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.