IN: Location identifier; may be a file, group, dataset, named datatype or attribute identifier
const char *group_name
IN: Name of group, relative toloc_id, in which object is located
IN: Type of index by which objects are ordered
IN: Order of iteration within index
IN: Object to open
IN: Link access property list
H5O_OPEN_BY_IDX opens thenth object in the group specified byloc_idandgroup_name.
loc_idspecifies a location identifier.group_namespecifies the group relative toloc_idin which the object can be found. Ifloc_idfully specifies the group in which the object resides,group_namecan be a dot (.).
The specific object to be opened within the group is specified byindex_type,order, andnas follows:
index_typespecifies the type of index by which objects are ordered. Valid index types includeH5_INDEX_NAME, indexed by name, andH5_INDEX_CRT_ORDER, indexed by creation order.
orderspecifies the order in which the links are to be referenced for the purposes of this function. Valid orders includeH5_ITER_INCfor increasing order,H5_ITER_DECfor decreasing order, andH5_ITER_NATIVE. Rather than implying a particular order, H5_ITER_NATIVEinstructs the HDF5 library to iterate through the objects in the fastest available order, i.e., in a natural order.
nspecifies the position of the object within the index. Note that this count is zero-based;0(zero) indicates that the function will return the value of the first object; ifnis5, the function will return the value of the sixth object; etc.
Iflapl_idspecifies the link access property list to be used in accessing the object.
An object opened with this function should be closed when it is no longer needed so that resource leaks will not develop.H5O_CLOSEcan be used to close groups, datasets, or committed datatypes.
Returns an object identifier for the opened object if successful; otherwise returns a negative value.