! * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
!   Copyright by The HDF Group.                                               *
!   All rights reserved.                                                      *
!                                                                             *
!   This file is part of HDF5.  The full HDF5 copyright notice, including     *
!   terms governing use, modification, and redistribution, is contained in    *
!   the LICENSE file, which can be found at the root of the source code       *
!   distribution tree, or in https://www.hdfgroup.org/licenses.               *
!   If you do not have access to either file, you may request a copy from     *
!   help@hdfgroup.org.                                                        *
! * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
!
! This example shows how to create and write a dataset attribute.
! It opens the existing file 'dset.h5', obtains the identifier of
! the dataset "/dset", defines attribute's dataspace,
! creates dataset attribute, writes the attribute, and then closes
! the attribute's dataspace, attribute, dataset, and file.
!
! This example is used in the HDF5 Tutorial.

PROGRAM H5_CRTATT

  USE HDF5 ! This module contains all necessary modules

  IMPLICIT NONE

  CHARACTER(LEN=8), PARAMETER :: filename = "dsetf.h5" ! File name
  CHARACTER(LEN=4), PARAMETER :: dsetname = "dset"     ! Dataset name
  CHARACTER(LEN=9), PARAMETER :: aname = "attr_long"   ! Attribute name

  INTEGER(HID_T) :: file_id       ! File identifier
  INTEGER(HID_T) :: dset_id       ! Dataset identifier
  INTEGER(HID_T) :: attr_id       ! Attribute identifier
  INTEGER(HID_T) :: aspace_id     ! Attribute Dataspace identifier
  INTEGER(HID_T) :: atype_id      ! Attribute Dataspace identifier
  INTEGER(HSIZE_T), DIMENSION(1) :: adims = (/2/) ! Attribute dimension
  INTEGER     ::   arank = 1                      ! Attribute rank
  INTEGER(SIZE_T) :: attrlen    ! Length of the attribute string

  CHARACTER(LEN=80), DIMENSION(2) ::  attr_data  ! Attribute data

  INTEGER     ::   error ! Error flag
  INTEGER(HSIZE_T), DIMENSION(1) :: data_dims

  !
  ! Initialize attribute's data
  !
  attr_data(1) = "Dataset character attribute"
  attr_data(2) = "Some other string here     "
  attrlen = 80
  !
  ! Initialize FORTRAN interface.
  !
  CALL h5open_f(error)
  !
  ! Open an existing file.
  !
  CALL h5fopen_f (filename, H5F_ACC_RDWR_F, file_id, error)
  !
  ! Open an existing dataset.
  !
  CALL h5dopen_f(file_id, dsetname, dset_id, error)
  !
  ! Create scalar data space for the attribute.
  !
  CALL h5screate_simple_f(arank, adims, aspace_id, error)
  !
  ! Create datatype for the attribute.
  !
  CALL h5tcopy_f(H5T_NATIVE_CHARACTER, atype_id, error)
  CALL h5tset_size_f(atype_id, attrlen, error)
  !
  ! Create dataset attribute.
  !
  CALL h5acreate_f(dset_id, aname, atype_id, aspace_id, attr_id, error)
  !
  ! Write the attribute data.
  !
  data_dims(1) = 2
  CALL h5awrite_f(attr_id, atype_id, attr_data, data_dims, error)
  !
  ! Close the attribute.
  !
  CALL h5aclose_f(attr_id, error)
  !
  ! Close the attribute datatype.
  !
  CALL h5tclose_f(atype_id, error)
  !
  ! Terminate access to the data space.
  !
  CALL h5sclose_f(aspace_id, error)
  !
  ! End access to the dataset and release resources used by it.
  !
  CALL h5dclose_f(dset_id, error)
  !
  ! Close the file.
  !
  CALL h5fclose_f(file_id, error)
  !
  ! Close FORTRAN interface.
  !
  CALL h5close_f(error)

END PROGRAM H5_CRTATT

