H5P_GET_VIRTUAL_FILENAME takes the dataset creation property list for the virtual dataset,
dcpl_id, the mapping index,
index, the size of the filename for a source dataset,
size, and retrieves the name of the file for a source dataset used in the mapping.
size characters of the filename are returned in
name; additional characters, if any, are not returned to the user application.
If the length of the filename, which determines the required value of
size, is unknown, a preliminary call to H5P_GET_VIRTUAL_FILENAME 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 filename. That value, plus 1 for a
NULL terminator, must then be assigned to
size for a second H5P_GET_VIRTUAL_FILENAME call, which will retrieve the actual filename.