Enable deprecated symbols H5Pget_filter_by_id2 
Disable deprecated symbols H5Pget_filter_by_id2 
Emulate Release 1.6 interface H5Pget_filter_by_id1 

Function-level macros
H5Pget_filter_by_id_vers = 2     H5Pget_filter_by_id2
H5Pget_filter_by_id_vers = 1 H5Pget_filter_by_id1

Interface history:   Signature [1] above is the original H5Pget_filter_by_id interface and the only interface available prior to HDF5 Release 1.8.0. This signature and the corresponding function are now deprecated but will remain directly callable as H5Pget_filter_by_id1.

Signature [2] above was introduced with HDF5 Release 1.8.0 and is the recommended and default interface. It is directly callable as H5Pget_filter_by_id2.

See “API Compatibility Macros in HDF5” for circumstances under which either of these functions might not be available in an installed instance of the HDF5 Library.

Fortran90 Interface: h5pget_filter_by_id_f
SUBROUTINE h5pget_filter_by_id_f(prp_id, filter_id, flags, cd_nelmts,
                                 cd_values, namelen, name, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id      ! Property list identifier
  INTEGER, INTENT(IN)        :: filter_id   ! Filter identifier
  INTEGER(SIZE_T), INTENT(INOUT)     :: cd_nelmts  
                                            ! Number of elements in cd_values
  INTEGER, DIMENSION(*), INTENT(OUT) :: cd_values  
                                            ! Auxiliary data for the filter
  INTEGER, INTENT(OUT)          :: flags    ! Bit vector specifying certain 
                                            ! general properties of the filter
  INTEGER(SIZE_T), INTENT(IN)   :: namelen  ! Anticipated number of characters 
                                            ! in name
  CHARACTER(LEN=*), INTENT(OUT) :: name     ! Name of the filter
  INTEGER, INTENT(OUT)          :: hdferr   ! Error code
                                            ! 0 on success and -1 on failure
END SUBROUTINE h5pget_filter_by_id_f
	

History:
Release     C
1.8.0 The function H5Pget_filter_by_id renamed to H5Pget_filter_by_id1 and deprecated in this release.
The macro H5Pget_filter_by_id and the function H5Pget_filter_by_id2 introduced in this release.

Last modified: 14 June 2009
Name: H5Pget_filter_by_id1
Signature:
herr_t H5Pget_filter_by_id1( 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[] )

Purpose:
Returns information about the specified filter.

Notice:
This function is renamed from H5Pget_filter_by_id and deprecated in favor of the function H5Pget_filter_by_id2 or the new macro H5Pget_filter_by_id.

Description:
H5Pget_filter_by_id1 returns information about the filter specified in filter_id, a filter identifier.

plist_id must be a dataset or group creation property list and filter_id must be in the associated filter pipeline.

The filter_id and flags parameters are used in the same manner as described in the discussion of H5Pset_filter.

Aside from the fact that they are used for output, the parameters cd_nelmts and cd_values[] are used in the same manner as described in the discussion of H5Pset_filter. On input, the cd_nelmts parameter indicates the number of entries in the cd_values[] array allocated by the calling program; on exit it contains the number of values defined by the filter.

On input, the namelen parameter indicates the number of characters allocated for the filter name by the calling program in the array name[]. On exit name[] contains the name of the filter with one character of the name in each element of the array.

If the filter specified in filter_id is not set for the property list, an error will be returned and H5Pget_filter_by_id1 will fail.

Parameters:
hid_t plist_id IN: Dataset or group creation property list identifier.
H5Z_filter_t filter_id IN: Filter identifier.
unsigned int *flags OUT: Bit vector specifying certain general properties of the filter.
size_t *cd_nelmts IN/OUT: Number of elements in cd_values.
unsigned int *cd_values OUT: Auxiliary data for the filter.
size_t namelen IN: Length of filter name and number of elements in name[].
char name[] OUT: Name of filter.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_filter_by_id_f
See the H5Pget_filter_by_id macro description.

History:

Last modified: 14 June 2010
Name: H5Pget_filter_by_id2
Signature:
herr_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 )

Purpose:
Returns information about the specified filter.

Description:
H5Pget_filter_by_id2 returns information about the filter specified in filter_id, a filter identifier.

plist_id must be a dataset or group creation property list and filter_id must be in the associated filter pipeline.

The filter_id and flags parameters are used in the same manner as described in the discussion of H5Pset_filter.

Aside from the fact that they are used for output, the parameters cd_nelmts and cd_values[] are used in the same manner as described in the discussion of H5Pset_filter. On input, the cd_nelmts parameter indicates the number of entries in the cd_values[] array allocated by the calling program; on exit it contains the number of values defined by the filter.

On input, the namelen parameter indicates the number of characters allocated for the filter name by the calling program in the array name[]. On exit name[] contains the name of the filter with one character of the name in each element of the array.

filter_config is the bit field described in H5Zget_filter_info.

If the filter specified in filter_id is not set for the property list, an error will be returned and H5Pget_filter_by_id2 will fail.

Parameters:

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_filter_by_id_f
See the H5Pget_filter_by_id macro description.

History:
Release     Change
1.8.0 Function introduced in this release.
1.8.5 Function extended to work with group creation property lists.

Name: H5Pget_gc_references
Signature:
herr_t H5Pget_gc_references(hid_t plist, unsigned *gc_ref )
Purpose:
Returns garbage collecting references setting.
Description:
H5Pget_gc_references returns the current setting for the garbage collection references property from the specified file access property list. The garbage collection references property is set by H5Pset_gc_references.
Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_gc_references_f
SUBROUTINE h5pget_gc_references_f (prp_id, gc_reference, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier
  INTEGER, INTENT(OUT) :: gc_reference ! The flag for garbage collecting
                                       ! references for the file
  INTEGER, INTENT(OUT) :: hdferr       ! Error code
                                       ! 0 on success and -1 on failure
END SUBROUTINE h5pget_gc_references_f
	

Name: H5Pget_hyper_vector_size
Signature:
herr_t H5Pget_hyper_vector_size(hid_t dxpl_id, size_t *vector_size )
Purpose:
Retrieves number of I/O vectors to be read/written in hyperslab I/O.
Description:
H5Pset_hyper_vector_size retrieves the number of I/O vectors to be accumulated in memory before being issued to the lower levels of the HDF5 library for reading or writing the actual data.

The number of I/O vectors set in the dataset transfer property list dxpl_id is returned in vector_size. Unless the default value is in use, vector_size was previously set with a call to H5Pset_hyper_vector_size.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_hyper_vector_size_f
SUBROUTINE h5pget_hyper_vector_size_f(plist_id, size, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id ! Dataset transfer property list 
                                         ! identifier
  INTEGER(SIZE_T), INTENT(OUT) :: size   ! Vector size 
  INTEGER, INTENT(OUT)       :: hdferr   ! Error code
                                         ! 0 on success and -1 on failure
END SUBROUTINE h5pget_hyper_vector_size_f
	
History:

Last modified: 7 March 2013
Name: H5Pget_istore_k
Signature:
herr_t H5Pget_istore_k( hid_t fcpl_id, unsigned * ik )

Purpose:
Queries the 1/2 rank of an indexed storage B-tree.

Description:
H5Pget_istore_k queries the 1/2 rank of an indexed storage B-tree.

The argument ik may be the null pointer (NULL).

This function is valid only for file creation property lists.

See H5Pset_istore_k for details.

Parameters:
hid_t fcpl_id     IN: File creation property list identifier
unsigned * ik OUT: Pointer to location to return the chunked storage B-tree 1/2 rank
(Default value of B-tree 1/2 rank: 32)

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_istore_k_f
SUBROUTINE h5pget_istore_k_f(prp_id, ik, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier
  INTEGER, INTENT(OUT) :: ik           ! 1/2 rank of chunked storage B-tree
  INTEGER, INTENT(OUT) :: hdferr       ! Error code
                                       ! 0 on success and -1 on failure
END SUBROUTINE h5pget_istore_k_f
    

History:
Release     C
1.6.4 ik parameter type changed to unsigned.

Name: H5Pget_layout
Signature:
H5D_layout_t H5Pget_layout(hid_t plist)
Purpose:
Returns the layout of the raw data for a dataset.
Description:
H5Pget_layout returns the layout of the raw data for a dataset. This function is only valid for dataset creation property lists.

Note that a compact storage layout may affect writing data to the dataset with parallel applications. See note in H5Dwrite documentation for details.

Parameters:
Returns:
Returns the layout type (a non-negative value) of a dataset creation property list if successful. Valid return values are:

Otherwise, returns a negative value indicating failure.

Fortran90 Interface: h5pget_layout_f
SUBROUTINE h5pget_layout_f (prp_id, layout, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier
  INTEGER, INTENT(OUT) :: layout       ! Type of storage layout for raw data
                                       ! possible values are:
                                       !    H5D_COMPACT_F
                                       !    H5D_CONTIGUOUS_F
                                       !    H5D_CHUNKED_F
  INTEGER, INTENT(OUT) :: hdferr       ! Error code
                                       ! 0 on success and -1 on failure
END SUBROUTINE h5pget_layout_f 
	

Last modified: 5 January 2011
Name: H5Pget_libver_bounds
Signature:
herr_t H5Pget_libver_bounds( hid_t fapl_id, H5F_libver_t *libver_low, H5F_libver_t *libver_high )

Purpose:
Retrieves library version bounds settings that indirectly control the format versions used when creating objects.

Description:
H5Pget_libver_bounds retrieves the lower and upper bounds on the HDF5 Library versions that indirectly determine the object formats versions used when creating objects in the file.

This property is retrieved from the file access property list specified by fapl_id.

Parameters:
hid_t fapl_id IN: File access property list identifier
H5F_libver_t *libver_low OUT: The earliest version of the library that will be used for writing objects. The library version indirectly specifies the earliest object format version that can be used when creating objects in the file.

Valid values of libver_low are as follows:
     H5F_LIBVER_EARLIEST
  H5F_LIBVER_18
  H5F_LIBVER_LATEST

H5F_libver_t *libver_high     OUT: The latest version of the library that will be used for writing objects. The library version indirectly specifies the latest object format version that can be used when creating objects in the file.

Valid values of libver_high are as follows:
     H5F_LIBVER_18
  H5F_LIBVER_LATEST

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.
1.8.6 H5F_LIBVER_18 version boundary setting added in this release.

Name: H5Pget_link_creation_order
Signature:
herr_t H5Pget_link_creation_order( hid_t gcpl_id, unsigned *crt_order_flags )

Purpose:
Queries whether link creation order is tracked and/or indexed in a group.

Description:
H5Pget_link_creation_order queries the group creation property list, gcpl_id, and returns a flag indicating whether link creation order is tracked and/or indexed in a group.

See H5Pset_link_creation_order for a list of valid creation order flags, as passed in crt_order_flags, and their meanings.

Parameters:
hid_t gcpl_id IN: Group creation property list identifier
unsigned *crt_order_flags     OUT: Creation order flag(s)
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_link_creation_order_f
SUBROUTINE h5pget_link_creation_order_f(gcpl_id, crt_order_flags, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: gcpl_id   ! Group creation property list id
  INTEGER, INTENT(OUT) :: crt_order_flags ! Creation order flag(s)
  INTEGER, INTENT(OUT) :: hdferr          ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pget_link_creation_order_f  
    

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_link_phase_change
Signature:
herr_t H5Pget_link_phase_change( hid_t gcpl_id, unsigned *max_compact, unsigned *min_dense )

Purpose:
Queries the settings for conversion between compact and dense groups.

Description:
H5Pget_link_phase_change queries the maximum number of entries for a compact group and the minimum number links to require before converting a group to a dense form.

In the compact format, links are stored as messages in the group’s header. In the dense format, links are stored in a fractal heap and indexed with a version 2 B-tree.

max_compact is the maximum number of links to store as header messages in the group header before converting the group to the dense format. Groups that are in the compact format and exceed this number of links are automatically converted to the dense format.

min_dense is the minimum number of links to store in the dense format. Groups which are in dense format and in which the number of links falls below this number are automatically converted back to the compact format.

In the compact format, links are stored as messages in the group’s header. In the dense format, links are stored in a fractal heap and indexed with a version 2 B-tree.

See H5Pset_link_phase_change for a discussion of traditional, compact, and dense group storage.

Parameters:
hid_t gcpl_id IN: Group creation property list identifier
unsigned *max_compact     OUT: Maximum number of links for compact storage
unsigned *min_dense OUT: Minimum number of links for dense storage
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
SUBROUTINE h5pset_link_phase_change_f(gcpl_id, max_compact, min_dense, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: gcpl_id 
                                  ! Group creation property list identifier
  INTEGER, INTENT(IN) :: max_compact  
                                  ! Maximum number of attributes to be stored 
                                  ! in compact storage
  INTEGER, INTENT(IN) :: min_dense  
                                  ! Minimum number of attributes to be stored 
                                  ! in dense storage
  INTEGER, INTENT(OUT) :: hdferr  ! Error code
                                  ! 0 on success and -1 on failure
END SUBROUTINE h5pset_link_phase_change_f 
    

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_local_heap_size_hint
Signature:
herr_t H5Pget_local_heap_size_hint( hid_t gcpl_id, size_t *size_hint )

Purpose:
Retrieves the anticipated size of the local heap for original-style groups.

Description:
H5Pget_local_heap_size_hint queries the group creation property list, gcpl_id, for the anticipated size of the local heap, size_hint, for original-style groups, i.e., for groups of the style used prior to HDF5 Release 1.8.0.

See H5Pset_local_heap_size_hint for further discussion.

Parameters:
hid_t gcpl_id IN: Group creation property list identifier
size_t *size_hint     OUT: Anticipated size of local heap

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
SUBROUTINE h5pget_local_heap_size_hint_f(gcpl_id, size_hint, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: gcpl_id 
                                  ! Group creation property list identifier
  INTEGER(SIZE_T), INTENT(OUT) :: size_hint 
                                  ! Hint for size of local heap
  INTEGER, INTENT(OUT) :: hdferr  ! Error code
                                  ! 0 on success and -1 on failure
END SUBROUTINE h5pget_local_heap_size_hint_f
    

History:
Release     Change
1.8.0 Function introduced in this release.

Last modified: 21 March 2012
Name: H5Pget_mcdt_search_cb
Signature:
herr_t H5Pget_mcdt_search_cb( hid_t ocpypl_id, H5O_mcdt_search_cb_t *func, void **op_data )

Purpose:
Retrieves the callback function from the specified object copy property list.

Description:
H5Pget_mcdt_search_cb retrieves the user-defined callback function and the user data that are set via H5Pset_mcdt_search_cb in the object copy property list ocpypl_id.

The callback function will be returned in the parameter func and the user data will be returned in the parameter op_data.

Parameters:
hid_t ocpypl_id      IN: Object copy property list identifier
H5O_mcdt_search_cb_t *func   OUT: User-defined callback function
void **op_data   OUT: User-defined input data for the callback function

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Failure Modes:
H5Pget_mcdt_search_cb will fail if the object copy property list is invalid.

See Also:
H5Ocopy
H5Pset_copy_object
  H5Pset_mcdt_search_cb
H5O_mcdt_search_cb_t

Copying Committed Datatypes
    with H5Ocopy
 
A comprehensive discussion of copying committed datatypes (PDF) in Advanced Topics in HDF5

History:
Release     Change
1.8.9 C function introduced in this release.

Name: H5Pget_mdc_config
Signature:
herr_t H5Pget_mdc_config(hid_t plist_id, H5AC_cache_config_t *config_ptr)
Purpose:
Get the current initial metadata cache configuration from the indicated File Access Property List.
Description:
H5Pget_mdc_config gets the initial metadata cache configuration contained in a file access property list and loads it into the instance of H5AC_cache_config_t pointed to by the config_ptr parameter. This configuration is used when the file is opened.

Note that the version field of *config_ptr must be initialized; this allows the library to support old versions of the H5AC_cache_config_t structure.

See the overview of the metadata cache in the special topics section of the user guide for details on the configuration data returned. If you haven't read and understood that documentation, the results of this call will not make much sense.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Name: H5Pget_meta_block_size
Signature:
herr_t H5Pget_meta_block_size( hid_t fapl_id, hsize_t *size )
Purpose:
Returns the current metadata block size setting.
Description:
H5Pget_meta_block_size returns the current minimum size, in bytes, of new metadata block allocations. This setting is retrieved from the file access property list fapl_id.

This value is set by H5Pset_meta_block_size and is retrieved from the file access property list fapl_id.

Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Fortran90 Interface: h5pget_meta_block_size_f
SUBROUTINE h5pget_meta_block_size_f(plist_id, size, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id ! File access property list 
                                         ! identifier
  INTEGER(HSIZE_T), INTENT(OUT) :: size  ! Metadata block size
  INTEGER, INTENT(OUT)       :: hdferr   ! Error code
                                         ! 0 on success and -1 on failure
END SUBROUTINE h5pget_meta_block_size_f
	
History:

Last modified: 24 September 2012
Name: H5Pget_mpio_actual_chunk_opt_mode
Signature:
herr_t H5Pget_mpio_actual_chunk_opt_mode( hid_t dxpl_id, H5D_mpio_actual_chunk_opt_mode_t * actual_chunk_opt_mode)

Purpose: Retrieves the type of chunk optimization that HDF5 actually performed on the last parallel I/O call. This is not necessarily the type of optimization requested.

Motivation:
A user can request collective I/O via a data transfer property list (DXPL) that has been suitably modified with H5Pset_dxpl_mpio. The operation can be optimized in several different ways, some of which also can be requested by the user. However, HDF5 may not be able to satisfy requests for specific optimizations and may choose a different optimization scheme. This property allows the user to track which optimization was actually used. Used in conjunction with H5Pget_mpio_actual_io_mode, this property allows the user to determine exactly what HDF5 did when attempting collective chunked I/O.

Description:
H5Pget_mpio_actual_chunk_opt_mode retrieves the type of chunk optimization performed when collective I/O was requested. This property is set before I/O takes place, and will be set even if I/O fails.

Valid values returned in actual_chunk_opt_mode:
  H5D_MPIO_NO_CHUNK_OPTIMIZATION   No chunk optimization was performed. Either no collective I/O was attempted or the dataset wasn't chunked.
(Default)
  H5D_MPIO_MULTI_CHUNK   Each chunk was individually assigned collective or independent I/O based on what fraction of processes access the chunk. If the fraction is greater than the multi chunk ratio threshold, collective I/O is performed on that chunk. The multi chunk ratio threshold can be set using H5Pset_dxpl_mpio_chunk_opt_ratio. The default value is 60%.
  H5D_MPIO_MULTI_CHUNK_NO_OPT   Each chunk is assigned collective or independent I/O based on how many chunks were accessed before it. Collective I/O is performed on the the first chunk in each selection, then the second, and so on until one process finishes, then the remaining processes perform independent I/O on the rest of their selections.
  H5D_MPIO_LINK_CHUNK   Collective I/O is performed on all chunks simultaneously.

Parameters:
hid_t dxpl_id      IN: Dataset transfer property list identifier
H5D_mpio_actual_chunk_opt_mode_t * actual_chunk_opt_mode   OUT: The type of chunk optimization performed by HDF5.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

See Also:
H5Pget_mpio_no_collective_cause   Reports whether collective I/O was performed on a particular call and, if not, the causes that broke collective I/O.
H5Pget_mpio_actual_io_mode Reports type of I/O HDF5 actually performed.
 
The following functions request optimizations or change values that HDF5 uses to choose an optimization scheme:
H5Pset_dxpl_mpio_chunk_opt
H5Pset_dxpl_mpio_chunk_opt_num
H5Pset_dxpl_mpio_chunk_opt_ratio
H5Pset_dxpl_mpio_collective_opt

History:
Release     Change
1.8.8 C function introduced in this release.

Last modified: 15 October 2012
Name: H5Pget_mpio_actual_io_mode
Signature:
herr_t H5Pget_mpio_actual_io_mode( hid_t dxpl_id, H5D_mpio_actual_io_mode_t * actual_io_mode)

Purpose: Retrieves the type of I/O that HDF5 actually performed on the last parallel I/O call. This is not necessarily the type of I/O requested.

Motivation:
A user can request collective I/O via a data transfer property list (DXPL) that has been suitably modified with H5Pset_dxpl_mpio. However, HDF5 will sometimes ignore this request and perform independent I/O instead. This property allows the user to see what kind of I/O HDF5 actually performed. Used in conjunction with H5Pget_mpio_actual_chunk_opt_mode, this property allows the user to determine exactly HDF5 did when attempting collective I/O.

Description:
H5Pget_mpio_actual_io_mode retrieves the type of I/O performed on the selection of the current process. This property is set after all I/O is completed; if I/O fails, it will not be set.

Valid values returned in actual_io_mode:
  H5D_MPIO_NO_COLLECTIVE   No collective I/O was performed. Collective I/O was not requested or collective I/O isn't possible on this dataset.
(Default)
  H5D_MPIO_CHUNK_INDEPENDENT   HDF5 performed one the chunk collective optimization schemes and each chunk was accessed independently.
  H5D_MPIO_CHUNK_COLLECTIVE   HDF5 performed one the chunk collective optimization schemes and each chunk was accessed collectively.
  H5D_MPIO_CHUNK_MIXED   HDF5 performed one the chunk collective optimization schemes and some chunks were accessed independently, some collectively.
  H5D_MPIO_CONTIGUOUS_COLLECTIVE   Collective I/O was performed on a contiguous dataset.

Note:
All processes do not need to have the same value. For example, if I/O is being performed using the multi chunk optimization scheme, one process's selection may include only chunks accessed collectively, while another may include chunks accessed independently. In this case, the first process will report H5D_MPIO_CHUNK_COLLECTIVE while the second will report H5D_MPIO_CHUNK_INDEPENDENT.

Parameters:
hid_t dxpl_id      IN: Dataset transfer property list identifier
H5D_mpio_actual_io_mode_t * actual_io_mode   OUT: The type of I/O performed by this process.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

See Also:
H5Pget_mpio_no_collective_cause Reports whether collective I/O was performed on a particular call and, if not, the causes that broke collective I/O.
H5Pget_mpio_actual_chunk_opt_mode   Reports type of optimization HDF5 actually attempted.

Fortran90 Interface: h5pget_mpio_actual_io_mode_f

Signature:

  SUBROUTINE h5pget_mpio_actual_io_mode_f(dxpl_id,       &
        actual_io_mode, hdferr)
    IMPLICIT NONE
    INTEGER(HID_T), INTENT(IN)  :: dxpl_id
    INTEGER       , INTENT(OUT) :: actual_io_mode
    INTEGER       , INTENT(OUT) :: hdferr

Inputs:

  dxpl_id        - Dataset transfer property list identifier.

Outputs:

  actual_io_mode - The type of I/O performed by this process.
  hdferr         - Returns 0 if successful and -1 if fails.

History:
Release     Change
1.8.10 Fortran subroutine introduced in this release.
1.8.8 C function introduced in this release.

Last modified: 24 September 2012
Name: H5Pget_mpio_no_collective_cause
Signature:
herr_t H5Pget_mpio_no_collective_cause( hid_t dxpl_id, uint32_t * local_no_collective_cause, uint32_t * global_no_collective_cause)

Purpose:
Retrieves local and global causes that broke collective I/O on the last parallel I/O call.

Motivation:
A user can request collective I/O via a data transfer property list (DXPL) that has been suitably modified with H5Pset_dxpl_mpio. However, there are conditions that can cause HDF5 to forgo collective I/O and perform independent I/O. Such causes can be different across the processes of a parallel application. This function allows the user to determine what caused the HDF5 Library to skip collective I/O locally, that is in the local process, and globally, across all processes.

Description:
H5Pget_mpio_no_collective_cause serves two purposes. It can be used to determine whether collective I/O was used for the last preceding parallel I/O call. If collective I/O was not used, the function retrieves the local and global causes that broke collective I/O on that parallel I/O call. The properties retrieved by this function are set before I/O takes place and are retained even when I/O fails.

Valid values returned in local_no_collective_cause and global_no_collective_cause are as follows or, if there are multiple causes, a bitwise OR of the relevant causes; the numbers in the center column are the bitmask values:
  H5D_MPIO_COLLECTIVE 00000000   Collective I/O was performed successfully.
(Default)
  H5D_MPIO_SET_INDEPENDENT 00000001   Collective I/O was not performed because independent I/O was requested.
  H5D_MPIO_DATATYPE_CONVERSION     00000010   Collective I/O was not performed because datatype conversions were required.
  H5D_MPIO_DATA_TRANSFORMS 00000100   Collective I/O was not performed because data transforms needed to be applied.
  H5D_MPIO_SET_MPIPOSIX 00001000   Collective I/O was not performed because the selected file driver was MPI-POSIX.
  H5D_MPIO_NOT_SIMPLE_OR_SCALAR_DATASPACES
    00010000   Collective I/O was not performed because one of the dataspaces was neither simple nor scalar.
  H5D_MPIO_POINT_SELECTIONS 00100000   Collective I/O was not performed because there were point selections in one of the dataspaces.
  H5D_MPIO_NOT_CONTIGUOUS_OR_CHUNKED_DATASET
    01000000   Collective I/O was not performed because the dataset was neither contiguous nor chunked.
  H5D_MPIO_FILTERS 10000000   Collective I/O was not performed because filters needed to be applied.

The above name/value pairs are members of HDF5’s H5D_mpio_no_collective_cause_t enumeration.

Note:
Each process determines whether it can perform collective I/O and broadcasts the result. Those results are combined to make a collective decision; collective I/O will be performed only if all processes can perform collective I/O.

If collective I/O was not used, the causes that prevented it are reported by individual process by means of an enumerated set. The causes may differ among processes, so H5Pget_mpio_no_collective_cause returns two property values. The first value is the one produced by the local process to report local causes. This local information is encoded in an enumeration, the H5D_mpio_no_collective_cause_t described above, with all individual causes combined into a single enumeration value by means of a bitwise OR operation. The second value reports global causes; this global value is the result of a bitwise-OR operation across the values returned by all the processes.

Parameters:
hid_t dxpl_id      IN: Dataset transfer property list identifier
uint32_t *local_no_collective_cause   OUT: An enumerated set value indicating the causes that prevented collective I/O in the local process.
uint32_t *global_no_collective_cause   OUT: An enumerated set value indicating the causes across all processes that prevented collective I/O.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

See Also:
H5Pget_mpio_actual_chunk_opt_mode   Reports type of optimization HDF5 actually attempted.
H5Pget_mpio_actual_io_mode Reports type of I/O HDF5 actually performed.

History:
Release     Change
1.8.10 C function introduced in this release.

Name: H5Pget_multi_type
Signature:
herr_t H5Pget_multi_type ( hid_t fapl_id, H5FD_mem_t *type )
Purpose:
Retrieves type of data property for MULTI driver.
Description:
H5Pget_multi_type retrieves the type of data setting from the file access or data transfer property list fapl_id. This enables a user application to specify the type of data the application wishes to access so that the application can retrieve a file handle for low-level access to the particular member of a set of MULTI files in which that type of data is stored. The file handle is retrieved with a separate call to H5Fget_vfd_handle (or, in special circumstances, to H5FDget_vfd_handle; see Virtual File Layer and List of VFL Functions in HDF5 Technical Notes).

The type of data returned in type will be one of those listed in the discussion of the type parameter in the the description of the function H5Pset_multi_type.

Use of this function is only appropriate for an HDF5 file written as a set of files with the MULTI file driver.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface:
None.
History:

Name: H5Pget_nfilters
Signature:
int H5Pget_nfilters(hid_t plist)
Purpose:
Returns the number of filters in the pipeline.
Description:
H5Pget_nfilters returns the number of filters defined in the filter pipeline associated with the property list plist.

In each pipeline, the filters are numbered from 0 through N-1, where N is the value returned by this function. During output to the file, the filters are applied in increasing order; during input from the file, they are applied in decreasing order.

H5Pget_nfilters returns the number of filters in the pipeline, including zero (0) if there are none.

Note:
This function currently supports only the permanent filter pipeline; plist_id must be a dataset creation property list.
Parameters:
Returns:
Returns the number of filters in the pipeline if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_nfilters_f
SUBROUTINE h5pget_nfilters_f(prp_id, nfilters, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id   ! Dataset creation property 
                                         ! list identifier 
  INTEGER, INTENT(OUT) :: nfilters       ! The number of filters in 
                                         ! the pipeline
  INTEGER, INTENT(OUT)       :: hdferr   ! Error code
                                         ! 0 on success and -1 on failure
END SUBROUTINE h5pget_nfilters_f
	

Name: H5Pget_nlinks
Signature:
herr_t H5Pget_nlinks( hid_t lapl_id, size_t *nlinks )

Purpose:
Retrieves the maximum number of link traversals.

Description:
H5Pget_nlinks retrieves the maximum number of soft or user-defined link traversals allowed, nlinks, before the library assumes it has found a cycle and aborts the traversal. This value is retrieved from the link access property list lapl_id.

The limit on the number soft or user-defined link traversals is designed to terminate link traversal if one or more links form a cycle. User control is provided because some files may have legitimate paths formed of large numbers of soft or user-defined links. This property can be used to allow traversal of as many links as desired.

Parameters:
hid_t fapl_id IN: File access property list identifier
size_t *nlinks     OUT: Maximum number of links to traverse

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_nlinks_f
SUBROUTINE h5pget_nlinks_f(lapl_id, nlinks, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: lapl_id 
                                     ! File access property list identifier
  INTEGER(SIZE_T), INTENT(OUT) :: nlinks 
                                     ! Maximum number of links to traverse
  INTEGER, INTENT(OUT) :: hdferr     ! Error code
                                     ! 0 on success and -1 on failure
END SUBROUTINE h5pget_nlinks_f
    

History:
Release     C
1.8.0 Function introduced in this release.

Last modified: 28 March 2014
Name: H5Pget_nprops
Signature:
herr_t H5Pget_nprops( hid_t plist_id, size_t *nprops )

Purpose:
Queries the number of properties in a property list or class.

Description:
H5Pget_nprops retrieves the number of properties in a property list or property list class.

If plist_id is a property list identifier, the current number of properties in the list is returned in nprops.

If plist_id is a property list class identifier, the number of registered properties in the class is returned in nprops.

Parameters:
hid_t plist_id IN: Identifier for property object to query
size_t *nprops     OUT: Number of properties in object

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_nprops_f
SUBROUTINE h5pget_nprops_f(prp_id, nprops, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id    ! Property list identifier 
  INTEGER(SIZE_T), INTENT(OUT) :: nprops  ! Number of properties
  INTEGER, INTENT(OUT) :: hdferr          ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pget_nprops_f
	

Name: H5Pget_preserve
Signature:
int H5Pget_preserve(hid_t plist)
Purpose:
Checks status of the dataset transfer property list.

Notice:
This function is deprecated as it is no longer useful; compound datatype field preservation is now core functionality in the HDF5 Library.

Description:
H5Pget_preserve checks the status of the dataset transfer property list.
Parameters:
Returns:
Returns TRUE or FALSE if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_preserve_f
SUBROUTINE h5pget_preserve_f(prp_id, flag, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id   ! Dataset transfer property 
                                         ! list identifier 
  LOGICAL, INTENT(OUT)       :: flag     ! Status of for the dataset 
                                         ! transfer property list 
  INTEGER, INTENT(OUT)       :: hdferr   ! Error code
                                         ! 0 on success and -1 on failure
END SUBROUTINE h5pget_preserve_f
	
History:

Name: H5Pget_obj_track_times
Signature:
herr_t H5Pget_obj_track_times( hid_t ocpl_id, hbool_t *track_times )

Purpose:
Determines whether times associated with an object are being recorded.

Description:
H5get_obj_track_times queries the object creation property list, ocpl_id, to determine whether object times are being recorded.

If track_times is returned as TRUE, times are being recorded; if track_times is returned as FALSE, times are not being recorded.

Time data can be retrieved with H5Oget_info, which will return it in the H5O_info_t struct.

If times are not tracked, they will be reported as follows when queried:
    12:00 AM UDT, Jan. 1, 1970

See H5Pset_obj_track_times for further discussion.

Parameters:

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_obj_track_times_f
SUBROUTINE h5pget_obj_track_times_f(plist_id, flag, hdferr)
    IMPLICIT NONE
    INTEGER(HID_T), INTENT(IN) :: plist_id 
                                   ! Dataset creation property 
                                   ! list identifier 
    LOGICAL, INTENT(OUT) :: flag   ! Object timestamp setting
    INTEGER, INTENT(OUT) :: hdferr ! Error code
                                   ! 0 on success and -1 on failure
END SUBROUTINE h5pget_obj_track_times_f
    

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_shared_mesg_index
Signature:
herr_t H5Pget_shared_mesg_index( hid_t fcpl_id, unsigned index_num, unsigned *mesg_type_flags, unsigned *min_mesg_size )

Purpose:
Retrieves the configuration settings for a shared message index.

Description:
H5Pget_shared_mesg_index retrieves the message type and minimum message size settings from the file creation property list fcpl_id for the shared object header message index specified by index_num.

index_num specifies the index. index_num is zero-indexed, so in a file with three indexes, they will be numbered 0, 1, and 2.

mesg_type_flags and min_mesg_size will contain, respectively, the types of messages and the minimum size, in bytes, of messages that can be stored in this index.

Valid message types are described in H5Pset_shared_mesg_index.

Parameters:
hid_t fcpl_id IN: File creation property list identifier.
unsigned index_num IN: Index being configured.
unsigned *mesg_type_flags     OUT: Types of messages that may be stored in this index.
unsigned *min_mesg_size OUT: Minimum message size.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_shared_mesg_nindexes
Signature:
herr_t H5Pget_shared_mesg_nindexes( hid_t fcpl_id, unsigned *nindexes )

Purpose:
Retrieves number of shared object header message indexes in file creation property list.

Description:
H5Pget_shared_mesg_nindexes retrieves the number of shared object header message indexes in the specified file creation property list fcpl_id.

If the value of nindexes is 0 (zero), shared object header messages are disabled in files created with this property list.

Parameters:
hid_t fcpl_id IN: File creation property list
unsigned *nindexes     OUT: Number of shared object header message indexes available in files created with this property list

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.

Last modified: 11 March 2013
Name: H5Pget_shared_mesg_phase_change
Signature:
herr_t H5Pget_shared_mesg_phase_change( hid_t fcpl_id, unsigned *max_list, unsigned *min_btree )

Purpose:
Retrieves shared object header message phase change information.

Description:
H5Pget_shared_mesg_phase_change retrieves the threshold values for storage of shared object header message indexes in a file. These phase change thresholds determine the point at which the index storage mechanism changes from a more compact list format to a more performance-oriented B-tree format, and vice-versa.

By default, a shared object header message index is initially stored as a compact list. When the number of messages in an index exceeds the specified max_list threshold, storage switches to a B-tree format for improved performance. If the number of messages subsequently falls below the min_btree threshold, the index will revert to the list format.

If max_list is set to 0 (zero), shared object header message indexes in the file will always be stored as B-trees.

fcpl_id specifies the file creation property list.

Parameters:
hid_t fcpl_id IN: File creation property list identifier
unsigned *max_list    OUT: Threshold above which storage of a shared object header message index shifts from list to B-tree
unsigned *min_btree     OUT: Threshold below which storage of a shared object header message index reverts to list format

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pget_sieve_buf_size
Last modified: 14 April 2010
Signature:
herr_t H5Pget_sieve_buf_size( hid_t fapl_id, size_t *size )

Purpose:
Returns maximum data sieve buffer size.

Description:
H5Pget_sieve_buf_size retrieves, size, the current maximum size of the data sieve buffer.

This value is set by H5Pset_sieve_buf_size and is retrieved from the file access property list fapl_id.

Parameters:
hid_t fapl_id     IN: File access property list identifier.
size_t *size IN: Maximum size, in bytes, of data sieve buffer.

Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Fortran90 Interface: h5pget_sieve_buf_size_f
SUBROUTINE h5pget_sieve_buf_size_f(plist_id, size, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id ! File access property list 
                                         ! identifier
  INTEGER(SIZE_T), INTENT(OUT) :: size   ! Sieve buffer size 
  INTEGER, INTENT(OUT)       :: hdferr   ! Error code
                                         ! 0 on success and -1 on failure
END SUBROUTINE h5pget_sieve_buf_size_f 

History:
Release     C
1.6.0 The size parameter has changed from type hsize_t to size_t.
1.4.0 Function introduced in this release.

Name: H5Pget_size
Signature:
int H5Pget_size( hid_t id, const char *name, size_t *size )
Purpose:
Queries the size of a property value in bytes.
Description:
H5Pget_size retrieves the size of a property's value in bytes. This function operates on both property lists and property classes

Zero-sized properties are allowed and return 0.

Parameters:
Returns:
Success: a non-negative value
Failure: a negative value
Fortran90 Interface: h5pget_size_f
SUBROUTINE h5pget_size_f(prp_id, name, size, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier 
  CHARACTER(LEN=*), INTENT(IN) :: name  ! Name of property to query
  INTEGER(SIZE_T), INTENT(OUT) :: size  ! Size in bytes
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pget_size_f
	

Name: H5Pget_sizes
Signature:
herr_t H5Pget_sizes(hid_t plist, size_t * sizeof_addr, size_t * sizeof_size )
Purpose:
Retrieves the size of the offsets and lengths used in an HDF5 file.
Description:
H5Pget_sizes retrieves the size of the offsets and lengths used in an HDF5 file. This function is only valid for file creation property lists.
Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_sizes_f
SUBROUTINE h5pget_sizes_f(prp_id, sizeof_addr, sizeof_size, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier
  INTEGER(SIZE_T), DIMENSION(:), INTENT(OUT) :: sizeof_addr
                                        ! Size of an object address in bytes
  INTEGER(SIZE_T), DIMENSION(:), INTENT(OUT) :: sizeof_size 
                                        ! Size of an object in bytes
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pget_sizes_f
	

Name: H5Pget_small_data_block_size
Signature:
herr_t H5Pget_small_data_block_size(hid_t fapl_id, hsize_t *size )
Purpose:
Retrieves the current small data block size setting.
Description:
H5Pget_small_data_block_size retrieves the current setting for the size of the small data block.

If the returned value is zero (0), the small data block mechanism has been disabled for the file.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise a negative value.
Fortran90 Interface: h5pget_small_data_block_size_f
SUBROUTINE h5pget_small_data_block_size_f(plist_id, size, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id  ! File access property list 
                                          ! identifier
  INTEGER(HSIZE_T), INTENT(OUT) :: size   ! Small raw data block size
  INTEGER, INTENT(OUT)       :: hdferr    ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pget_small_data_block_size_f
	
History:

Last modified: 7 March 2013
Name: H5Pget_sym_k
Signature:
herr_t H5Pget_sym_k( hid_t fcpl_id, unsigned * ik, unsigned * lk )

Purpose:
Retrieves the size of the symbol table B-tree 1/2 rank and the symbol table leaf node 1/2 size.

Description:
H5Pget_sym_k retrieves the size of the symbol table B-tree 1/2 rank and the symbol table leaf node 1/2 size.

This function is valid only for file creation property lists.

If a parameter value is set to NULL, that parameter is not retrieved.

See the H5Pset_sym_k function description for more information.

Parameters:
hid_t fcpl_id     IN: File creation property list identifier
unsigned * ik OUT: Pointer to location to return the symbol table's B-tree 1/2 rank
(Default value of B-tree 1/2 rank: 16)
unsigned * lk OUT: Pointer to location to return the symbol table's leaf node 1/2 size
(Default value of leaf node 1/2 size: 4)

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pget_sym_k_f
SUBROUTINE h5pget_sym_k_f(prp_id, ik, lk, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier
  INTEGER, INTENT(OUT) :: ik            ! Symbol table tree rank
  INTEGER, INTENT(OUT) :: lk            ! Symbol table node size
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pget_sym_k_f
    

History:
Release     C
1.6.4 ik parameter type changed to unsigned
1.6.0 The ik parameter has changed from type int to unsigned

Name: H5Pget_type_conv_cb
Signature:
herr_t H5Pget_type_conv_cb(hid_t plist, H5T_conv_except_func_t *func, void **op_data)
Purpose:
Gets user-defined datatype conversion callback function.
Description:
H5Pget_type_conv_cb gets the user-defined datatype conversion callback function func in the dataset transfer property list plist.

The parameter op_data is a pointer to user-defined input data for the callback function.

The callback function func defines the actions an application is to take when there is an exception during datatype conversion.

Please refer to the function H5Pset_type_conv_cb for more details.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface:
None.

Name: H5Pget_userblock
Signature:
herr_t H5Pget_userblock(hid_t plist, hsize_t * size )
Purpose:
Retrieves the size of a user block.
Description:
H5Pget_userblock retrieves the size of a user block in a file creation property list.
Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_userblock_f
SUBROUTINE h5pget_userblock_f(prp_id, block_size, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id   ! Property list identifier
  INTEGER(HSIZE_T), DIMENSION(:), INTENT(OUT) ::  block_size 
                                         ! Size of the user-block in bytes
  INTEGER, INTENT(OUT) :: hdferr         ! Error code
                                         ! 0 on success and -1 on failure
END SUBROUTINE h5pget_userblock_f
	

Name: H5Pget_version
Signature:
herr_t H5Pget_version(hid_t plist, unsigned * super, unsigned * freelist, unsigned * stab, unsigned * shhdr )
Purpose:
Retrieves the version information of various objects for a file creation property list.
Description:
H5Pget_version retrieves the version information of various objects for a file creation property list. Any pointer parameters which are passed as NULL are not queried.
Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pget_version_f
SUBROUTINE h5pget_version_f(prp_id, boot, freelist, & 
                            stab, shhdr, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id         ! Property list identifier
  INTEGER, DIMENSION(:), INTENT(OUT) :: boot   ! Array to put boot block 
                                               ! version number
  INTEGER, DIMENSION(:), INTENT(OUT) :: freelist  
                                               ! Array to put global
                                               ! freelist version number
  INTEGER, DIMENSION(:), INTENT(OUT) :: stab   ! Array to put symbol table
                                               ! version number
  INTEGER, DIMENSION(:), INTENT(OUT) :: shhdr  ! Array to put shared object 
                                               ! header version number
  INTEGER, INTENT(OUT) :: hdferr               ! Error code
                                               ! 0 on success and -1 on failure
END SUBROUTINE h5pget_version_f
	
History:

Last modified: 8 April 2014

Name: H5Pget_vlen_mem_manager

Signature:
herr_t H5Pget_vlen_mem_manager(hid_t plist, H5MM_allocate_t *alloc, void **alloc_info, H5MM_free_t *free, void **free_info)

Purpose:
Gets the memory manager for variable-length datatype allocation in H5Dread and H5Dvlen_reclaim.

Description:
H5Pget_vlen_mem_manager is the companion function to H5Pset_vlen_mem_manager, returning the parameters set by that function.

Parameters:
hid_t plist IN: Identifier for the dataset transfer property list.
H5MM_allocate_t *alloc OUT: User’s allocate routine, or NULL for system malloc.
void **alloc_info OUT: Extra parameter for user’s allocation routine. Contents are ignored if preceding parameter is NULL.
H5MM_free_t *free OUT: User’s free routine, or NULL for system free.
void **free_info OUT: Extra parameter for user’s free routine. Contents are ignored if preceding parameter is NULL.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
None.





Last modified: 23 August 2012
Name: H5Pinsert
Signatures:
herr_t H5Pinsert( 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_close_func_t close )
 
[1]
herr_t H5Pinsert( 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 ) [2]
Purpose:
Registers a temporary property with a property list.

Description:
H5Pinsert is a macro that is mapped to either H5Pinsert1 or H5Pinsert2, depending on the needs of the application.

Such macros are provided to facilitate application compatibility. For example:

When both the HDF5 Library and the application are built and installed with no specific compatibility flags, H5Pinsert is mapped to the most recent version of the function, currently H5Pinsert2. If the library and/or application is compiled for Release 1.6 emulation, H5Pinsert will be mapped to H5Pinsert1. Function-specific flags are available to override these settings on a function-by-function basis when the application is compiled.

Specific compile-time compatibility flags and the resulting mappings are as follows:

Compatibility setting H5Pinsert mapping

Global settings
No compatibility flag H5Pinsert2 
Enable deprecated symbols H5Pinsert2 
Disable deprecated symbols H5Pinsert2 
Emulate Release 1.6 interface H5Pinsert1 

Function-level macros
H5Pinsert_vers = 2     H5Pinsert2
H5Pinsert_vers = 1 H5Pinsert1

For more information on macro use and mappings, see the “API Compatibility Macros in HDF5” document.

Interface history:   Signature [1] above is the original H5Pinsert interface and the only interface available prior to HDF5 Release 1.8.0. This signature and the corresponding function are now deprecated but will remain directly callable as H5Pinsert1.

Signature [2] above was introduced with HDF5 Release 1.8.0 and is the recommended and default interface. It is directly callable as H5Pinsert2.

See “API Compatibility Macros in HDF5” for circumstances under which either of these functions might not be available in an installed instance of the HDF5 Library.

Programming Note for C++ Developers Using C Functions:

If a C routine that takes a function pointer as an argument is called from within C++ code, the C routine should be returned from normally.

Examples of this kind of routine include callbacks such as H5Pset_elink_cb and H5Pset_type_conv_cb and functions such as H5Tconvert and H5Ewalk2.

Exiting the routine in its normal fashion allows the HDF5 C Library to clean up its work properly. In other words, if the C++ application jumps out of the routine back to the C++ “catch” statement, the library is not given the opportunity to close any temporary data structures that were set up when the routine was called. The C++ application should save some state as the routine is started so that any problem that occurs might be diagnosed.

Fortran90 Interface: h5pinsert_f
Signature:

  SUBROUTINE h5pinsert_f
    INTEGER(HID_T)  , INTENT(IN)  :: plist
    CHARACTER(LEN=*), INTENT(IN)  :: name
    INTEGER(SIZE_T) , INTENT(IN)  :: size
    TYPE            , INTENT(IN)  :: value
    INTEGER         , INTENT(OUT) :: hdferr

Inputs:

  plist  - Property list class identifier
  name   - Name of property to insert
  size   - Size of the property value
  value  - Property value, supported types are:
             INTEGER
             REAL
             DOUBLE PRECISION
             CHARACTER(LEN=*)

Outputs:

  hdferr - Returns 0 if successful and -1 if fails

Fortran2003 Interface: h5pinsert_f
Signature:

  SUBROUTINE h5pinsert_f
    INTEGER(HID_T)  , INTENT(IN)  :: plist
    CHARACTER(LEN=*), INTENT(IN)  :: name
    INTEGER(SIZE_T) , INTENT(IN)  :: size
    TYPE(C_PTR)     , INTENT(IN)  :: value
    INTEGER         , INTENT(OUT) :: hdferr

Inputs:

  plist  - Property list class identifier
  name   - Name of property to insert
  size   - Size of the property value
  value  - Pointer to new value pointer for the property being modified

Outputs:

  hdferr - Returns 0 if successful and -1 if fails

History:
Release     Change
1.8.8 Fortran updated to Fortran2003.
1.8.0 The function C function H5Pinsert renamed to H5Pinsert1 and deprecated in this release.
C macro H5Pinsert and the C function H5Pinsert2 introduced in this release.

Last modified: 23 August 2012
Name: H5Pinsert1
Signature:
herr_t H5Pinsert1( 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_close_func_t close )

Purpose:
Registers a temporary property with a property list.

Notice:
This function is renamed from H5Pinsert and deprecated in favor of the function H5Pinsert2 or the new macro H5Pinsert.

Description:
H5Pinsert1 create a new property in a property list. The property will exist only in this property list and copies made from it.

The initial property value must be provided in value and the property value will be set accordingly.

The name of the property must not already exist in this list, or this routine will fail.

The set and get callback routines may be set to NULL if they are not needed.

Zero-sized properties are allowed and do not store any data in the property list. The default value of a zero-size property may be set to NULL. They may be used to indicate the presence or absence of a particular piece of information.

The set routine is called before a new value is copied into the property. The H5P_prp_set_func_t callback function is defined as follows: The parameters to the callback function are defined as follows: The set routine may modify the value pointer to be set and those changes will be used when setting the property's value. If the set routine returns a negative value, the new property value is not copied into the property and the set routine returns an error value. The set routine will be called for the initial value.

Note: The set callback function may be useful to range check the value being set for the property or may perform some transformation or translation of the value set. The get callback would then reverse the transformation or translation. A single get or set callback could handle multiple properties by performing different actions based on the property name or other properties in the property list.

The get routine is called when a value is retrieved from a property value. The H5P_prp_get_func_t callback function is defined as follows:

The parameters to the above callback function are:

The get routine may modify the value to be returned from the query and those changes will be preserved. If the get routine returns a negative value, the query routine returns an error value.

The delete routine is called when a property is being deleted from a property list. The H5P_prp_delete_func_t callback function is defined as follows:

The parameters to the above callback function are:

The delete routine may modify the value passed in, but the value is not used by the library when the delete routine returns. If the delete routine returns a negative value, the property list delete routine returns an error value but the property is still deleted.

The copy routine is called when a new property list with this property is being created through a copy operation. The H5P_prp_copy_func_t callback function is defined as follows:

The parameters to the above callback function are:

The copy routine may modify the value to be set and those changes will be stored as the new value of the property. If the copy routine returns a negative value, the new property value is not copied into the property and the copy routine returns an error value.

The close routine is called when a property list with this property is being closed. The H5P_prp_close_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The close routine may modify the value passed in, the value is not used by the library when the close routine returns. If the close routine returns a negative value, the property list close routine returns an error value but the property list is still closed.

Note: There is no create callback routine for temporary property list objects; the initial value is assumed to have any necessary setup already performed on it.

Programming Note for C++ Developers Using C Functions:

If a C routine that takes a function pointer as an argument is called from within C++ code, the C routine should be returned from normally.

Examples of this kind of routine include callbacks such as H5Pset_elink_cb and H5Pset_type_conv_cb and functions such as H5Tconvert and H5Ewalk2.

Exiting the routine in its normal fashion allows the HDF5 C Library to clean up its work properly. In other words, if the C++ application jumps out of the routine back to the C++ “catch” statement, the library is not given the opportunity to close any temporary data structures that were set up when the routine was called. The C++ application should save some state as the routine is started so that any problem that occurs might be diagnosed.

Parameters:

Returns:
Success: a non-negative value
Failure: a negative value

Fortran90 Interface: h5pinsert_f
SUBROUTINE h5pinsert_f
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist   ! Property list class identifier 
  CHARACTER(LEN=*), INTENT(IN) :: name  ! Name of property to insert
  INTEGER(SIZE_T), INTENT(IN) :: size   ! Size of the property value	
  TYPE,   INTENT(IN) :: value           ! Property value
                                        ! Supported types are:
                                        !    INTEGER
                                        !    REAL
                                        !    DOUBLE PRECISION
                                        !    CHARACTER(LEN=*)
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pinsert_f
	

History:

Last modified: 23 August 2012
Name: H5Pinsert2
Signature:
herr_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 )

Purpose:
Registers a temporary property with a property list.

Description:
H5Pinsert2 create a new property in a property list. The property will exist only in this property list and copies made from it.

The initial property value must be provided in value and the property value will be set accordingly.

The name of the property must not already exist in this list, or this routine will fail.

The set and get callback routines may be set to NULL if they are not needed.

Zero-sized properties are allowed and do not store any data in the property list. The default value of a zero-size property may be set to NULL. They may be used to indicate the presence or absence of a particular piece of information.

The set routine is called before a new value is copied into the property. The H5P_prp_set_func_t callback function is defined as follows: The parameters to the callback function are defined as follows: The set routine may modify the value pointer to be set and those changes will be used when setting the property's value. If the set routine returns a negative value, the new property value is not copied into the property and the set routine returns an error value. The set routine will be called for the initial value.

Note: The set callback function may be useful to range check the value being set for the property or may perform some transformation or translation of the value set. The get callback would then reverse the transformation or translation. A single get or set callback could handle multiple properties by performing different actions based on the property name or other properties in the property list.

The get routine is called when a value is retrieved from a property value. The H5P_prp_get_func_t callback function is defined as follows:

The parameters to the above callback function are:

The get routine may modify the value to be returned from the query and those changes will be preserved. If the get routine returns a negative value, the query routine returns an error value.

The delete routine is called when a property is being deleted from a property list. The H5P_prp_delete_func_t callback function is defined as follows:

The parameters to the above callback function are:

The delete routine may modify the value passed in, but the value is not used by the library when the delete routine returns. If the delete routine returns a negative value, the property list delete routine returns an error value but the property is still deleted.

The copy routine is called when a new property list with this property is being created through a copy operation. The H5P_prp_copy_func_t callback function is defined as follows:

The parameters to the above callback function are:

The copy routine may modify the value to be set and those changes will be stored as the new value of the property. If the copy routine returns a negative value, the new property value is not copied into the property and the copy routine returns an error value.

The compare routine is called when a property list with this property is compared to another property list with the same property. The H5P_prp_compare_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The compare routine may not modify the values. The compare routine should return a positive value if value1 is greater than value2, a negative value if value2 is greater than value1 and zero if value1 and value2 are equal.

The close routine is called when a property list with this property is being closed. The H5P_prp_close_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The close routine may modify the value passed in, the value is not used by the library when the close routine returns. If the close routine returns a negative value, the property list close routine returns an error value but the property list is still closed.

Note: There is no create callback routine for temporary property list objects; the initial value is assumed to have any necessary setup already performed on it.

Programming Note for C++ Developers Using C Functions:

If a C routine that takes a function pointer as an argument is called from within C++ code, the C routine should be returned from normally.

Examples of this kind of routine include callbacks such as H5Pset_elink_cb and H5Pset_type_conv_cb and functions such as H5Tconvert and H5Ewalk2.

Exiting the routine in its normal fashion allows the HDF5 C Library to clean up its work properly. In other words, if the C++ application jumps out of the routine back to the C++ “catch” statement, the library is not given the opportunity to close any temporary data structures that were set up when the routine was called. The C++ application should save some state as the routine is started so that any problem that occurs might be diagnosed.

Parameters:

Returns:
Success: a non-negative value
Failure: a negative value

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.

Last modified: 20 April 2009
Name: H5Pisa_class
Signature:
htri_t H5Pisa_class( hid_t plist, hid_t pclass )

Purpose:
Determines whether a property list is a member of a class.

Description:
H5Pisa_class checks to determine whether the property list plist is a member of the property list class pclass.

Parameters:
hid_t plist IN: Property list identifier
hid_t pclass     IN: Property list class identifier

Returns:
Returns a positive value if true or zero if false; returns a negative value on failure.

See Also:
H5Pcreate

Fortran90 Interface: h5pisa_class_f
SUBROUTINE h5pisa_class_f(plist, pclass, flag, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist     ! Property list identifier 
  INTEGER(HID_T), INTENT(IN) :: pclass    ! Class identifier
  LOGICAL, INTENT(OUT) :: flag            ! Logical flag
                                          !    .TRUE. if a member
                                          !    .FALSE. otherwise
  INTEGER, INTENT(OUT) :: hdferr          ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pisa_class_f
	

Last modified: 23 August 2012
Name: H5Piterate
Purpose:
Iterates over properties in a property class or list.
Signature:
int H5Piterate( hid_t id, int * idx, H5P_iterate_t iter_func, void * iter_data )
Description:

H5Piterate iterates over the properties in the property object specified in id, which may be either a property list or a property class, performing a specified operation on each property in turn.

For each property in the object, iter_func and the additional information specified below are passed to the H5P_iterate_t operator function.

The iteration begins with the idx-th property in the object; the next element to be processed by the operator is returned in idx. If idx is NULL, the iterator starts at the first property; since no stopping point is returned in this case, the iterator cannot be restarted if one of the calls to its operator returns non-zero.

The prototype for the H5P_iterate_t operator is as follows: The operation receives the property list or class identifier for the object being iterated over, id, the name of the current property within the object, name, and the pointer to the operator data passed in to H5Piterate, iter_data.

The valid return values from an operator are as follows:

H5Piterate assumes that the properties in the object identified by id remain unchanged through the iteration. If the membership changes during the iteration, the function's behavior is undefined.

Programming Note for C++ Developers Using C Functions:

If a C routine that takes a function pointer as an argument is called from within C++ code, the C routine should be returned from normally.

Examples of this kind of routine include callbacks such as H5Pset_elink_cb and H5Pset_type_conv_cb and functions such as H5Tconvert and H5Ewalk2.

Exiting the routine in its normal fashion allows the HDF5 C Library to clean up its work properly. In other words, if the C++ application jumps out of the routine back to the C++ “catch” statement, the library is not given the opportunity to close any temporary data structures that were set up when the routine was called. The C++ application should save some state as the routine is started so that any problem that occurs might be diagnosed.

Parameters:
Returns:
Success: the return value of the last call to iter_func if it was non-zero; zero if all properties have been processed
Failure: a negative value
Fortran90 Interface:
None.

Last modified: 10 June 2010
Name: H5Pmodify_filter
Signature:
herr_t H5Pmodify_filter( hid_t plist_id, H5Z_filter_t filter_id, unsigned int flags, size_t cd_nelmts, const unsigned int cd_values[] )

Purpose:
Modifies a filter in the filter pipeline.

Description:
H5Pmodify_filter modifies the specified filter_id in the filter pipeline. plist_id must be a dataset or group creation property list.

The filter_id, flags cd_nelmts[], and cd_values parameters are used in the same manner and accept the same values as described in the discussion of H5Pset_filter.

Parameters:

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pmodify_filter_f
SUBROUTINE h5pmodify_filter_f(prp_id, filter, flags, cd_nelmts, & 
                              cd_values, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id      ! Property list identifier
  INTEGER, INTENT(IN)        :: filter      ! Filter to be modified
  INTEGER, INTENT(IN)        :: flags       ! Bit vector specifying certain 
                                            ! general properties of the filter
  INTEGER(SIZE_T), INTENT(IN) :: cd_nelmts  ! Number of elements in cd_values
  INTEGER, DIMENSION(*), INTENT(IN) :: cd_values  
                                            ! Auxiliary data for the filter
  INTEGER, INTENT(OUT)       :: hdferr      ! Error code
                                            ! 0 on success and -1 on failure
END SUBROUTINE h5pmodify_filter_f
    

History:

Last modified: 26 March 2014
Name: H5Pregister
Signatures:
herr_t H5Pregister( 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_close_func_t close )
 
[1]
herr_t H5Pregister( 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 ) [2]
Purpose:
Registers a permanent property with a property list class.

Description:
H5Pregister is a macro that is mapped to either H5Pregister1 or H5Pregister2, depending on the needs of the application.

Such macros are provided to facilitate application compatibility. For example:

When both the HDF5 Library and the application are built and installed with no specific compatibility flags, H5Pregister is mapped to the most recent version of the function, currently H5Pregister2. If the library and/or application is compiled for Release 1.6 emulation, H5Pregister will be mapped to H5Pregister1. Function-specific flags are available to override these settings on a function-by-function basis when the application is compiled.

Specific compile-time compatibility flags and the resulting mappings are as follows:

Compatibility setting H5Pregister mapping

Global settings
No compatibility flag H5Pregister2 
Enable deprecated symbols H5Pregister2 
Disable deprecated symbols H5Pregister2 
Emulate Release 1.6 interface H5Pregister1 

Function-level macros
H5Pregister_vers = 2     H5Pregister2
H5Pregister_vers = 1 H5Pregister1

For more information on macro use and mappings, see the “API Compatibility Macros in HDF5” document.

Interface history:   Signature [1] above is the original H5Pregister interface and the only interface available prior to HDF5 Release 1.8.0. This signature and the corresponding function are now deprecated but will remain directly callable as H5Pregister1.

Signature [2] above was introduced with HDF5 Release 1.8.0 and is the recommended and default interface. It is directly callable as H5Pregister2.

See “API Compatibility Macros in HDF5” for circumstances under which either of these functions might not be available in an installed instance of the HDF5 Library.

Programming Note for C++ Developers Using C Functions:

If a C routine that takes a function pointer as an argument is called from within C++ code, the C routine should be returned from normally.

Examples of this kind of routine include callbacks such as H5Pset_elink_cb and H5Pset_type_conv_cb and functions such as H5Tconvert and H5Ewalk2.

Exiting the routine in its normal fashion allows the HDF5 C Library to clean up its work properly. In other words, if the C++ application jumps out of the routine back to the C++ “catch” statement, the library is not given the opportunity to close any temporary data structures that were set up when the routine was called. The C++ application should save some state as the routine is started so that any problem that occurs might be diagnosed.

Fortran90 Interface: h5pregister_f
Signature:

  SUBROUTINE h5pregister_f(class, name, size, value, hdferr)
    INTEGER(HID_T)  , INTENT(IN)  :: class
    CHARACTER(LEN=*), INTENT(IN)  :: name
    INTEGER(SIZE_T) , INTENT(IN)  :: size
    TYPE            , INTENT(IN)  :: value
    INTEGER         , INTENT(OUT) :: hdferr  

Inputs:

  class  - Property list class identifier
  name   - Name of property to register
  size   - Size of the property value
  value  - Property value, supported types are:
             INTEGER
             REAL
             DOUBLE PRECISION
             CHARACTER(LEN=*)

Outputs:

  hdferr - Returns 0 if successful and -1 if fails

Fortran2003 Interface: h5pregister_f
Signature:

  SUBROUTINE h5pregister_f(class, name, size, value, hdferr)
    INTEGER(HID_T)  , INTENT(IN)  :: class
    CHARACTER(LEN=*), INTENT(IN)  :: name
    INTEGER(SIZE_T) , INTENT(IN)  :: size
    TYPE(C_PTR)     , INTENT(IN)  :: value
    INTEGER         , INTENT(OUT) :: hdferr  

Inputs:

  class  - Property list class identifier
  name   - Name of property to register
  size   - Size of the property value
  value  - Pointer to value to set the property to

Outputs:

  hdferr - Returns 0 if successful and -1 if fails

History:
Release     C
1.8.8 Fortran updated to Fortran2003.
1.8.0 The function C function H5Pregister renamed to H5Pregister1 and deprecated in this release.
C macro H5Pregister and C function H5Pregister2 introduced in this release.

Last modified: 23 August 2012
Name: H5Pregister1
Signature:
herr_t H5Pregister1( 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_close_func_t close )

Purpose:
Registers a permanent property with a property list class.

Notice:
This function is renamed from H5Pregister and deprecated in favor of the function H5Pregister2 and or the new macro H5Pregister.

Description:
H5Pregister1 registers a new property with a property list class. The property will exist in all property list objects of class created after this routine finishes. The name of the property must not already exist, or this routine will fail. The default property value must be provided and all new property lists created with this property will have the property value set to the default value. Any of the callback routines may be set to NULL if they are not needed.

Zero-sized properties are allowed and do not store any data in the property list. These may be used as flags to indicate the presence or absence of a particular piece of information. The default pointer for a zero-sized property may be set to NULL. The property create and close callbacks are called for zero-sized properties, but the set and get callbacks are never called.

The create routine is called when a new property list with this property is being created. The H5P_prp_create_func_t callback function is defined as follows:

The parameters to this callback function are defined as follows: The create routine may modify the value to be set and those changes will be stored as the initial value of the property. If the create routine returns a negative value, the new property value is not copied into the property and the create routine returns an error value.

The set routine is called before a new value is copied into the property. The H5P_prp_set_func_t callback function is defined as follows:

The parameters to this callback function are defined as follows: The set routine may modify the value pointer to be set and those changes will be used when setting the property's value. If the set routine returns a negative value, the new property value is not copied into the property and the set routine returns an error value. The set routine will not be called for the initial value, only the create routine will be called.

Note: The set callback function may be useful to range check the value being set for the property or may perform some transformation or translation of the value set. The get callback would then reverse the transformation or translation. A single get or set callback could handle multiple properties by performing different actions based on the property name or other properties in the property list.

The get routine is called when a value is retrieved from a property value. The H5P_prp_get_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The get routine may modify the value to be returned from the query and those changes will be returned to the calling routine. If the set routine returns a negative value, the query routine returns an error value.

The delete routine is called when a property is being deleted from a property list. The H5P_prp_delete_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The delete routine may modify the value passed in, but the value is not used by the library when the delete routine returns. If the delete routine returns a negative value, the property list delete routine returns an error value but the property is still deleted.

The copy routine is called when a new property list with this property is being created through a copy operation. The H5P_prp_copy_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The copy routine may modify the value to be set and those changes will be stored as the new value of the property. If the copy routine returns a negative value, the new property value is not copied into the property and the copy routine returns an error value.

The close routine is called when a property list with this property is being closed. The H5P_prp_close_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The close routine may modify the value passed in, but the value is not used by the library when the close routine returns. If the close routine returns a negative value, the property list close routine returns an error value but the property list is still closed.

Programming Note for C++ Developers Using C Functions:

If a C routine that takes a function pointer as an argument is called from within C++ code, the C routine should be returned from normally.

Examples of this kind of routine include callbacks such as H5Pset_elink_cb and H5Pset_type_conv_cb and functions such as H5Tconvert and H5Ewalk2.

Exiting the routine in its normal fashion allows the HDF5 C Library to clean up its work properly. In other words, if the C++ application jumps out of the routine back to the C++ “catch” statement, the library is not given the opportunity to close any temporary data structures that were set up when the routine was called. The C++ application should save some state as the routine is started so that any problem that occurs might be diagnosed.

Parameters:

Returns:
Success: a non-negative value
Failure: a negative value

Fortran90 Interface: h5pregister_f
SUBROUTINE h5pregister_f
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: class   ! Property list class identifier 
  CHARACTER(LEN=*), INTENT(IN) :: name  ! Name of property to register
  INTEGER(SIZE_T), INTENT(IN) :: size   ! Size of the property value	
  TYPE,   INTENT(IN) :: value           ! Property value
                                        ! Supported types are:
                                        !    INTEGER
                                        !    REAL
                                        !    DOUBLE PRECISION
                                        !    CHARACTER(LEN=*)
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pregister_f
	

History:
Release     C
1.8.0 Function H5Pregister renamed to H5Pregister1 and deprecated in this release.

Last modified: 23 August 2012
Name: H5Pregister2
Signature:
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 )

Purpose:
Registers a permanent property with a property list class.

Description:
H5Pregister2 registers a new property with a property list class. The property will exist in all property list objects of class created after this routine finishes. The name of the property must not already exist, or this routine will fail. The default property value must be provided and all new property lists created with this property will have the property value set to the default value. Any of the callback routines may be set to NULL if they are not needed.

Zero-sized properties are allowed and do not store any data in the property list. These may be used as flags to indicate the presence or absence of a particular piece of information. The default pointer for a zero-sized property may be set to NULL. The property create and close callbacks are called for zero-sized properties, but the set and get callbacks are never called.

The create routine is called when a new property list with this property is being created. The H5P_prp_create_func_t callback function is defined as follows:

The parameters to this callback function are defined as follows: The create routine may modify the value to be set and those changes will be stored as the initial value of the property. If the create routine returns a negative value, the new property value is not copied into the property and the create routine returns an error value.

The set routine is called before a new value is copied into the property. The H5P_prp_set_func_t callback function is defined as follows:

The parameters to this callback function are defined as follows: The set routine may modify the value pointer to be set and those changes will be used when setting the property's value. If the set routine returns a negative value, the new property value is not copied into the property and the set routine returns an error value. The set routine will not be called for the initial value, only the create routine will be called.

Note: The set callback function may be useful to range check the value being set for the property or may perform some transformation or translation of the value set. The get callback would then reverse the transformation or translation. A single get or set callback could handle multiple properties by performing different actions based on the property name or other properties in the property list.

The get routine is called when a value is retrieved from a property value. The H5P_prp_get_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The get routine may modify the value to be returned from the query and those changes will be returned to the calling routine. If the set routine returns a negative value, the query routine returns an error value.

The delete routine is called when a property is being deleted from a property list. The H5P_prp_delete_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The delete routine may modify the value passed in, but the value is not used by the library when the delete routine returns. If the delete routine returns a negative value, the property list delete routine returns an error value but the property is still deleted.

The copy routine is called when a new property list with this property is being created through a copy operation. The H5P_prp_copy_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The copy routine may modify the value to be set and those changes will be stored as the new value of the property. If the copy routine returns a negative value, the new property value is not copied into the property and the copy routine returns an error value.

The compare routine is called when a property list with this property is compared to another property list with the same property. The H5P_prp_compare_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The compare routine may not modify the values. The compare routine should return a positive value if value1 is greater than value2, a negative value if value2 is greater than value1 and zero if value1 and value2 are equal.

The close routine is called when a property list with this property is being closed. The H5P_prp_close_func_t callback function is defined as follows:

The parameters to the callback function are defined as follows: The close routine may modify the value passed in, but the value is not used by the library when the close routine returns. If the close routine returns a negative value, the property list close routine returns an error value but the property list is still closed.

Programming Note for C++ Developers Using C Functions:

If a C routine that takes a function pointer as an argument is called from within C++ code, the C routine should be returned from normally.

Examples of this kind of routine include callbacks such as H5Pset_elink_cb and H5Pset_type_conv_cb and functions such as H5Tconvert and H5Ewalk2.

Exiting the routine in its normal fashion allows the HDF5 C Library to clean up its work properly. In other words, if the C++ application jumps out of the routine back to the C++ “catch” statement, the library is not given the opportunity to close any temporary data structures that were set up when the routine was called. The C++ application should save some state as the routine is started so that any problem that occurs might be diagnosed.

Parameters:

Returns:
Success: a non-negative value
Failure: a negative value

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Premove
Signature:
herr_t H5Premove( hid_t plid; const char *name )
Purpose:
Removes a property from a property list.
Description:
H5Premove removes a property from a property list.

Both properties which were in existence when the property list was created (i.e. properties registered with H5Pregister) and properties added to the list after it was created (i.e. added with H5Pinsert1) may be removed from a property list. Properties do not need to be removed from a property list before the list itself is closed; they will be released automatically when H5Pclose is called.

If a close callback exists for the removed property, it will be called before the property is released.

Parameters:
Returns:
Success: a non-negative value
Failure: a negative value
Fortran90 Interface: h5premove_f
SUBROUTINE h5premove_f(plid, name, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plid   ! Property list identifier
  CHARACTER(LEN=*), INTENT(IN) :: name ! Name of property to remove
  INTEGER, INTENT(OUT) :: hdferr       ! Error code
                                       ! 0 on success and -1 on failure
END SUBROUTINE h5premove_f
	

Last modified: 10 June 2010
Name: H5Premove_filter
Signature:
herr_t H5Premove_filter( hid_t plist_id, H5Z_filter_t filter )

Purpose:
Delete one or more filters in the filter pipeline.

Description:
H5Premove_filter removes the specified filter from the filter pipeline in the dataset or group creation property list plist_id.

The filter parameter specifies the filter to be removed. Valid values for use in filter are as follows:

H5Z_FILTER_ALL Removes all filters from the filter pipeline.
H5Z_FILTER_DEFLATE Data compression filter, employing the gzip algorithm
H5Z_FILTER_SHUFFLE Data shuffling filter
H5Z_FILTER_FLETCHER32 Error detection filter, employing the Fletcher32 checksum algorithm
H5Z_FILTER_SZIP Data compression filter, employing the SZIP algorithm
H5Z_FILTER_NBIT Data compression filter, employing the N-Bit algorithm
H5Z_FILTER_SCALEOFFSET   Data compression filter, employing the scale-offset algorithm

Additionally, user-defined filters can be removed with this routine by passing the filter identifier with which they were registered with the HDF5 Library.

Attempting to remove a filter that is not in the filter pipeline is an error.

Parameters:
hid_t plist_id
IN: Dataset or group creation property list identifier.
H5Z_filter_t filter
IN: Filter to be deleted.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5premove_filter_f
SUBROUTINE h5premove_filter_f(prp_id, filter, hdferr) 

  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier
  INTEGER, INTENT(IN) :: filter        ! Filter to be removed
                                       ! Valid values are:
                                       !     H5Z_FILTER_ALL_F
                                       !     H5Z_FILTER_DEFLATE_F
                                       !     H5Z_FILTER_SHUFFLE_F
                                       !     H5Z_FILTER_FLETCHER32_F
                                       !     H5Z_FILTER_SZIP_F
  INTEGER, INTENT(OUT) :: hdferr       ! Error code
                                       ! 0 on success, -1 on failure
END SUBROUTINE h5premove_filter_f
    

History:
Release     Changes
1.6.3 Function introduced in this release.
Fortran subroutine introduced in this release.
1.8.5 Function extended to work with group creation property lists.

Last modified: 29 September 2011
Name: H5Pset
Signature:
herr_t H5Pset( hid_t plid, const char *name, void *value) )

Purpose:
Sets a property list value.

Description:
H5Pset sets a new value for a property in a property list. If there is a set callback routine registered for this property, the value will be passed to that routine and any changes to the value will be used when setting the property value. The information pointed to by the value pointer (possibly modified by the set callback) is copied into the property list value and may be changed by the application making the H5Pset call without affecting the property value.

The property name must exist or this routine will fail.

If the set callback routine returns an error, the property value will not be modified.

This routine may not be called for zero-sized properties and will return an error in that case.

Parameters:
hid_t plid; IN: Property list identifier to modify
const char *name;     IN: Name of property to modify
void *value; IN: Pointer to value to set the property to

Returns:
Success: a non-negative value
Failure: a negative value

Fortran90 Interface: h5pset_f
Signature:

  SUBROUTINE h5pset_f(plid, name, value, hdferr)
    INTEGER(HID_T)  , INTENT(IN)  :: plid
    CHARACTER(LEN=*), INTENT(IN)  :: name
    TYPE            , INTENT(IN)  :: value
    INTEGER         , INTENT(OUT) :: hdferr

Inputs:

  prp_id  - Property list identifier to modify
  name    - Name of property to modify
  value   - Property value, supported types are:
             INTEGER
             REAL
             DOUBLE PRECISION
             CHARACTER(LEN=*)

Outputs:

  hdferr  - Returns 0 if successful and -1 if fails

Fortran2003 Interface: h5pset_f
Signature:

  SUBROUTINE h5pset_f(plid, name, value, hdferr)
    INTEGER(HID_T)  , INTENT(IN)  :: plid
    CHARACTER(LEN=*), INTENT(IN)  :: name
    TYPE(C_PTR)     , INTENT(IN)  :: value
    INTEGER         , INTENT(OUT) :: hdferr

Inputs:

  prp_id  - Property list identifier to modify
  name    - Name of property to modify
  value   - Pointer to value to set the property to

Outputs:

  hdferr  - Returns 0 if successful and -1 if fails

History:
Release     Change
1.8.8 Fortran updated to Fortran2003.

Name: H5Pset_alignment
Signature:
herr_t H5Pset_alignment(hid_t plist, hsize_t threshold, hsize_t alignment )
Purpose:
Sets alignment properties of a file access property list.
Description:
H5Pset_alignment sets the alignment properties of a file access property list so that any file object greater than or equal in size to threshold bytes will be aligned on an address which is a multiple of alignment. The addresses are relative to the end of the user block; the alignment is calculated by subtracting the user block size from the absolute file address and then adjusting the address to be a multiple of alignment.

Default values for threshold and alignment are one, implying no alignment. Generally the default values will result in the best performance for single-process access to the file. For MPI IO and other parallel systems, choose an alignment which is a multiple of the disk block size.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pset_alignment_f
SUBROUTINE h5pset_alignment_f(prp_id, threshold,  alignment, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id       ! Property list identifier
  INTEGER(HSIZE_T), INTENT(IN) :: threshold  ! Threshold value
  INTEGER(HSIZE_T), INTENT(IN) :: alignment  ! Alignment value
  INTEGER, INTENT(OUT) :: hdferr             ! Error code
                                             ! 0 on success and -1 on failure
END SUBROUTINE h5pset_alignment_f
	

Name: H5Pset_alloc_time
Signature:
herr_t H5Pset_alloc_time(hid_t plist_id, H5D_alloc_time_t alloc_time )
Purpose:
Sets the timing for storage space allocation.
Description:
H5Pset_alloc_time sets up the timing for the allocation of storage space for a dataset's raw data. This property is set in the dataset creation property list plist_id.

Timing is specified in alloc_time with one of the following values:
     H5D_ALLOC_TIME_DEFAULT   Allocate dataset storage space at the default time.
(Defaults differ by storage method.)
H5D_ALLOC_TIME_EARLY Allocate all space when the dataset is created.
(Default for compact datasets.)
H5D_ALLOC_TIME_INCR   Allocate space incrementally, as data is written to the dataset.
(Default for chunked storage datasets.)
  • Chunked datasets: Storage space allocation for each chunk is deferred until data is written to the chunk.
  • Contiguous datasets: Incremental storage space allocation for contiguous data is treated as late allocation.
  • Compact datasets: Incremental allocation is not allowed with compact datasets; H5Pset_alloc_time will return an error.
H5D_ALLOC_TIME_LATE Allocate all space when data is first written to the dataset.
(Default for contiguous datasets.)

Note:
H5Pset_alloc_time is designed to work in concert with the dataset fill value and fill value write time properties, set with the functions H5Pset_fill_value and H5Pset_fill_time.

See H5Dcreate for further cross-references.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pset_alloc_time_f
SUBROUTINE h5pset_alloc_time_f(plist_id, flag, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id  ! Dataset creation property
                                          ! list identifier
  INTEGER(HSIZE_T), INTENT(IN) :: flag    ! Allocation time flag
                                          ! Possible values are:
                                          !    H5D_ALLOC_TIME_ERROR_F
                                          !    H5D_ALLOC_TIME_DEFAULT_F
                                          !    H5D_ALLOC_TIME_EARLY_F
                                          !    H5D_ALLOC_TIME_LATE_F
                                          !    H5D_ALLOC_TIME_INCR_F
  INTEGER, INTENT(OUT)       :: hdferr    ! Error code
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pset_alloc_time_f
	
History:

Last modified: 20 March 2012
Name: H5Pset_attr_creation_order
Signature:
herr_t H5Pset_attr_creation_order( hid_t ocpl_id, unsigned crt_order_flags )

Purpose:
Sets tracking and indexing of attribute creation order.

Description:
H5Pset_attr_creation_order sets flags for tracking and indexing attribute creation order on an object.

ocpl_id is a dataset or group creation property list identifier. The term ocpl, for object creation property list, is used when more than one type of object may be involved.

crt_order_flags contains flags with the following meanings:
     H5P_CRT_ORDER_TRACKED Attribute creation order is tracked but not necessarily indexed.
     H5P_CRT_ORDER_INDEXED     Attribute creation order is indexed (requires H5P_CRT_ORDER_TRACKED).
Default behavior is that attribute creation order is neither tracked nor indexed.

H5Pset_attr_creation_order can be used to set attribute creation order tracking, or to set attribute creation order tracking and indexing.

Note that if a creation order index is to be built, it must be specified in the object creation property list. HDF5 currently provides no mechanism to turn on attribute creation order tracking at object creation time and to build the index later.

Parameters:
hid_t ocpl_id IN: Object creation property list identifier
unsigned crt_order_flags     IN: Flags specifying whether to track and index attribute creation order
Default: No flag set; attribute creation order is neither tracked not indexed.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_attr_creation_order_f
SUBROUTINE h5pset_attr_creation_order_f(ocpl_id, crt_order_flags , hdferr)
  IMPLICIT NONE 
  INTEGER(HID_T), INTENT(IN) :: ocpl_id   ! Object (dataset or group) creation 
                                          ! property list identifier
  INTEGER, INTENT(IN) :: crt_order_flags  ! Flags specifying whether to track 
                                          ! and index attribute creation order
  INTEGER, INTENT(OUT) :: hdferr          ! Error code 
                                          ! 0 on success and -1 on failure
END SUBROUTINE h5pset_attr_creation_order_f
    

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pset_attr_phase_change
Signature:
herr_t H5Pset_attr_phase_change( hid_t ocpl_id, unsigned max_compact, unsigned min_dense )

Purpose:
Sets attribute storage phase change thresholds.

Description:
H5Pset_attr_phase_change sets threshold values for attribute storage on an object. These thresholds determine the point at which attribute storage changes from compact storage (i.e., storage in the object header) to dense storage (i.e., storage in a heap and indexed with a B-tree).

In the general case, attributes are initially kept in compact storage. When the number of attributes exceeds max_compact, attribute storage switches to dense storage. If the number of attributes subsequently falls below min_dense, the attributes are returned to compact storage.

If max_compact is set to 0 (zero), dense storage always used.

ocpl_id is a dataset or group creation property list identifier. The term ocpl, for object creation property list, is used when different types of objects may be involved.

Parameters:
hid_t ocpl_id IN: Object (group or dataset) creation property list identifier
unsigned max_compact    IN: Maximum number of attributes to be stored in compact storage
(Default: 8)
unsigned min_dense     IN: Minimum number of attributes to be stored in dense storage
(Default: 6)

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_attr_phase_change_f
SUBROUTINE h5pset_attr_phase_change_f(ocpl_id, max_compact, min_dense, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: ocpl_id 
                              ! Object (dataset or group) creation property 
                              ! list identifier
  INTEGER, INTENT(IN) :: max_compact  
                              ! Maximum number of attributes to be stored in 
                              ! compact storage (Default: 8)
  INTEGER, INTENT(IN) :: min_dense  
                              ! Minimum number of attributes to be stored in 
                              ! dense storage (Default: 6)
  INTEGER, INTENT(OUT) :: hdferr 
                              ! Error code
                              ! 0 on success and -1 on failure
END SUBROUTINE h5pset_attr_phase_change_f
    

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pset_btree_ratios
Signature:
herr_t H5Pset_btree_ratios(hid_t plist, double left, double middle, double right )
Purpose:
Sets B-tree split ratios for a dataset transfer property list.
Description:
H5Pset_btree_ratios sets the B-tree split ratios for a dataset transfer property list. The split ratios determine what percent of children go in the first node when a node splits.

The ratio left is used when the splitting node is the left-most node at its level in the tree; the ratio right is used when the splitting node is the right-most node at its level; and the ratio middle is used for all other cases.

A node which is the only node at its level in the tree uses the ratio right when it splits.

All ratios are real numbers between 0 and 1, inclusive.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pset_btree_ratios_f
SUBROUTINE h5pset_btree_ratios_f(prp_id, left, middle, right, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id   
                                  ! Property list identifier
  REAL, INTENT(IN) :: left        ! The B-tree split ratio for left-most nodes
  REAL, INTENT(IN) :: middle      ! The B-tree split ratio for all other nodes
  REAL, INTENT(IN) :: right       ! The B-tree split ratio for right-most
                                  ! nodes and lone nodes.
  INTEGER, INTENT(OUT) :: hdferr  ! Error code
                                  ! 0 on success and -1 on failure
END SUBROUTINE h5pset_btree_ratios_f
	

Name: H5Pset_buffer
Signature:
herr_t H5Pset_buffer(hid_t plist, hsize_t size, void *tconv, void *bkg )
Purpose:
Sets type conversion and background buffers.
Description:
Given a dataset transfer property list, H5Pset_buffer sets the maximum size for the type conversion buffer and background buffer and optionally supplies pointers to application-allocated buffers. If the buffer size is smaller than the entire amount of data being transferred between the application and the file, and a type conversion buffer or background buffer is required, then strip mining will be used.

Note that there are minimum size requirements for the buffer. Strip mining can only break the data up along the first dimension, so the buffer must be large enough to accommodate a complete slice that encompasses all of the remaining dimensions. For example, when strip mining a 100x200x300 hyperslab of a simple data space, the buffer must be large enough to hold 1x200x300 data elements. When strip mining a 100x200x300x150 hyperslab of a simple data space, the buffer must be large enough to hold 1x200x300x150 data elements.

If tconv and/or bkg are null pointers, then buffers will be allocated and freed during the data transfer.

The default value for the maximum buffer is 1 Mb.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pset_buffer_f
SUBROUTINE h5pset_buffer_f(plist_id, size, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN)   :: plist_id ! Dataset transfer property 
                                           ! list identifier
  INTEGER(HSIZE_T), INTENT(IN) :: size     ! Conversion buffer size
  INTEGER, INTENT(OUT)         :: hdferr   ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pset_buffer_f
	
History:

Last modified: 22 July 2014
Name: H5Pset_cache

Signature:
herr_t H5Pset_cache(hid_t plist_id, int mdc_nelmts, size_t rdcc_nslots, size_t rdcc_nbytes, double rdcc_w0)

Purpose:
Sets the raw data chunk cache parameters.

Motivation:
Setting raw data chunk cache parameters can be done with H5Pset_cache, H5Pset_chunk_cache, or a combination of both. H5Pset_cache is used to adjust the chunk cache parameters for all datasets via a global setting for the file, and H5Pset_chunk_cache is used to adjust the chunk cache parameters for individual datasets. When both are used, parameters set with H5Pset_chunk_cache will override any parameters set with H5Pset_cache.

Optimum chunk cache parameters may vary widely depending on different data layout and access patterns. For datasets with low performance requirements for example, changing the cache settings can save memory.

Description:
H5Pset_cache sets the number of elements, the total number of bytes, and the preemption policy value for all datasets in a file on the file’s file access property list.

The raw data chunk cache inserts chunks into the cache by first computing a hash value using the address of a chunk and then by using that hash value as the chunk’s index into the table of cached chunks. In other words, the size of this hash table and the number of possible hash values is determined by the rdcc_nslots parameter. If a different chunk in the cache has the same hash value, a collision will occur, which will reduce efficiency. If inserting the chunk into the cache would cause the cache to be too big, then the cache will be pruned according to the rdcc_w0 parameter.

The mdc_nelmts parameter is no longer used; any value passed in that parameter will be ignored.

Note:
Raw dataset chunk caching is not currently supported when using the MPI I/O and MPI POSIX file drivers in read/write mode; see H5Pset_fapl_mpio and H5Pset_fapl_mpiposix, respectively. When using one of these file drivers, all calls to H5Dread and H5Dwrite will access the disk directly, and H5Pset_cache will have no effect on performance.

Raw dataset chunk caching is supported when these drivers are used in read-only mode.


Parameters:
hid_t plist_id IN: File access property list identifier.
int mdc_nelmts IN: No longer used; any value passed is ignored.
size_t rdcc_nslots IN: The number of chunk slots in the raw data chunk cache for this dataset. Increasing this value reduces the number of cache collisions, but slightly increases the memory used. Due to the hashing strategy, this value should ideally be a prime number. As a rule of thumb, this value should be at least 10 times the number of chunks that can fit in rdcc_nbytes bytes. For maximum performance, this value should be set approximately 100 times that number of chunks. The default value is 521.
size_t rdcc_nbytes IN: Total size of the raw data chunk cache in bytes. The default size is 1 MB per dataset.
double rdcc_w0 IN: The chunk preemption policy for all datasets. This must be between 0 and 1 inclusive and indicates the weighting according to which chunks which have been fully read or written are penalized when determining which chunks to flush from cache. A value of 0 means fully read or written chunks are treated no differently than other chunks (the preemption is strictly LRU) while a value of 1 means fully read or written chunks are always preempted before other chunks. If your application only reads or writes data once, this can be safely set to 1. Otherwise, this should be set lower depending on how often you re-read or re-write the same data.

The default value is 0.75. If the value passed is H5D_CHUNK_CACHE_W0_DEFAULT, then the property will not be set on dapl_id, and the parameter will come from the file access property list.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_cache_f
SUBROUTINE h5pset_cache_f(prp_id, mdc_nelmts, rdcc_nslots, rdcc_nbytes, rdcc_w0, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id        ! Property list identifier
  INTEGER, INTENT(IN) :: mdc_nelmts           ! No longer used; any value passed
                                              ! is ignored.
  INTEGER(SIZE_T), INTENT(IN) :: rdcc_nslots  ! The number of chunk slots
                                              ! in the raw data chunk cache.
  INTEGER(SIZE_T), INTENT(IN) :: rdcc_nbytes  ! Total size of the raw data
                                              ! chunk cache in bytes.
  REAL, INTENT(IN) :: rdcc_w0                 ! Preemption policy
  INTEGER, INTENT(OUT) :: hdferr              ! Error code
                                              ! 0 on success and -1 on failure
END SUBROUTINE h5pset_cache_f
        
See Also:
H5Pget_cache
H5Pset_chunk_cache
“Chunking in HDF5”

History:




Last modified: 24 September 2014
Name: H5Pset_char_encoding
Signature:
herr_t H5Pset_char_encoding( hid_t plist_id, H5T_cset_t encoding )

Purpose:
Sets the character encoding used to encode link and attribute names.

Description:
H5Pset_char_encoding sets the character encoding used for the names of links (which provide the names by which objects are referenced) or attributes created with the property list plist_id.

Valid values for encoding include the following:
     H5T_CSET_ASCII US ASCII
     H5T_CSET_UTF8     UTF-8 Unicode

For example, if the character set for the property list plist_id is set to H5T_CSET_UTF8, link names pointing to objects created with the link creation property list plist_id will be encoded using the UTF-8 character set. Similarly, names of attributes created with the attribute creation property list plist_id will be encoded as UTF-8.

ASCII and UTF-8 Unicode are the only currently supported character encodings. Extended ASCII encodings (for example, ISO 8859) are not supported. This encoding policy is not enforced by the HDF5 Library. Using encodings other than ASCII and UTF-8 can lead to compatibility and usability problems.

Note that H5Pset_char_encoding sets the character set used for an HDF5 link or attribute name while H5Tset_cset sets the character set used in a character or string datatype.

Parameters:
hid_t plist_id IN: Link creation or attribute creation property list identifier
H5T_cset_t encoding     IN: String encoding character set

Returns:
Returns a non-negative valule if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_char_encoding_f
SUBROUTINE h5pset_char_encoding_f(plist_id, encoding, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id
                                  ! Property list identifier
  INTEGER, INTENT(IN) :: encoding ! String encoding character set:
                                  !   H5T_CSET_ASCII_F -> US ASCII
                                  !   H5T_CSET_UTF8_F -> UTF-8 Unicode encoding
  INTEGER, INTENT(OUT) :: hdferr  ! Error code
                                  ! 0 on success and -1 on failure
END SUBROUTINE h5pset_char_encoding_f
    
See Also:
“Using UTF-8 Encoding in HDF5 Applications”

History:
Release     C
1.8.0 Function introduced in this release.

Last modified: 16 September 2015

Name: H5Pset_chunk

Signature:
herr_t H5Pset_chunk(hid_t plist, int ndims, const hsize_t * dim )

Purpose:
Sets the size of the chunks used to store a chunked layout dataset.

Description:

H5Pset_chunk sets the size of the chunks used to store a chunked layout dataset. This function is only valid for dataset creation property lists.

The ndims parameter currently must be the same size as the rank of the dataset.

The values of the dim array define the size of the chunks to store the dataset's raw data. The unit of measure for dim values is dataset elements.

As a side-effect of this function, the layout of the dataset is changed to H5D_CHUNKED, if it is not already so set. (See H5Pset_layout.)


Notes:

Parameters:

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_chunk_f
SUBROUTINE h5pset_chunk_f(prp_id, ndims, dims, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier 
  INTEGER, INTENT(IN) :: ndims          ! Number of chunk dimensions
  INTEGER(HSIZE_T), DIMENSION(ndims), INTENT(IN) :: dims    
                                        ! Array containing sizes of
                                        ! chunk dimensions
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pset_chunk_f
	
History:
Release     Change
1.8.16 Added chunk size limit note to Description.


Last modified: 4 November 2014
Name: H5Pset_chunk_cache
Signature:
herr_t H5Pset_chunk_cache( hid_t dapl_id, size_t rdcc_nslots, size_t rdcc_nbytes, double rdcc_w0 )

Purpose:
Sets the raw data chunk cache parameters.

Motivation:
H5Pset_chunk_cache is used to adjust the chunk cache parameters on a per-dataset basis, as opposed to a global setting for the file using H5Pset_cache. The optimum chunk cache parameters may vary widely with different data layout and access patterns, so for optimal performance they must be set individually for each dataset. It may also be beneficial to reduce the size of the chunk cache for datasets whose performance is not important in order to save memory space.

Description:
H5Pset_chunk_cache sets the number of elements, the total number of bytes, and the preemption policy value in the raw data chunk cache on a dataset access property list. After calling this function, the values set in the property list will override the values in the file's file access property list.

The raw data chunk cache inserts chunks into the cache by first computing a hash value using the address of a chunk, then using that hash value as the chunk's index into the table of cached chunks. The size of this hash table, i.e., and the number of possible hash values, is determined by the rdcc_nslots parameter. If a different chunk in the cache has the same hash value, this causes a collision, which reduces efficiency. If inserting the chunk into cache would cause the cache to be too big, then the cache is pruned according to the rdcc_w0 parameter.

Parameters:
hid_t dapl_id      IN: Dataset access property list identifier.
size_t rdcc_nslots   IN:The number of chunk slots in the raw data chunk cache for this dataset. Increasing this value reduces the number of cache collisions, but slightly increases the memory used. Due to the hashing strategy, this value should ideally be a prime number. As a rule of thumb, this value should be at least 10 times the number of chunks that can fit in rdcc_nbytes bytes. For maximum performance, this value should be set approximately 100 times that number of chunks.

The default value is 521. If the value passed is H5D_CHUNK_CACHE_NSLOTS_DEFAULT, then the property will not be set on dapl_id and the parameter will come from the file access property list used to open the file.

size_t rdcc_nbytes   IN: The total size of the raw data chunk cache for this dataset. In most cases increasing this number will improve performance, as long as you have enough free memory.

The default size is 1 MB. If the value passed is H5D_CHUNK_CACHE_NBYTES_DEFAULT, then the property will not be set on dapl_id and the parameter will come from the file access property list.

double rdcc_w0   IN: The chunk preemption policy for this dataset. This must be between 0 and 1 inclusive and indicates the weighting according to which chunks which have been fully read or written are penalized when determining which chunks to flush from cache. A value of 0 means fully read or written chunks are treated no differently than other chunks (the preemption is strictly LRU) while a value of 1 means fully read or written chunks are always preempted before other chunks. If your application only reads or writes data once, this can be safely set to 1. Otherwise, this should be set lower, depending on how often you re-read or re-write the same data.

The default value is 0.75. If the value passed is H5D_CHUNK_CACHE_W0_DEFAULT, then the property will not be set on dapl_id and the parameter will come from the file access property list.


Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Example Usage:
The following code sets the chunk cache to use a hash table with 12421 elements and a maximum size of 16 MB, while using the preemption policy specified for the entire file:
H5Pset_chunk_cache(dapl_id, 12421, 16*1024*1024, H5D_CHUNK_CACHE_W0_DEFAULT);
Usage Notes:
The chunk cache size is a property for accessing a dataset and is not stored with a dataset or a file. To guarantee the same chunk cache settings each time H5Dopen is called, call H5Dopen with a dataset access property list (H5Dopen(hid_t loc_id, const char *name, hid_t dapl_id)) where the chunk cache size is set by calling H5Pset_chunk_cache for that property list. The property list can be used for multiple accesses in the same application.

For files where the same chunk cache size will be appropriate for all or most datasets, H5Pset_cache can be called with a file access property list to set the chunk cache size for accessing all datasets in the file.

Both methods can be used in combination, in which case the chunk cache size set by H5Pset_cache will apply except for specific datasets where H5Dopen is called with dataset property list with the chunk cache size set by H5Pset_chunk_cache.

In the absence of any cache settings, H5Dopen will by default create a 1 MB chunk cache for the opened dataset. If this size happens to be appropriate, no call will be needed to either function to set the chunk cache size.

It is also possible that a change in access pattern for later access to a dataset will change the appropriate chunk cache size. For more detailed information on chunks, chunk caching, and performance pitfalls, see “Chunking in HDF5”.

Fortran90 Interface: h5pset_chunk_cache_f
SUBROUTINE h5pset_chunk_cache_f(dapl_id, rdcc_nslots, rdcc_nbytes, rdcc_w0, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: dapl_id      ! Dataset access property list 
                                             ! identifier.
  INTEGER(SIZE_T), INTENT(IN) :: rdcc_nslots ! The number of chunk slots in the 
                                             ! raw data chunk cache for this 
                                             ! dataset.
  INTEGER(SIZE_T), INTENT(IN) :: rdcc_nbytes ! The total size of the raw data 
                                             ! chunk cache for this dataset.
  REAL, INTENT(IN) :: rdcc_w0                ! The chunk preemption policy for 
                                             ! this dataset.
  INTEGER, INTENT(OUT) :: hdferr             ! Error code
                                             ! 0 on success and -1 on failure
END SUBROUTINE h5pset_chunk_cache_f
    

See Also:
H5Pget_chunk_cache
H5Pset_cache
“Chunking in HDF5”

History:
Release     Change
1.8.3 C function introduced in this release.




Last modified: 3 July 2013
Name: H5Pset_copy_object
Signature:
herr_t H5Pset_copy_object( hid_t ocpypl_id, unsigned copy_options )

Purpose:
Sets properties to be used when an object is copied.

Description:
H5Pset_copy_object sets properties in the object copy property list ocpypl_id. When an existing object is copied, that property list will determine how the new copy is created.

The following flags are available for use in an object copy property list:

Parameters:
hid_t ocpypl_id IN: Object copy property list identifier
unsigned copy_options     IN: Copy option(s) to be set

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
See Also:
H5Ocopy    

Copying Committed Datatypes
    with H5Ocopy
 
A comprehensive discussion of copying committed datatypes (PDF) in Advanced Topics in HDF5

H5Padd_merge_committed_dtype_path
H5Pfree_merge_committed_dtype_paths
H5Pset_mcdt_search_cb
H5Pget_mcdt_search_cb
H5O_mcdt_search_cb_t
 
Functions and a callback function used to tune committed datatype copying behavior

Fortran90 Interface: h5pset_copy_object_f
SUBROUTINE h5pset_copy_object_f(ocpypl_id, copy_options, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: ocpypl_id 
                              ! Object copy property list identifier
  INTEGER, INTENT(IN) :: copy_options 
                              ! Copy option(s) to be set, valid options are:
                              !   H5O_COPY_SHALLOW_HIERARCHY_F
                              !   H5O_COPY_EXPAND_SOFT_LINK_F 
                              !   H5O_COPY_EXPAND_EXT_LINK_F
                              !   H5O_COPY_EXPAND_REFERENCE_F
                              !   H5O_COPY_WITHOUT_ATTR_FLAG_F
                              !   H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG_F
  INTEGER, INTENT(OUT) :: hdferr      
                              ! Error code
                              ! 0 on success and -1 on failure
END SUBROUTINE h5pset_copy_object_f
    

History:
Release     C
1.8.0 Function introduced in this release.
1.8.9 H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG added in this release.

Last modified: 13 August 2014

Name: H5Pset_core_write_tracking

Signature:
herr_t H5Pset_core_write_tracking( hid_t fapl_id, hbool_t is_enabled, size_t page_size )

Purpose:
Sets write tracking information for core driver, H5FD_CORE.

Description:
When a file is created or opened for writing using the core virtual file driver (VFD) with the backing store option turned on, the core driver can be configured to track changes to the file and write out only the modified bytes.

This write tracking feature is enabled and disabled with is_enabled. The default setting is that write tracking is disabled, or off.

To avoid a large number of small writes, changes can be aggregated into pages of a user-specified size, page_size.

Setting page_size to 1 enables tracking with no page aggregation.

The backing store option is set via the function H5Pset_fapl_core.

Notes:
This function is only for use with the core VFD and must be used after the call to H5Pset_fapl_core. It is an error to use this function with any other VFD.

It is an error to use this function when the backing store flag has not been set using H5Pset_fapl_core.

This function only applies to the backing store write operation which typically occurs when the file is flushed or closed. This function has no relationship to the increment parameter passed to H5Pset_fapl_core.

For optimum performance, the page_size parameter should be a power of two.

It is an error to set the page size to 0.

Parameters:
hid_t fapl_id IN: File access property list identifier.
hbool_t is_enabled   IN: Boolean value specifying whether feature is enabled.
size_t page_size IN: Positive integer specifying size, in bytes, of write aggregation pages.
Value of 1 (one) enables tracking with no paging.

Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Fortran Interface:
None

See Also:
H5Pget_core_write_tracking

History:
Release Change
1.8.13 C function introduced with this release.
1.8.14 C function modified in this release to return error if page_size is set to 0 (zero).

Last modified: 11 May 2011
Name: H5Pset_create_intermediate_group
Signature:
herr_t H5Pset_create_intermediate_group( hid_t lcpl_id, unsigned crt_intermed_group )

Purpose:
Specifies in property list whether to create missing intermediate groups.

Description:
H5Pset_create_intermediate_group specifies whether to set the link creation property list lcpl_id so that calls to functions that create objects in groups different from the current working group will create intermediate groups that may be missing in the path of a new or moved object.

Functions that create objects in or move objects to a group other than the current working group make use of this property. H5Gcreate_anon and H5Lmove are examples of such functions.

If crt_intermed_group is positive, the H5G_CRT_INTMD_GROUP will be added to lcpl_id (if it is not already there). Missing intermediate groups will be created upon calls to functions such as those listed above that use lcpl_id.

If crt_intermed_group is non-positive, the H5G_CRT_INTMD_GROUP, if present, will be removed from lcpl_id. Missing intermediate groups will not be created upon calls to functions such as those listed above that use lcpl_id.

Parameters:
hid_t lcpl_id IN: Link creation property list identifier
unsigned crt_intermed_group     IN: Flag specifying whether to create intermediate groups upon the creation of an object

Returns:
Returns a non-negative valule if successful; otherwise returns a negative value.

Example:
The following call sets the link creation property list lcpl_id such that a call to H5Gcreate_anon or other function using lcpl_id will create any missing groups in the path to the new object:
    herr_t ret_value = H5Pset_create_intermediate_group(lcpl_id, 1) 

Fortran90 Interface: h5pset_create_inter_group_f
SUBROUTINE h5pset_create_inter_group_f(lcpl_id, crt_intermed_group, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: lcpl_id 
                           ! Link creation property list identifier
  INTEGER, INTENT(IN) :: crt_intermed_group  
                           ! Specifying whether to create intermediate groups 
                           ! upon the creation of an object
  INTEGER, INTENT(OUT) :: hdferr 
                           ! Error code
                           ! 0 on success and -1 on failure
END SUBROUTINE h5pset_create_inter_group_f
	

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pset_data_transform
Signature:
herr_t H5Pset_data_transform (hid_t plist_id, const char *expression)
Purpose:
Sets a data transform expression.
Description:
H5Pset_data_transform sets the data transform to be used for reading and writing data. This function operates on the dataset transfer property lists plist_id.

The expression parameter is a string containing an algebraic expression, such as (5/9.0)*(x-32) or x*(x-5). When a dataset is read or written with this property list, the transform expression is applied with the x being replaced by the values in the dataset. When reading data, the values in the file are not changed and the transformed data is returned to the user.

Data transforms can only be applied to integer or floating-point datasets. Order of operations is obeyed and the only supported operations are +, -, *, and /. Parentheses can be nested arbitrarily and can be used to change precedence.

When writing data back to the dataset, the transformed data is written to the file and there is no way to recover the original values to which the transform was applied.

Parameters:
Returns:
Success: a non-negative value
Failure: a negative value
Fortran90 Interface: SUBROUTINE h5pset_data_transform_f
SUBROUTINE h5pset_data_transform_f(plist_id, expression, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: plist_id 
                                    ! Identifier of the property list or class
  CHARACTER(LEN=*), INTENT(IN) :: expression  
                                    ! Buffer to hold transform expression
  INTEGER, INTENT(OUT) :: hdferr    ! Error code
                                    ! 0 on success and -1 on failure
END SUBROUTINE h5pset_data_transform_f
    
History:
Release     C
1.8.0 Function introduced in this release.

Last modified: 20 June 2013
Name: H5Pset_deflate
Signature:
herr_t H5Pset_deflate( hid_t plist_id, uint level )

Purpose:
Sets deflate (GNU gzip) compression method and compression level.

Description:
H5Pset_deflate sets the deflate compression method and the compression level, level for a dataset or group creation property list, plist_id.

The filter identifier set in the propertly list is H5Z_FILTER_DEFLATE.

The compression level, level, is a value from zero to nine, inclusive. A compression level of 0 (zero) indicates no compression; compression improves but speed slows progressively from levels 1 through 9:

  Compression level          Gzip action
  0   No compression
  1   Best compression speed; least compression
  2 through 8   Compression improves; speed degrades
  9   Best compression ratio; slowest speed

Note that setting the compression level to 0 (zero) does not turn off use of the gzip filter; it simply sets the filter to perform no compression as it processes the data.

HDF5 relies on GNU gzip for this compression (see zlib).

Parameters:
hid_t plist_id     IN: Dataset or group creation property list identifier.
uint level IN: Compression level.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_deflate_f
SUBROUTINE h5pset_deflate_f(prp_id, level, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id ! Property list identifier 
  INTEGER, INTENT(IN)        :: level  ! Compression level 
  INTEGER, INTENT(OUT)       :: hdferr ! Error code
                                       ! 0 on success and -1 on failure
END SUBROUTINE h5pset_deflate_f
        

History:
Release     Change
1.8.5 Function extended to work with group creation property lists.

Name: H5Pset_driver
Signature:
herr_t H5Pset_driver( hid_t plist_id, hid_t new_driver_id, const void *new_driver_info )

Purpose:
Sets a file driver.

Description:
H5Pset_driver sets the file driver, new_driver_id, for a file access or data transfer property list, plist_id, and supplies an optional struct containing the driver-specific properties, new_driver_info.

The driver properties will be copied into the property list and the reference count on the driver will be incremented, allowing the caller to close the driver identifier but still use the property list.

Note:
H5Pset_driver and H5Pget_driver_info are used only when creating a virtual file driver (VFD) in the virtual file layer (VFL). For further information, see “Virtual File Layer” and “List of VFL Functions” in the HDF5 Technical Notes.

Parameters:
hid_t plist_id
IN: File access or data transfer property list identifier.
hid_t new_driver_id
IN: Driver identifier.
const void * new_driver_info
IN: Optional struct containing driver properties.

Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Fortran90 Interface:
None.

History:

Name: H5Pset_dxpl_mpio
Signature:
herr_t H5Pset_dxpl_mpio( hid_t dxpl_id, H5FD_mpio_xfer_t xfer_mode )
Purpose:
Sets data transfer mode.
Description:
H5Pset_dxpl_mpio sets the data transfer property list dxpl_id to use transfer mode xfer_mode. The property list can then be used to control the I/O transfer mode during data I/O operations.

Valid transfer modes are as follows:

H5FD_MPIO_INDEPENDENT
Use independent I/O access (default).
H5FD_MPIO_COLLECTIVE
Use collective I/O access.

Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Fortran90 Interface:
SUBROUTINE h5pset_dxpl_mpio_f(prp_id, data_xfer_mode, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier
  INTEGER, INTENT(IN) :: data_xfer_mode ! Data transfer mode 
                                        ! Possible values are:
                                        !    H5FD_MPIO_INDEPENDENT_F
                                        !    H5FD_MPIO_COLLECTIVE_F
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pset_dxpl_mpio_f
	
History:

Name: H5Pset_dxpl_mpio_chunk_opt
Signature:
herr_t H5Pset_dxpl_mpio_chunk_opt (hid_t dxpl_id, H5FD_mpio_chunk_opt_t opt_mode)
Purpose:
Sets a flag specifying linked-chunk I/O or multi-chunk I/O.
Description:
H5Pset_dxpl_mpio_chunk_opt specifies whether I/O is to be performed as linked-chunk I/O or as multi-chunk I/O. This function overrides the HDF5 Library's internal algorithm for determining which mechanism to use.

When an application uses collective I/O with chunked storage, the HDF5 Library normally uses an internal algorithm to determine whether that I/O activity should be conducted as one linked-chunk I/O or as multi-chunk I/O. H5Pset_dxpl_mpio_chunk_opt is provided so that an application can override the library's alogorithm in circumstances where the library might lack the information needed to make an optimal desision.

H5Pset_dxpl_mpio_chunk_opt works by setting one of the following flags in the parameter opt_mode:

This function works by setting a corresponding property in the dataset transfer property list dxpl_id.

The library perform I/O in the specified manner unless it determines that the low-level MPI IO package does not support the requested behavior; in such cases, the HDF5 Library will internally use independent I/O.

Use of this function is optional.

Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Name: H5Pset_dxpl_mpio_chunk_opt_num
Signature:
herr_t H5Pset_dxpl_mpio_chunk_opt_num (hid_t dxpl_id, unsigned num_chunk_per_proc)
Purpose:
Sets a numeric threshold for linked-chunk I/O.
Description:
H5Pset_dxpl_mpio_chunk_opt_num sets a numeric threshold for the use of linked-chunk I/O.

The library will calculate the average number of chunks selected by each process when doing collective access with chunked storage. If the number is greater than the threshold set in num_chunk_per_proc, the library will use linked-chunk I/O; otherwise, a separate I/O process will be invoked for each chunk (multi-chunk I/O).

Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Name: H5Pset_dxpl_mpio_chunk_opt_ratio
Signature:
herr_t H5Pset_dxpl_mpio_chunk_opt_ratio (hid_t dxpl_id, unsigned percent_proc_per_chunk)
Purpose:
Sets a ratio threshold for collective I/O.
Description:
H5Pset_dxpl_mpio_chunk_opt_ratio sets a threshold for the use of collective I/O based on the ratio of processes with collective access to a dataset with chunked storage. The decision whether to use collective I/O is made on a per-chunk basis.

The library will calculate the percentage of the total number of processes, the ratio, that hold selections in each chunk. If that percentage is greater than the threshold set in percent_proc_per_chunk, the library will do collective I/O for this chunk; otherwise, independent I/O will be done for the chunk.

Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Name: H5Pset_dxpl_mpio_collective_opt
Signature:
herr_t H5Pset_dxpl_mpio_collective_opt (hid_t dxpl_id, H5FD_mpio_collective_opt_t opt_mode)
Purpose:
Sets a flag governing the use of independent versus collective I/O.
Description:
H5Pset_dxpl_mpio_collective_opt enables an application to specify that the HDF5 Library will use independent I/O internally when the dataset transfer property list dxpl_id is set for collective I/O, i.e., with H5FD_MPIO_COLLECTIVE specified. This allows the application greater control over low-level I/O while maintaining the collective interface at the application level.

H5Pset_dxpl_mpio_collective_opt works by setting one of the following flags in the parameter opt_mode:

This function should be used only when H5FD_MPIO_COLLECTIVE has been set through H5Pset_dxpl_mpio. In such situations, normal behavior would be to use low-level collective I/O functions, but the library will use low-level MPI independent I/O functions when H5FD_MPIO_INDIVIDUAL_IO is set.

Use of this function is optional.

Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Last modified: 20 May 2010
Name: H5Pset_edc_check
Signature:
herr_t H5Pset_edc_check( hid_t plist, H5Z_EDC_t check )

Purpose:
Sets whether to enable error-detection when reading a dataset.

Description:
H5Pset_edc_check sets the dataset transfer property list plist to enable or disable error detection when reading data.

Whether error detection is enabled or disabled is specified in the check parameter. Valid values are as follows:
       H5Z_ENABLE_EDC   (default)
H5Z_DISABLE_EDC

The error detection algorithm used is the algorithm previously specified in the corresponding dataset creation property list.  

This function does not affect the use of error detection when writing data.  

Note:
The initial error detection implementation, Fletcher32 checksum, supports error detection for chunked datasets only.

Note:
The Fletcher32 EDC checksum filter, set with H5Pset_fletcher32, was added in HDF5 Release 1.6.0. In the original implementation, however, the checksum value was calculated incorrectly on little-endian systems. The error was fixed in HDF5 Release 1.6.3.

As a result of this fix, an HDF5 Library of Release 1.6.0 through Release 1.6.2 cannot read a dataset created or written with Release 1.6.3 or later if the dataset was created with the checksum filter and the filter is enabled in the reading library. (Libraries of Release 1.6.3 and later understand the earlier error and comensate appropriately.)

Work-around: An HDF5 Library of Release 1.6.2 or earlier will be able to read a dataset created or written with the checksum filter by an HDF5 Library of Release 1.6.3 or later if the checksum filter is disabled for the read operation. This can be accomplished via an H5Pset_edc_check call with the value H5Z_DISABLE_EDC in the second parameter. This has the obvious drawback that the application will be unable to verify the checksum, but the data does remain accessible.

Parameters:

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_edc_check_f
SUBROUTINE h5pset_edc_check_f(prp_id, flag, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id   ! Dataset transfer property 
                                         ! list identifier 
  INTEGER, INTENT(IN)        :: flag     ! EDC flag; possible values
                                         !    H5Z_DISABLE_EDC_F 
                                         !    H5Z_ENABLE_EDC_F 
  INTEGER, INTENT(OUT)       :: hdferr   ! Error code
                                         ! 0 on success and -1 on failure
 
END SUBROUTINE h5pset_edc_check_f
    

History:

Last modified: 26 April 2016

Name: H5Pset_efile_prefix

Signature:
herr_t H5Pset_efile_prefix( hid_t dapl_id, const char *prefix )

Purpose:
Sets the external dataset storage file prefix in the dataset access property list.

Description:
H5Pset_efile_prefix sets the prefix used to locate raw data files for a dataset that uses external storage. This prefix can provide either an absolute path or a relative path to the external files.

H5Pset_efile_prefix is used in conjunction with H5Pset_external to control the behavior of the HDF5 Library when searching for the raw data files associated with a dataset that uses external storage:

The HDF5_EXTFILE_PREFIX environment variable can be used to override the above behavior (the environment variable supersedes the API call). Setting the variable to a path string and calling H5Dcreate or H5Dopen is the equivalent of calling H5Pset_efile_prefix and calling the same create or open function. The environment variable is checked at the time of the create or open action and copied so it can be safely changed after the H5Dcreate or H5Dopen call.

Calling H5Pset_efile_prefix with prefix set to NULL or the empty string returns the search path to the default. The result would be the same as if H5Pset_efile_prefix had never been called.


Notes:
If the external file prefix is not an absolute path and the HDF5 file is moved, the external storage files will also need to be moved so they can be accessed at the new location.

As stated above, the use of the HDF5_EXTFILE_PREFIX environment variable overrides any property list setting. H5Pset_efile_prefix and H5Pget_efile_prefix, being property functions, set and retrieve only the property list setting; they are unaware of the environment variable.

On Windows, the prefix must be an ASCII string since the Windows standard C library’s I/O functions cannot handle UTF-8 file names.


Parameters:
hid_t dapl_id   IN: Dataset access property list identifier
const char *prefix   IN: Dataset external storage prefix in UTF-8 or ASCII
(Path and filename must be ASCII on Windows systems.)

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran Interface:
None

See Also:

History:
Release     Change
1.10.0 and 1.8.17    C function introduced in these releases.




Last modified: 8 May 2009
Name: H5Pset_elink_acc_flags
Signature:
herr_t H5Pset_elink_acc_flags( hid_t lapl_id, unsigned flags )

Purpose:
Sets the external link traversal file access flag in a link access property list.

Motivation:
H5Pset_elink_acc_flags is used to adjust the file access flag used to open files reached through external links. This may be useful to, for example, prevent modifying files accessed through an external link. Otherwise, the target file is opened with whatever flag was used to open the parent.

Description:
H5Pset_elink_acc_flags specifies the file access flag to use to open the target file of an external link. This allows read-only access of files reached through an external link in a file opened with write access, or vice-versa.

The library will normally use the file access flag used to open the parent file as the file access flag for the target file. This function provides a way to override that behaviour. The external link traversal callback function set by H5Pset_elink_cb can override the setting from H5Pset_elink_acc_flags.

Parameters:
hid_t lapl_id      IN: Link access property list identifier
unsigned flags   IN: The access flag for external link traversal.

Valid values include:
  H5F_ACC_RDWR   Causes files opened through external links to be opened with write access.
  H5F_ACC_RDONLY   Causes files opened through external links to be opened with read-only access.
  H5F_ACC_DEFAULT   Removes any external link file access flag setting from lapl_id, causing the file access flag setting to be taken from the parent file.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Example Usage:
The following code sets the link access property list lapl_id to open external link target files with read-only access:
status = H5Pset_elink_acc_flags(lapl_id, H5F_ACC_RDONLY);

See Also:
H5Pget_elink_acc_flags,   H5Pset_elink_cb,   H5Fopen,   H5Lcreate_external

History:
Release     Change
1.8.3 C function introduced in this release.

Last modified: 18 June 2013
Name: H5Pset_elink_cb
Signature:
herr_t H5Pset_elink_cb( hid_t lapl_id, H5L_elink_traverse_t func, void *op_data )

Purpose:
Sets the external link traversal callback function in a link access property list.

Motivation:
H5Pset_elink_cb is used to specify a callback function that is executed by the HDF5 Library when traversing an external link. This provides a mechanism to set specific access permissions, modify the file access property list, modify the parent or target file, or take any other user-defined action. This callback function is used in situations where the HDF5 Library's default behavior is not suitable.

Description:
H5Pset_elink_cb sets a user-defined external link traversal callback function in the link access property list lapl_id. The callback function func must conform to the prototype specified in H5L_elink_traverse_t.

The callback function may adjust the file access property list and file access flags to use when opening a file through an external link. The callback will be executed by the HDF5 Library immediately before opening the target file.

The callback will be made after the file access property list set by H5Pset_elink_fapl and the file access flag set by H5Pset_elink_acc_flags are applied, so changes made by this callback function will take precedence.

Programming Note for C++ Developers Using C Functions:

If a C routine that takes a function pointer as an argument is called from within C++ code, the C routine should be returned from normally.

Examples of this kind of routine include callbacks such as H5Pset_elink_cb and H5Pset_type_conv_cb and functions such as H5Tconvert and H5Ewalk2.

Exiting the routine in its normal fashion allows the HDF5 C Library to clean up its work properly. In other words, if the C++ application jumps out of the routine back to the C++ “catch” statement, the library is not given the opportunity to close any temporary data structures that were set up when the routine was called. The C++ application should save some state as the routine is started so that any problem that occurs might be diagnosed.

Note:
A file close degree property setting (H5Pset_fclose_degree) in this callback function or an associated property list will be ignored. A file opened by means of traversing an external link is always opened with the weak file close degree property setting, H5F_CLOSE_WEAK.

Parameters:
hid_t lapl_id      IN: Link access property list identifier.
H5L_elink_traverse_t func   IN: User-defined external link traversal callback function.
void *op_data   IN: User-defined input data for the callback function.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Failure Modes:
H5Pset_elink_cb will fail if the link access property list identifier, lapl_id, is invalid or if the function pointer, func, is NULL.

An invalid function pointer, func, will cause a segmentation fault or other failure when an attempt is subsequently made to traverse an external link.

Example Usage:
This example defines a callback function that prints the name of the target file every time an external link is followed, and sets this callback function on lapl_id
herr_t elink_callback(const char *parent_file_name, const char
        *parent_group_name, const char *child_file_name, const char
        *child_object_name, unsigned *acc_flags, hid_t fapl_id, void *op_data) {
    puts(child_file_name);
    return 0;
}

int main(void) {
    hid_t lapl_id = H5Pcreate(H5P_LINK_ACCESS);
    H5Pset_elink_cb(lapl_id, elink_callback, NULL);
    ...
}

See Also:
H5Pget_elink_cb

H5Pset_elink_fapl,   H5Pset_elink_acc_flags,   H5Lcreate_external

H5Fopen for discussion of H5F_ACC_RDWR and H5F_ACC_RDONLY file access flags

H5L_elink_traverse_t

History:
Release     Change
1.8.3 C function introduced in this release.

Last modified: 18 June 2013
Name: H5Pset_elink_fapl
Signature:
herr_t H5Pset_elink_fapl( hid_t lapl_id, hid_t fapl_id )

Purpose:
Sets a file access property list for use in accessing a file pointed to by an external link.

Description:
H5Pset_elink_fapl sets the file access property list, fapl_id, to be used when accessing the target file of an external link associated with lapl_id.

Note:
A file close degree property setting (H5Pset_fclose_degree) in this property list will be ignored. A file opened by means of traversing an external link is always opened with the weak file close degree property setting, H5F_CLOSE_WEAK.

Parameters:
hid_t lapl_id      IN: Link access property list identifier
hid_t fapl_id   IN: File access property list identifier

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

See Also:
H5Pget_elink_fapl
H5Lcreate_external

Fortran90 Interface:
None.

History:
Release     Change
1.9.0 C function introduced in this release.

Last modified: 11 May 2011
Name: H5Pset_elink_file_cache_size
Signature:
herr_t H5Pset_elink_file_cache_size( hid_t fapl_id, unsigned efc_size )

Purpose:
Sets the number of files that can be held open in an external link open file cache.

Motivation:
The external link open file cache holds files open after they have been accessed via an external link. This cache reduces the number of times such files are opened when external links are accessed repeatedly and can siginificantly improves performance in certain heavy-use situations and when low-level file opens or closes are expensive.

H5Pset_elink_file_cache_size sets the number of files that will be held open in an external link open file cache; H5Pget_elink_file_cache_size retrieves the size of an existing cache; and H5Fclear_elink_file_cache clears an existing cache without closing it.

Description:
H5Pset_elink_file_cache_size specifies the number of files that will be held open in an external link open file cache.

The default external link open file cache size is 0 (zero), meaning that files accessed via an external link are not held open. Setting the cache size to a positive integer turns on the cache; setting the size back to zero turns it off.

With this property set, files are placed in the external link open file cache cache when they are opened via an external link. Files are then held open until either they are evicted from the cache or the parent file is closed. This property setting can improve performance when external links are repeatedly accessed.

When the cache is full, files will be evicted using a least recently used (LRU) scheme; the file which has gone the longest time without being accessed through the parent file will be evicted and closed if nothing else is holding that file open.

Files opened through external links inherit the parent file’s file access property list by default, and therefore inherit the parent file’s external link open file cache setting.

When child files contain external links of their own, the caches can form a graph of cached external files. Closing the last external reference to such a graph will recursively close all files in the graph, even if cycles are present.

Parameters:
hid_t fapl_id      IN: File access property list identifier
unsigned efc_size   IN: External link open file cache size in number of files.
Default setting is 0 (zero).

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Example Usage:
The following code sets up an external link open file cache that will hold open up to 8 files reached through external links:
    status = H5Pset_elink_file_cache_size(fapl_id, 8);        

See Also:
H5Pget_elink_file_cache_size
H5Fclear_elink_file_cache
H5Lcreate_external
H5Pset_elink_fapl

History:
Release     Change
1.8.7 C function introduced in this release.

Name: H5Pset_elink_prefix
Signature:
herr_t H5Pset_elink_prefix( hid_t lapl_id, const char *prefix )

Purpose:
Sets prefix to be applied to external link paths.

Description:
H5Pset_elink_prefix sets the prefix to be applied to the path of any external links traversed. The prefix is prepended to the filename stored in the external link.

The prefix is specified in the user-allocated buffer prefix and set in the link access property list lapl_id. The buffer should not be freed until the property list has been closed.

Parameters:
hid_t lapl_id IN: Link access property list identifier
const char *prefix     IN: Prefix to be applied to external link paths

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pset_est_link_info
Signature:
herr_t H5Pset_est_link_info( hid_t gcpl_id, unsigned est_num_entries, unsigned est_name_len )

Purpose:
Sets estimated number of links and length of link names in a group.

Description:
H5Pset_est_link_info inserts two settings into the group creation property list gcpl_id: the estimated number of links that are expected to be inserted into a group created with the property list and the estimated average length of those link names.

The estimated number of links is passed in est_num_entries.

The estimated average length of the anticipated link names is passed in est_name_len.

The values for these two settings are multiplied to compute the initial local heap size (for old-style groups, if the local heap size hint is not set) or the initial object header size for (new-style compact groups; see “Group implementations in HDF5”). Accurately setting these parameters will help reduce wasted file space.

If a group is expected to have many links and to be stored in dense format, set est_num_entries to 0 (zero) for maximum efficiency. This will prevent the group from being created in the compact format.

See “Group implementations in HDF5” in the H5G API introduction for a discussion of the available types of HDF5 group structures.

Parameters:
hid_t gcpl_id IN: Group creation property list identifier
unsigned est_num_entries     IN: Estimated number of links to be inserted into group
unsigned est_name_len IN: Estimated average length of link names
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
SUBROUTINE H5Pset_est_link_info_f(gcpl_id, est_num_entries, est_name_len, &
                                  hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: gcpl_id 
                                    ! Group creation property list identifier
  INTEGER, INTENT(IN) :: est_num_entries 
                                    ! Estimated number of links to be 
                                    ! inserted into group
  INTEGER, INTENT(IN) :: est_name_len    
                                    ! Estimated average length of link names
  INTEGER, INTENT(OUT) :: hdferr    ! Error code
                                    ! 0 on success and -1 on failure
END SUBROUTINE H5Pset_est_link_info_f
    

History:
Release     C
1.8.0 Function introduced in this release.

Last modified: 22 April 2011
Name: H5Pset_external
Signature:
herr_t H5Pset_external(hid_t plist, const char *name, off_t offset, hsize_t size )

Purpose:
Adds an external file to the list of external files.

Description:
The first call to H5Pset_external sets the external storage property in the property list, thus designating that the dataset will be stored in one or more non-HDF5 file(s) external to the HDF5 file. This call also adds the file name as the first file in the list of external files. Subsequent calls to the function add the named file as the next file in the list.

If a dataset is split across multiple files, then the files should be defined in order. The total size of the dataset is the sum of the size arguments for all the external files. If the total size is larger than the size of a dataset then the dataset can be extended (provided the data space also allows the extending).

The size argument specifies the number of bytes reserved for data in the external file. If size is set to H5F_UNLIMITED, the external file can be of unlimited size and no more files can be added to the external files list. If size is set to 0 (zero), no external file will actually be created.

All of the external files for a given dataset must be specified with H5Pset_external before H5Dcreate is called to create the dataset. If one these files does not exist on the system when H5Dwrite is called to write data to it, the library will create the file.

Parameters:
hid_t plist IN: Identifier of a dataset creation property list.
const char *name     IN: Name of an external file.
off_t offset IN: Offset, in bytes, from the beginning of the file to the location in the file where the data starts.
hsize_t size IN: Number of bytes reserved in the file for the data.

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_external_f
SUBROUTINE h5pset_external_f(prp_id, name, offset,bytes, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier
  CHARACTER(LEN=*), INTENT(IN) :: name  ! Name of an external file
  INTEGER, INTENT(IN) :: offset         ! Offset, in bytes, from the 
                                        ! beginning of the file to the 
                                        ! location in the file where 
                                        ! the data starts
  INTEGER(HSIZE_T), INTENT(IN) :: bytes ! Number of bytes reserved in 
                                        ! the file for the data
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pset_external_f
    

Name: H5Pset_family_offset
Signature:
herr_t H5Pset_family_offset ( hid_t fapl_id, hsize_t offset )
Purpose:
Sets offset property for low-level access to a file in a family of files.
Description:
H5Pset_family_offset sets the offset property in the file access property list fapl_id so that the user application can retrieve a file handle for low-level access to a particular member of a family of files. The file handle is retrieved with a separate call to H5Fget_vfd_handle (or, in special circumstances, to H5FDget_vfd_handle; see Virtual File Layer and List of VFL Functions in HDF5 Technical Notes).

The value of offset is an offset in bytes from the beginning of the HDF5 file, identifying a user-determined location within the HDF5 file. The file handle the user application is seeking is for the specific member-file in the associated family of files to which this offset is mapped.

Use of this function is only appropriate for an HDF5 file written as a family of files with the FAMILY file driver.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pset_family_offset_f
SUBROUTINE h5pset_family_offset_f(prp_id, offset, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN)   :: prp_id   ! Property list identifier
  INTEGER(HSIZE_T), INTENT(IN) :: offset   ! Offset in bytes
  INTEGER, INTENT(OUT)         :: hdferr   ! Error code
                                           ! 0 on success and -1 on failure
 
END SUBROUTINE h5pset_family_offset_f
	
History:

Name: H5Pset_fapl_core
Signature:
herr_t H5Pset_fapl_core( hid_t fapl_id, size_t increment, hbool_t backing_store )
Purpose:
Modifies the file access property list to use the H5FD_CORE driver.
Description:
H5Pset_fapl_core modifies the file access property list to use the H5FD_CORE driver.

The H5FD_CORE driver enables an application to work with a file in memory, speeding reads and writes as no disk access is made. File contents are stored only in memory until the file is closed. The backing_store parameter determines whether file contents are ever written to disk.

increment specifies the increment by which allocated memory is to be increased each time more memory is required.

While using H5Fcreate to create a core file, if the backing_store is set to 1 (TRUE), the file contents are flushed to a file with the same name as this core file when the file is closed or access to the file is terminated in memory.

The application is allowed to open an existing file with H5FD_CORE driver. While using H5Fopen to open an existing file, if the backing_store is set to 1 and the flags for H5Fopen is set to H5F_ACC_RDWR, any change to the file contents are saved to the file when the file is closed. If backing_store is set to 0 and the flags for H5Fopen is set to H5F_ACC_RDWR, any change to the file contents will be lost when the file is closed. If the flags for H5Fopen is set to H5F_ACC_RDONLY, no change to the file is allowed either in memory or on file.

Note:
Currently this driver cannot create or open family or multi files.
Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Fortran90 Interface: h5pset_fapl_core_f
SUBROUTINE h5pset_fapl_core_f(prp_id, increment, backing_store, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN)  :: prp_id    ! Property list identifier
  INTEGER(SIZE_T), INTENT(IN) :: increment ! File block size in bytes
  LOGICAL, INTENT(IN) :: backing_store     ! Flag to indicate that entire 
                                           ! file contents are flushed to 
                                           ! a file with the same name as 
                                           ! this core file
  INTEGER, INTENT(OUT) :: hdferr           ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pset_fapl_core_f
	
History:

Name: H5Pset_fapl_direct
Signature:
herr_t H5Pset_fapl_direct( hid_t fapl_id, size_t alignment, size_t block_size, size_t cbuf_size )

Purpose:
Sets up use of the direct I/O driver.

Description:
H5Pset_fapl_direct sets the file access property list, fapl_id, to use the direct I/O driver, H5FD_DIRECT. With this driver, data is written to or read from the file synchronously without being cached by the system.

File systems usually require the data address in memory, the file address, and the size of the data to be aligned. The HDF5 Library’s direct I/O driver is able to handle unaligned data, though that will consume some additional memory resources and may slow performance. To get better performance, use the system function posix_memalign to align the data buffer in memory and the HDF5 function H5Pset_alignment to align the data in the file. Be aware, however, that aligned data I/O may cause the HDF5 file to be bigger than the actual data size would otherwise require because the alignment may leave some holes in the file.

alignment specifies the required alignment boundary in memory.

block_size specifies the file system block size. A value of 0 (zero) means to use HDF5 Library’s default value of 4KB.

cbuf_size specifies the copy buffer size.

Note:
On an SGI Altix Linux 2.6 system, the memory alignment must be a multiple of 512 bytes, and the file system block size is 4KB. The maximum size for the copy buffer has to be a multiple of the file system block size. The HDF5 Library’s default maximum copy buffer size is 16MB. This copy buffer is used by the library’s internal algorithm to copy data in fragments between an application’s unaligned buffer and the file. The buffer’s size may affect I/O performance.

Parameters:
hid_t fapl_id IN: File access property list identifier
size_t alignment IN: Required memory alignment boundary
size_t block_size     IN: File system block size
size_t cbuf_size IN: Copy buffer size

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface: h5pset_fapl_direct_f
SUBROUTINE h5pset_fapl_direct_f(fapl_id, alignment, block_size, cbuf_size, &
                                hdferr)
  IMPLICIT NONE  
  INTEGER(HID_T), INTENT(IN) :: fapl_id ! File access property list identifier
  INTEGER(SIZE_T), INTENT(IN) :: alignment 	  
                                        ! Required memory alignment boundary
  INTEGER(SIZE_T), INTENT(IN) :: block_size     
                                        ! File system block size
  INTEGER(SIZE_T), INTENT(IN) :: cbuf_size 	  
                                        ! Copy buffer size
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE H5Pset_fapl_direct_f 
    

History:
Release     C
1.8.0 Function introduced in this release.

Name: H5Pset_fapl_family
Signature:
herr_t H5Pset_fapl_family ( hid_t fapl_id, hsize_t memb_size, hid_t memb_fapl_id )
Purpose:
Sets the file access property list to use the family driver.
Description:
H5Pset_fapl_family sets the file access property list identifier, fapl_id, to use the family driver.

memb_size is the size in bytes of each file member. This size will be saved in file when the property list fapl_id is used to create a new file. If fapl_id is used to open an existing file, memb_size has to be equal to the original size saved in file. A failure with an error message indicating the correct member size will be returned if memb_size does not match the size saved. If any user does not know the original size, H5F_FAMILY_DEFAULT can be passed in. The library will retrieve the saved size.

memb_fapl_id is the identifier of the file access property list to be used for each family member.

Parameters:
Returns:
Returns a non-negative value if successful; otherwise returns a negative value.
Fortran90 Interface: h5pset_fapl_family_f
SUBROUTINE h5pset_fapl_family_f(prp_id, imemb_size, memb_plist, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN)   :: prp_id    ! Property list identifier
  INTEGER(HSIZE_T), INTENT(IN) :: memb_size ! Logical size, in bytes,
                                            ! of each family member
  INTEGER(HID_T), INTENT(IN) :: memb_plist  ! Identifier of the file 
                                            ! access property list to be
                                            ! used for each family member
  INTEGER, INTENT(OUT) :: hdferr            ! Error code
                                            ! 0 on success and -1 on failure
END SUBROUTINE h5pset_fapl_family_f
	
History:

Last modified: 12 May 2011
Name: H5Pset_fapl_log
Signature:
herr_t H5Pset_fapl_log( hid_t fapl_id, const char *logfile, unsigned long long flags, size_t buf_size )

Purpose:
Sets up the logging virtual file driver (H5FD_LOG) for use.

Description:
H5Pset_fapl_log modifies the file access property list to use the logging driver, H5FD_LOG. The logging virtual file driver (VFD) is a clone of the standard SEC2 (H5FD_SEC2) driver with additional facilities for logging VFD metrics and activity to a file.

logfile is the name of the file in which the logging entries are to be recorded.

The actions to be logged are specified in the parameter flags using the pre-defined constants described in the following table. Multiple flags can be set through the use of a logical OR contained in parentheses. For example, logging read and write locations would be specified as (H5FD_LOG_LOC_READ|H5FD_LOG_LOC_WRITE).

 
Table 1:   Logging flags
 
Flag Description
H5FD_LOG_LOC_READ Track the location and length of every read, write, or seek operation.
H5FD_LOG_LOC_WRITE  
H5FD_LOG_LOC_SEEK
H5FD_LOG_LOC_IO Track all I/O locations and lengths. The logical equivalent of the following:
  (H5FD_LOG_LOC_READ | H5FD_LOG_LOC_WRITE | H5FD_LOG_LOC_SEEK)
H5FD_LOG_FILE_READ Track the number of times each byte is read or written.
H5FD_LOG_FILE_WRITE  
H5FD_LOG_FILE_IO Track the number of times each byte is read and written. The logical equivalent of the following:
  (H5FD_LOG_FILE_READ | H5FD_LOG_FILE_WRITE)
H5FD_LOG_FLAVOR Track the type, or flavor, of information stored at each byte.
H5FD_LOG_NUM_READ Track the total number of read, write, seek, or truncate operations that occur.
H5FD_LOG_NUM_WRITE
H5FD_LOG_NUM_SEEK
H5FD_LOG_NUM_TRUNCATE  
H5FD_LOG_NUM_IO Track the total number of all types of I/O operations. The logical equivalent of the following:
  (H5FD_LOG_NUM_READ | H5FD_LOG_NUM_WRITE | H5FD_LOG_NUM_SEEK | H5FD_LOG_NUM_TRUNCATE)
H5FD_LOG_TIME_OPEN Track the time spent in open, stat, read, write, seek, or close operations.
H5FD_LOG_TIME_STAT
H5FD_LOG_TIME_READ
H5FD_LOG_TIME_WRITE
H5FD_LOG_TIME_SEEK
H5FD_LOG_TIME_CLOSE  
H5FD_LOG_TIME_IO Track the time spent in each of the above operations. The logical equivalent of the following:
  (H5FD_LOG_TIME_OPEN | H5FD_LOG_TIME_STAT | H5FD_LOG_TIME_READ | H5FD_LOG_TIME_WRITE | H5FD_LOG_TIME_SEEK | H5FD_LOG_TIME_CLOSE)
H5FD_LOG_ALLOC Track the allocation of space in the file.
H5FD_LOG_ALL Track everything. The logical equivalent of the following:
  (H5FD_LOG_ALLOC | H5FD_LOG_TIME_IO | H5FD_LOG_NUM_IO | H5FD_LOG_FLAVOR | H5FD_LOG_FILE_IO | H5FD_LOG_LOC_IO)
 

The logging driver can track the number of times each byte in the file is read from or written to (using H5FD_LOG_FILE_READ and H5FD_LOG_FILE_WRITE) and what kind of data is at that location (e.g., metadata, raw data; using H5FD_LOG_FLAVOR). This information is tracked in internal buffers of size buf_size, which must be at least the maximum size in bytes of the file to be logged while the log driver is in use.

One buffer of size buf_size will be created for each of H5FD_LOG_FILE_READ, H5FD_LOG_FILE_WRITE and H5FD_LOG_FLAVOR when those flags are set; these buffers will not grow as the file increases in size.

Parameters:
hid_t fapl_id IN: File access property list identifier.
char *logfile IN: Name of the log file.
unsigned long long flags     IN: Flags specifying the types of logging activity.
size_t buf_size IN: The size of the logging buffers, in bytes (see description).

Output:
This section describes the logging driver (LOG VFD) output.

The table, immediately below, describes output of the various logging driver flags and function calls; error output is in red italic. A list of valid flavor values, describing the type of data stored, follows the table.

 
Table 2:   Logging output
 
Flag (H5FD_LOG_) VFD Call Output and Comments
LOC_READ Read() %10a-%10a (%10Zu bytes) (%s) Read

Start position
End position
Number of bytes
Flavor of read

Adds (%f s) and seek time if TIME_SEEK is also set.

LOC_READ Read() Error Error! Reading: %10a-%10a (%10Zu bytes)

Same parameters as non-error entry.

LOC_WRITE Write() %10a-%10a (%10Zu bytes) (%s) Written

Start position
End position
Number of bytes
Flavor of write

Adds (%f s) and seek time if TIME_SEEK is also set.

LOC_WRITE Write() Error Error! Writing: %10a-%10a (%10Zu bytes)

Same parameters as non-error entry.

LOC_SEEK Read()
Write()
Seek: From %10a-%10a

Start position
End position

Adds (%f s) and seek time if TIME_SEEK is also set.

FILE_READ Close() Begins with:
Dumping read I/O information

Then, for each range of identical values, there is this line:
\tAddr %10-%10 (%10lu bytes) read from %3d times

Start address
End address
Number of bytes
Number of times read

Note: The data buffer is scanned and each range of identical values gets one entry in the log file to save space and make it easier to read.

FILE_WRITE Close() Begins with:
Dumping write I/O information

Then, for each range of identical values, there is this line:
\tAddr %10-%10 (%10lu bytes) written to %3d times

Start address
End address
Number of bytes
Number of times written

Note: The data buffer is scanned and each range of identical values gets one entry in the log file to save space and make it easier to read.

FLAVOR Close() Begins with:
Dumping I/O flavor information

Then, for each range of identical values, there is this line:
\tAddr %10-%10 (%10lu bytes) flavor is %s

Start address
End address
Number of bytes
Flavor

Note: The data buffer is scanned and each range of identical values gets one entry in the log file to save space and make it easier to read.

NUM_READ Close() Total number of read operations: %11u
NUM_WRITE Close() Total number of write operations: %11u
NUM_SEEK Close() Total number of seek operations: %11u
NUM_TRUNCATE Close() Total number of truncate operations: %11u
TIME_OPEN Open() Open took: (%f s)
TIME_READ Close()
Read()
Total time in read operations: %f s

See also:   LOC_READ

TIME_WRITE Close()
Write()
Total time in write operations: %f s

See also:   LOC_WRITE

TIME_SEEK Close()
Read()
Write()
Total time in seek operations: %f s

See also:   LOC_SEEK  or  LOC_WRITE

TIME_CLOSE Close() Close took: (%f s)
TIME_STAT Open() Stat took: (%f s)
ALLOC Alloc() %10-%10 (%10Hu bytes) (%s) Allocated

Start of address space
End of address space
Total size of allocation
Flavor of allocation

 

Flavors:
The flavor describes the type of stored information. The following table lists the flavors that appear in log output and briefly describes each. These terms are provided here to aid in the construction of log message parsers; a full description is beyond the scope of this document.

 
Table 3:   Flavors of logged data
 
Flavor Description
H5FD_MEM_NOLIST Error value
H5FD_MEM_DEFAULT Value not yet set.
May also be a datatype set in a larger allocation that will be suballocated by the library.
H5FD_MEM_SUPER Superblock data
H5FD_MEM_BTREE B-tree data
H5FD_MEM_DRAW Raw data (for example, contents of a dataset)
H5FD_MEM_GHEAP Global heap data
H5FD_MEM_LHEAP Local heap data
H5FD_MEM_OHDR Object header data

Returns:
Returns non-negative if successful. Otherwise returns negative.

Fortran90 Interface:
None.

History:

Last modified: 15 May 2009
Name: H5Pset_fapl_mpio
Signature:
herr_t H5Pset_fapl_mpio( hid_t fapl_id, MPI_Comm comm, MPI_Info info )

Purpose:
Stores MPI IO communicator information to the file access property list.

Description:
H5Pset_fapl_mpio stores the user-supplied MPI IO parameters comm, for communicator, and info, for information, in the file access property list fapl_id. That property list can then be used to create and/or open a file.

H5Pset_fapl_mpio is available only in the parallel HDF5 library and is not a collective function.

comm is the MPI communicator to be used for file open, as defined in MPI_FILE_OPEN of MPI-2. This function makes a duplicate of the communicator, so modifications to comm after this function call returns have no effect on the file access property list.

info is the MPI Info object to be used for file open, as defined in MPI_FILE_OPEN of MPI-2. This function makes a duplicate copy of the Info object, so modifications to the Info object after this function call returns will have no effect on the file access property list.

If the file access property list already contains previously-set communicator and Info values, those values will be replaced and the old communicator and Info object will be freed.

Note:
Raw dataset chunk caching is not currently supported when using this file driver in read/write mode. All calls to H5Dread and H5Dwrite will access the disk directly, and H5Pset_cache and H5Pset_chunk_cache will have no effect on performance.

Raw dataset chunk caching is supported when this driver is used in read-only mode.

Parameters:
hid_t fapl_id IN: File access property list identifier
MPI_Comm comm     IN: MPI-2 communicator
MPI_Info info IN: MPI-2 info object

Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Fortran90 Interface: h5pset_fapl_mpio_f
SUBROUTINE h5pset_fapl_mpio_f(prp_id, comm, info, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier
  INTEGER, INTENT(IN) :: comm           ! MPI communicator to be used for 
                                        ! file open as defined in 
                                        ! MPI_FILE_OPEN of MPI-2
  INTEGER, INTENT(IN) :: info           ! MPI info object to be used for 
                                        ! file open as defined in 
                                        ! MPI_FILE_OPEN of MPI-2
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
                                        ! 0 on success and -1 on failure
END SUBROUTINE h5pset_fapl_mpio_f
    

History:

Last modified: 2 May 2013
Name: H5Pset_fapl_mpiposix
Signature:
herr_t H5Pset_fapl_mpiposix( hid_t fapl_id, MPI_Comm comm, hbool_t use_gpfs_hints )

Purpose:
Stores MPI IO communicator information to a file access property list.

Function Removed:
The C functions H5Pset_fapl_mpiposix and H5Pget_fapl_mpiposix and the corresponding Fortran subroutines have been removed from the HDF5 Library at Release 1.8.13. They remain available in earlier releases, through HDF5 Release 1.8.12.

All applications used with HDF5 Release 1.8.13 or later and that use MPI I/O should use the functions H5Pset_fapl_mpio and H5Pget_fapl_mpio or the corresponding Fortran subroutines.

While HDF5’s MPI-POSIX driver (H5Pset_fapl_mpiposix and H5Pget_fapl_mpiposix) once provided performance benefits on some systems, that is no longer the case. HDF5’s MPIO driver (H5Pset_fapl_mpio and H5Pget_fapl_mpio) now provides as good or better performance on all modern systems.

Description:
H5Pset_fapl_mpiposix stores the user-supplied MPI IO parameter comm, for communicator, in the file access property list fapl_id. That property list can then be used to create and/or open the file.

H5Pset_fapl_mpiposix is available only in the parallel HDF5 library and is not a collective function.

comm is the MPI communicator to be used for file open, as defined in MPI_FILE_OPEN of MPI-2. This function does not create a duplicated communicator. Modifications to comm after this function call returns may have an undetermined effect on the file access property list. Users should not modify the communicator while it is defined in a property list.

use_gpfs_hints specifies whether to attempt to use GPFS hints when accessing this file. A value of TRUE (or 1) indicates that the hints should be used, if possible. A value of FALSE (or 0) indicates that the hints should not be used.

Available GPFS hints are known to the HFD5 Library and are not user configurable. They may be used only with GPFS file systems and may improve file access for some applications; the user of a GPFS system is encouraged to experiment by running an application with and without this parameter set.

Note:
Raw dataset chunk caching is not currently supported when using this file driver in read/write mode. All calls to H5Dread and H5Dwrite will access the disk directly, and H5Pset_cache and H5Pset_chunk_cache will have no effect on performance.

Raw dataset chunk caching is supported when this driver is used in read-only mode.

Parameters:
hid_t fapl_id IN: File access property list identifier.
MPI_Comm comm IN: MPI-2 communicator.
hbool_t use_gpfs_hints     IN: Use of GPFS hints.

Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Fortran90 Interface: h5pset_fapl_mpiposix_f
SUBROUTINE h5pset_fapl_mpiposix_f(prp_id, comm, use_gpfs, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: prp_id  ! Property list identifier
  INTEGER, INTENT(IN) :: comm           ! MPI communicator to be used 
                                        ! for file open as defined in 
                                        ! MPI_FILE_OPEN of MPI-2
  LOGICAL, INTENT(IN) :: use_gpfs
  INTEGER, INTENT(OUT) :: hdferr        ! Error code
END SUBROUTINE h5pset_fapl_mpiposix_f
        

History:

Last modified: 14 October 2014
Name: H5Pset_fapl_multi
Signature:
herr_t H5Pset_fapl_multi( hid_t fapl_id, const H5FD_mem_t *memb_map, const hid_t *memb_fapl, const char * const *memb_name, const haddr_t *memb_addr, hbool_t relax )
Purpose:
Sets up use of the multi-file driver.
Description:
H5Pset_fapl_multi sets the file access property list fapl_id to use the multi-file driver.

The multi-file driver enables different types of HDF5 data and metadata to be written to separate files. These files are viewed by the HDF5 library and the application as a single virtual HDF5 file with a single HDF5 file address space. The types of data that can be broken out into separate files include raw data, the superblock, B-tree data, global heap data, local heap data, and object headers. At the programmer's discretion, two or more types of data can be written to the same file while other types of data are written to separate files.

The array memb_map maps memory usage types to other memory usage types and is the mechanism that allows the caller to specify how many files are created. The array contains H5FD_MEM_NTYPES entries, which are either the value H5FD_MEM_DEFAULT or a memory usage type. The number of unique values determines the number of files that are opened.

The array memb_fapl contains a property list for each memory usage type that will be associated with a file.

The array memb_name should be a name generator (a printf-style format with a %s which will be replaced with the name passed to H5FDopen, usually from H5Fcreate or H5Fopen).

The array memb_addr specifies the offsets within the virtual address space, from 0 (zero) to HADDR_MAX, at which each type of data storage begins.

If relax is set to TRUE (or 1), then opening an existing file for read-only access will not fail if some file members are missing. This allows a file to be accessed in a limited sense if just the meta data is available.

Default values for each of the optional arguments are as follows:

memb_map
The default member map contains the value H5FD_MEM_DEFAULT for each element.
memb_fapl
The default value is H5P_DEFAULT for each element.
memb_name
The default string is   %s-X.h5   where   X   is one of the following letters: s    for H5FD_MEM_SUPER
b    for H5FD_MEM_BTREE
r    for H5FD_MEM_DRAW
g    for H5FD_MEM_GHEAP
l    for H5FD_MEM_LHEAP
o    for H5FD_MEM_OHDR
memb_addr
The default setting is that the address space is equally divided among all of the elements:
H5FD_MEM_SUPER -> 0 * (HADDR_MAX/6)
H5FD_MEM_BTREE -> 1 * (HADDR_MAX/6)
H5FD_MEM_DRAW -> 2 * (HADDR_MAX/6)
H5FD_MEM_GHEAP -> 3 * (HADDR_MAX/6)
H5FD_MEM_LHEAP -> 4 * (HADDR_MAX/6)
H5FD_MEM_OHDR -> 5 * (HADDR_MAX/6)
            
Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Example:
The following code sample sets up a multi-file access property list that partitions data into meta and raw files, each being one-half of the address:
                  H5FD_mem_t mt, memb_map[H5FD_MEM_NTYPES];
                  hid_t memb_fapl[H5FD_MEM_NTYPES];
                  const char *memb[H5FD_MEM_NTYPES];
                  haddr_t memb_addr[H5FD_MEM_NTYPES];
 
                  // The mapping...
                  for (mt=0; mt<H5FD_MEM_NTYPES; mt++) {
                     memb_map[mt] = H5FD_MEM_SUPER;
                  }
                  memb_map[H5FD_MEM_DRAW] = H5FD_MEM_DRAW;
 
                  // Member information
                  memb_fapl[H5FD_MEM_SUPER] = H5P_DEFAULT;
                  memb_name[H5FD_MEM_SUPER] = "%s.meta";
                  memb_addr[H5FD_MEM_SUPER] = 0;
 
                  memb_fapl[H5FD_MEM_DRAW] = H5P_DEFAULT;
                  memb_name[H5FD_MEM_DRAW] = "%s.raw";
                  memb_addr[H5FD_MEM_DRAW] = HADDR_MAX/2;
 
                  hid_t fapl = H5Pcreate(H5P_FILE_ACCESS);
                  H5Pset_fapl_multi(fapl, memb_map, memb_fapl,
                                  memb_name, memb_addr, TRUE);
        
Fortran90 Interface: h5pset_fapl_multi_f
SUBROUTINE h5pset_fapl_multi_f(prp_id, memb_map, memb_fapl, memb_name,
                               memb_addr, relax, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T),INTENT(IN)  :: prp_id     ! Property list identifier

  INTEGER,DIMENSION(H5FD_MEM_NTYPES_F),INTENT(IN)          :: memb_map
  INTEGER(HID_T),DIMENSION(H5FD_MEM_NTYPES_F),INTENT(IN)   :: memb_fapl
  CHARACTER(LEN=*),DIMENSION(H5FD_MEM_NTYPES_F),INTENT(IN) :: memb_name
  REAL, DIMENSION(H5FD_MEM_NTYPES_F), INTENT(IN)           :: memb_addr
              ! Numbers in the interval [0,1) (e.g. 0.0 0.1 0.5 0.2 0.3 0.4)
              ! real address in the file will be calculated as X*HADDR_MAX
  LOGICAL, INTENT(IN)  :: relax
  INTEGER, INTENT(OUT) :: hdferr           ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pset_fapl_multi_f
	
History:

Name: H5Pset_fapl_sec2
Signature:
herr_t H5Pset_fapl_sec2( hid_t fapl_id )
Purpose:
Sets the sec2 driver.
Description:
H5Pset_fapl_sec2 modifies the file access property list to use the H5FD_SEC2 driver.
Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Fortran90 Interface: h5pset_fapl_sec2_f
SUBROUTINE h5pset_fapl_sec2_f(prp_id, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN)    :: prp_id  ! Property list identifier
  INTEGER, INTENT(OUT)          :: hdferr  ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pset_fapl_sec2_f
	
History:

Name: H5Pset_fapl_split
Signature:
herr_t H5Pset_fapl_split( hid_t fapl_id, const char *meta_ext, hid_t meta_plist_id, const char *raw_ext, hid_t raw_plist_id )
Purpose:
Emulates the old split file driver.
Description:
H5Pset_fapl_split is a compatibility function that enables the multi-file driver to emulate the split driver from HDF5 Releases 1.0 and 1.2. The split file driver stored metadata and raw data in separate files but provided no mechanism for separating types of metadata.

fapl_id is a file access property list identifier.

meta_ext is the filename extension for the metadata file. The extension is appended to the name passed to H5FDopen, usually from H5Fcreate or H5Fopen, to form the name of the metadata file. If the string %s is used in the extension, it works like the name generator as in H5Pset_fapl_multi.

meta_plist_id is the file access property list identifier for the metadata file.

raw_ext is the filename extension for the raw data file. The extension is appended to the name passed to H5FDopen, usually from H5Fcreate or H5Fopen, to form the name of the rawdata file. If the string %s is used in the extension, it works like the name generator as in H5Pset_fapl_multi.

raw_plist_id is the file access property list identifier for the raw data file.

If a user wishes to check to see whether this driver is in use, the user must call H5Pget_driver and compare the returned value to the string H5FD_MULTI. A positive match will confirm that the multi driver is in use; HDF5 provides no mechanism to determine whether it was called as the special case invoked by H5Pset_fapl_split.

Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Example:
/* Example 1: Both metadata and rawdata files are in the same  */
/*    directory.   Use Station1-m.h5 and Station1-r.h5 as      */
/*    the metadata and rawdata files.                          */
hid_t fapl, fid;
fapl = H5Pcreate(H5P_FILE_ACCESS);
H5Pset_fapl_split(fapl, "-m.h5", H5P_DEFAULT, "-r.h5", H5P_DEFAULT);
fid=H5Fcreate("Station1",H5F_ACC_TRUNC,H5P_DEFAULT,fapl);

/* Example 2: metadata and rawdata files are in different      */
/*    directories.  Use PointA-m.h5 and /pfs/PointA-r.h5 as    */
/*    the metadata and rawdata files.                          */
hid_t fapl, fid;
fapl = H5Pcreate(H5P_FILE_ACCESS);
H5Pset_fapl_split(fapl, "-m.h5", H5P_DEFAULT, "/pfs/%s-r.h5", H5P_DEFAULT);
fid=H5Fcreate("PointA",H5F_ACC_TRUNC,H5P_DEFAULT,fapl);
Fortran90 Interface: h5pset_fapl_split_f
SUBROUTINE h5pset_fapl_split_f(prp_id, meta_ext, meta_plist, raw_ext, &
                               raw_plist, hdferr)
  IMPLICIT NONE
  INTEGER(HID_T),INTENT(IN)   :: prp_id     ! Property list identifier
  CHARACTER(LEN=*),INTENT(IN) :: meta_ext   ! Name of the extension for
                                            ! the metafile filename
  INTEGER(HID_T),INTENT(IN)   :: meta_plist ! Identifier of the meta file
                                            ! access property list
  CHARACTER(LEN=*),INTENT(IN) :: raw_ext    ! Name extension for the raw 
                                            ! file filename
  INTEGER(HID_T),INTENT(IN)   :: raw_plist  ! Identifier of the raw file
                                            ! access property list
  INTEGER, INTENT(OUT) :: hdferr            ! Error code
                                            ! 0 on success and -1 on failure
END SUBROUTINE h5pset_fapl_split_f
	
History:

Name: H5Pset_fapl_stdio
Signature:
herr_t H5Pset_fapl_stdio( hid_t fapl_id )
Purpose:
Sets the standard I/O driver.
Description:
H5Pset_fapl_stdio modifies the file access property list to use the standard I/O driver, H5FD_STDIO.
Parameters:
Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.
Fortran90 Interface: h5pset_fapl_stdio_f
SUBROUTINE h5pset_fapl_stdio_f(prp_id, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN)    :: prp_id  ! Property list identifier
  INTEGER, INTENT(OUT)          :: hdferr  ! Error code
                                           ! 0 on success and -1 on failure
END SUBROUTINE h5pset_fapl_stdio_f
	
History:

Name: H5Pset_fapl_windows
Signature:
herr_t H5Pset_fapl_windows( hid_t fapl_id )

Purpose:
Sets the Windows I/O driver.

Description:
H5Pset_fapl_windows sets the default HDF5 Windows I/O driver on Windows systems.

Since the HDF5 Library uses this driver, H5FD_WINDOWS, by default on Windows systems, it is not normally necessary for a user application to call H5Pset_fapl_windows. While it is not recommended, there may be times when a user chooses to set a different HDF5 driver, such as the standard I/O driver (H5FD_STDIO) or the sec2 driver (H5FD_SEC2), in a Windows application. H5Pset_fapl_windows is provided so that the application can return to the Windows I/O driver when the time comes.

Only the Windows driver is tested on Windows systems; other drivers are used at the application’s and the user’s risk.

Furthermore, the Windows driver is tested and available only on Windows systems; it is not available on non-Windows systems.

Parameters:
hid_t fapl_id     IN: File access property list identifier

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran90 Interface:
None.

History:
Release     C
1.8.0 Function introduced in this release.

Last modified: 18 June 2013
Name: H5Pset_fclose_degree
Signature:
herr_t H5Pset_fclose_degree( hid_t fapl_id, H5F_close_degree_t fc_degree )

Purpose:
Sets the file close degree.

Description:
H5Pset_fclose_degree sets the file close degree property fc_degree in the file access property list fapl_id.

The value of fc_degree determines how aggressively H5Fclose deals with objects within a file that remain open when H5Fclose is called to close that file. fc_degree can have any one of four valid values:

Degree name H5Fclose behavior with no open object in file H5Fclose behavior with open object(s) in file
H5F_CLOSE_WEAK Actual file is closed. Access to file identifier is terminated; actual file close is delayed until all objects in file are closed
H5F_CLOSE_SEMI Actual file is closed. Function returns FAILURE
H5F_CLOSE_STRONG Actual file is closed. All open objects remaining in the file are closed then file is closed
H5F_CLOSE_DEFAULT The VFL driver chooses the behavior. Currently, all VFL drivers set this value to H5F_CLOSE_WEAK, except for the MPI-I/O driver, which sets it to H5F_CLOSE_SEMI.

Note that if a file is opened multiple times without being closed, each open operation must use the same file close degree setting. For example, if a file is already open with H5F_CLOSE_WEAK, an H5Fopen call with H5F_CLOSE_STRONG will fail.

Parameters:
hid_t fapl_id IN: File access property list identifier.
H5F_close_degree_t fc_degree     IN: Pointer to a location containing the file close degree property, the value of fc_degree.

Returns:
Returns a non-negative value if successful. Otherwise returns a negative value.

Fortran90 Interface: h5pset_fclose_degree_f
SUBROUTINE h5pset_fclose_degree_f(fapl_id, degree, hdferr) 
  IMPLICIT NONE
  INTEGER(HID_T), INTENT(IN) :: fapl_id  ! File access property list identifier
  INTEGER, INTENT(IN) :: degree          ! Info about file close behavior 
                                         ! Possible values:
                                         !    H5F_CLOSE_DEFAULT_F
                                         !    H5F_CLOSE_WEAK_F
                                         !    H5F_CLOSE_SEMI_F
                                         !    H5F_CLOSE_STRONG_F
  INTEGER, INTENT(OUT) :: hdferr         ! Error code
                                         ! 0 on success and -1 on failure
END SUBROUTINE h5pset_fclose_degree_f
    

History:
Release     C
1.6.0 Function introduced in this release.

Last modified: 2 May 2014
Name: H5Pset_file_image
Signature:
herr_t H5Pset_file_image( hid_t fapl_id, void *buf_ptr, size_t buf_len )

Purpose:
Sets an initial file image in a memory buffer.

Motivation:
H5Pset_file_image and other elements of HDF5 are used to load an image of an HDF5 file into system memory and open that image as a regular HDF5 file. An application can then use the file without the overhead of disk I/O.

Recommended Reading:
This function is part of the file image operations feature set. It is highly recommended to study the guide “HDF5 File Image Operations” before using this feature set.

See the “See Also” section below for links to other elements of HDF5 file image operations.

Description:
H5Pset_file_image allows an application to provide a file image to be used as the initial contents of a file. Calling H5Pset_file_image makes a copy of the buffer specified in buf_ptr of size buf_len.

Parameters:
hid_t fapl_id      IN: File access property list identifier
void *buf_ptr   IN: Pointer to the initial file image, or NULL if no initial file image is desired
size_t buf_len   IN: Size of the supplied buffer, or 0 (zero) if no initial image is desired

Returns:
Returns a non-negative value if successful; otherwise returns a negative value.

Fortran2003 Interface: h5pset_file_image_f

Signature:

  SUBROUTINE h5pset_file_image_f(fapl_id, buf_ptr, buf_len, hdferr)
    USE iso_c_binding
    IMPLICIT NONE
    INTEGER(HID_T) , INTENT(IN)  :: fapl_id
    TYPE(C_PTR)    , INTENT(IN)  :: buf_ptr
    INTEGER(SIZE_T), INTENT(IN)  :: buf_len
    INTEGER        , INTENT(OUT) :: hdferr

Inputs:

  fapl_id - File access property list identifier
  buf_ptr - Pointer to the initial file image, 
            or C_NULL_PTR if no initial file image is desired
  buf_len - Size of the supplied buffer, or 0 (zero) if no initial image is desired

Outputs:

  hdferr  - Returns 0 if successful and -1 if fails

See Also:
H5LTopen_file_image
 
H5Fget_file_image
 
H5Pget_file_image
 
H5Pset_file_image_callbacks
H5Pget_file_image_callbacks
     HDF5 File Image Operations
     in Advanced Topics in HDF5
 
Within H5Pset_file_image_callbacks:
Callback struct   H5_file_image_callbacks_t
Callback ENUM   H5_file_image_op_t

History:
Release     Change
1.8.13 Fortran subroutine added in this release.
1.8.9 C function introduced in this release.

Last modified: 13 April 2012
Name: H5Pset_file_image_callbacks
Signature:
herr_t H5Pset_file_image_callbacks( hid_t fapl_id, H5_file_image_callbacks_t *callbacks_ptr )

Purpose:
Sets the callbacks for working with file images.

Motivation:
H5Pset_file_image_callbacks and other elements of HDF5 are used to load an image of an HDF5 file into system memory and open that image as a regular HDF5 file. An application can then use the file without the overhead of disk I/O.

Recommended Reading:
This function is part of the file image operations feature set. It is highly recommended to study the guide “HDF5 File Image Operations” before using this feature set.

See the “See Also” section below for links to other elements of HDF5 file image operations.

Description:
H5Pset_file_image_callbacks sets callback functions for working with file images in memory.

H5Pset_file_image_callbacks allows an application to control the management of file image buffers through user defined callbacks. These callbacks can be used in the management of file image buffers in property lists and with certain file drivers.

H5Pset_file_image_callbacks must be used before any file image has been set in the file access property list. Once a file image has been set, the function will fail.

The callback routines set up by H5Pset_file_image_callbacks are invoked when a new file image buffer is allocated, when an existing file image buffer is copied or resized, or when a file image buffer is released from use.

Some file drivers allow the use of user-defined callback functions for allocating, freeing, and copying the driver’s internal buffer, potentially allowing optimizations such as avoiding large malloc and memcpy operations, or to perform detailed logging.

From the perspective of the HDF5 Library, the operations of the image_malloc, image_memcpy, image_realloc, and image_free callbacks must be identical to those of the corresponding C standard library calls (malloc, memcpy, realloc, and free). While the operations must be identical, the file image callbacks have more parameters. The return values of image_malloc and image_realloc are identical to the return values of malloc and realloc. The return values of image_memcpy and image_free differ from the return values of memcpy and free in that the return values of image_memcpy and image_free can also indicate failure.

The callbacks and their parameters, along with a struct and an ENUM required for their use, are described below.

Callback struct and ENUM:
The callback functions set up by H5Pset_file_image_callbacks use a struct and an ENUM that are defined as follows

The struct H5_file_image_callbacks_t serves as a container for the callback functions and a pointer to user-supplied data. The struct is defined as follows:

    typedef struct
    {
        void *(*image_malloc)(size_t size, H5_file_image_op_t file_image_op,
                        void *udata);
        void *(*image_memcpy)(void *dest, const void *src, size_t size,
                        H5_file_image_op_t file_image_op, void *udata);
        void *(*image_realloc)(void *ptr, size_t size,
                        H5_file_image_op_t file_image_op, void *udata);
        herr_t (*image_free)(void *ptr, H5_file_image_op_t file_image_op,
                        void *udata);
        void *(*udata_copy)(void *udata); 
        herr_t (*udata_free)(void *udata); 
        void *udata;
    } H5_file_image_callbacks_t;


Elements of the ENUM H5_file_image_op_t are used by the callbacks to invoke certain operations on file images. The ENUM is defined as follows:

    typedef enum
    {
        H5_FILE_IMAGE_OP_PROPERTY_LIST_SET, 
        H5_FILE_IMAGE_OP_PROPERTY_LIST_COPY, 
        H5_FILE_IMAGE_OP_PROPERTY_LIST_GET, 
        H5_FILE_IMAGE_OP_PROPERTY_LIST_CLOSE, 
        H5_FILE_IMAGE_OP_FILE_OPEN, 
        H5_FILE_IMAGE_OP_FILE_RESIZE, 
        H5_FILE_IMAGE_OP_FILE_CLOSE
    } H5_file_image_op_t;

The elements of the H5_file_image_op_t ENUM are used in the callbacks for the following purposes:

H5_FILE_IMAGE_OP_PROPERTY_LIST_SET
         Passed to the image_malloc and image_memcpy callbacks when a file image buffer is to be copied while being set in a file access property list (FAPL).
H5_FILE_IMAGE_OP_PROPERTY_LIST_COPY
  Passed to the image_malloc and image_memcpy callbacks when a file image buffer is to be copied when a FAPL is copied.
H5_FILE_IMAGE_OP_PROPERTY_LIST_GET
  Passed to the image_malloc and image_memcpy callbacks when a file image buffer is to be copied while being retrieved from a FAPL.
H5_FILE_IMAGE_OP_PROPERTY