Operations can be performed on objects in the QDLS file system not only through the Document Library Objects (DLO) CL commands but also through either the integrated file system interface or APIs provided by a hierarchical file system (HFS).
Whereas the integrated file system is based on the Integrated Language Environment® (ILE) program model, HFS is based on the original iSeries™ server program model.
The HFS APIs allow you to perform a few additional operations that the integrated file system does not support. In particular, you can use HFS APIs to access and change directory extended attributes (also called directory entry attributes). Be aware that the naming rules for using HFS APIs are different from the naming rules for APIs using the integrated file system interface.