Last modified: 9 October 2014
Name: H5Aopen_by_name
Signature:
  hid_t `H5Aopen_by_name`( hid_t `loc_id`, const char *`obj_name`, const char *`attr_name`, hid_t `aapl_id`, hid_t `lapl_id` )

Purpose:
  Opens an attribute for an object by object name and attribute name.

Description:
  `H5Aopen_by_name` opens an existing attribute, `attr_name`, that is attached to an object specified by location and name, `loc_id` and `obj_name`, respectively.

  `loc_id` specifies a location from which the target object can be located and `obj_name` is an object name relative to `loc_id`. If `loc_id` fully specifies the object to which the attribute is attached, `obj_name` should be `'.'` (a dot).

  The attribute access property list, `aapl_id`, is currently unused and should currently be `H5P_DEFAULT`.

  The link access property list, `lapl_id`, may provide information regarding the properties of links required to access the object, `obj_name`. See “Link Access Properties” in the H5P APIs.

  This function, `H5Aopen`, or `H5Aopen_by_idx` must be called before an attribute can be accessed for any further purpose, including reading, writing, or any modification.

  The attribute identifier returned by this function must be released with `H5Aclose` or resource leaks will develop.

Parameters:

  hid_t `loc_id` | IN: Location from which to find object to which attribute is attached
  const char *`obj_name` | IN: Name of object to which attribute is attached, relative to `loc_id`
  const char *`attr_name` | IN: Name of attribute to open
  hid_t `aapl_id` | IN: Attribute access property list (Currently unused; should be passed in as `H5P_DEFAULT`.)
  hid_t `lapl_id` | IN: Link access property list

Returns:
  Returns an attribute identifier if successful; otherwise returns a negative value.

Fortran90 Interface: h5aopen_by_name_f

      SUBROUTINE h5aopen_by_name_f(loc_id, obj_name, attr_name, attr_id, hdferr, &
            aapl_id, lapl_id)
        IMPLICIT NONE
        INTEGER(HID_T), INTENT(IN) :: loc_id
                                           ! Location identifier
        CHARACTER(LEN=*), INTENT(IN) :: obj_name
                                           ! Object name either relative to loc_id,
                                           ! absolute from file’s root group, or '.'
        CHARACTER(LEN=*), INTENT(IN) :: attr_name
                                           ! Attribute name
        INTEGER(HID_T), INTENT(OUT) :: attr_id
                                           ! Attribute identifier
        INTEGER, INTENT(OUT) :: hdferr     ! Error code:
                                           ! 0 on success and -1 on failure

        INTEGER(HID_T), OPTIONAL, INTENT(IN) :: aapl_id
                                           ! Attribute access property list
                                           ! (Currently unused; set to H5P_DEFAULT_F)
        INTEGER(HID_T), OPTIONAL, INTENT(IN) :: lapl_id
                                           ! Link access property list identifier
      END SUBROUTINE

See Also:
  “Using Identifiers”

History:

  Release | C
  1.8.0 | Function introduced in this release.