The use of computer systems, such as workstations, personal computers, minicomputers, and mainframes, in a network environment is pervasive. The Open Systems concept is a major factor in the evolution of these systems. For a system attached to a network, the network provides connectivity to many other systems whose file systems may be very different from the local file system, e.g., the local may be hierarchical and the remote flat. An application has potential access to information located on file systems beyond the local file system. However, there is no standard way for that application to be able to transparently access files on several file systems whose access characteristics may differ from the access characteristics of the local file system. Transparent file access means that remote files are accessed as though they were local.
The Institute of Electrical and Electronics Engineers (IEEE) 1003.8 Transparent File Access (TFA) Working Group of the POSIX Standards Committee (IEEE P1003) has undertaken the development of an application programming interface specification based on the IEEE 1003.1-1990 Standard which:
The IEEE 1003.8 TFA Standard under development is suitable for use by any application, regardless of the application's complexity or the complexity of the file system which the application accesses. For a simple application, such as a word processor, the IEEE 1003.8 TFA Standard provides an access specification for rudimentary file systems, e.g., a flat file system. At the same time, the IEEE 1003.8 TFA Standard provides an access specification for robust file systems, e.g., with read/write consistency and record locking, capable of supporting complex applications, such as a database management system.
This report provides the background needed to understand the IEEE 1003.8 TFA Standard whose development is ongoing as this report is published. This report presents the major issues and problems whose resolution forms the basis of the IEEE 1003.8 TFA Standard. These issues are categorized as:
Some issues are illustrated with examples and demonstrations using NFS, the most widely used implementation for accessing remote files on a network. The issues chosen for demonstration are based on their importance, complexity, and ease of reproducibility.