H5Acreate2 example: Show how to create an attribute for a dataset and a group
file=H5Fopen("example.h5", H5F_ACC_RDWR, H5P_DEFAULT);
/* Describe the size of the array and create the data space */
dimsf[0] = H5S_UNLIMITED;
dimsf[1] = H5S_UNLIMITED;
dataspace = H5Screate_simple(rank, dimsf, NULL);
dataset = H5Dcreate2(file, "Dataset1", H5T_UINT8, dataspace, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
<Write data to first dataset>
/* Create an attribute for the dataset */
attr = H5Acreate2(dataset, "Attr1", H5T_INT32, H5S_SCALAR, H5P_DEFAULT, H5P_DEFAULT);
/* Write attribute information */
H5Awrite(attr, H5T_INT32, &attr_data);
group = H5Gcreate2(file, "/Group One", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
/* Create an attribute for the dataset */
attr = H5Acreate2(group, "Attr1", H5T_INT32, H5S_SCALAR, H5P_DEFAULT, H5P_DEFAULT);
/* Write attribute information */
H5Awrite(attr, H5T_INT32, &attr_data);