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.