/*
 *   Creating a dataset attribute.
 */

#include "hdf5.h"
#define FILE "dset.h5"

int main() {

   hid_t       file_id, dataset_id, attribute_id, dataspace_id;  /* identifiers */
   hsize_t     dims;
   int         attr_data[2];
   herr_t      status;

   /* Initialize the attribute data. */
   attr_data[0] = 100;
   attr_data[1] = 200;

   /* Open an existing file. */
   file_id = H5Fopen(FILE, H5F_ACC_RDWR, H5P_DEFAULT);

   /* Open an existing dataset. */
   dataset_id = H5Dopen(file_id, "/dset");

   /* Create the data space for the attribute. */
   dims = 2;
   dataspace_id = H5Screate_simple(1, &dims, NULL);

   /* Create a dataset attribute. */
   attribute_id = H5Acreate(dataset_id, "Units", H5T_STD_I32BE, dataspace_id, H5P_DEFAULT);

   /* Write the attribute data. */
   status = H5Awrite(attribute_id, H5T_NATIVE_INT, attr_data);

   /* Close the attribute. */
   status = H5Aclose(attribute_id);

   /* Close the dataspace. */
   status = H5Sclose(dataspace_id);

   /* Close to the dataset. */
   status = H5Dclose(dataset_id);

   /* Close the file. */
   status = H5Fclose(file_id);
}