H5P_GET_VIRTUAL_DSETNAME takes the dataset creation property list for the virtual dataset,
dcpl_id, the mapping index,
index, the size of the dataset name for a source dataset,
size, and retrieves the name of the source dataset used in the mapping.
size characters of the dataset name are returned in
name; additional characters, if any, are not returned to the user application.
If the length of the dataset name, which determines the required value of
size, is unknown, a preliminary call to H5P_GET_VIRTUAL_DSETNAME with the last two parameters set to
NULL and zero respectively can be made. The return value of this call will be the size in bytes of the dataset name. That value, plus 1 for a
NULL terminator, must then be assigned to
size for a second H5P_GET_VIRTUAL_DSETNAME call, which will retrieve the actual dataset name.