Appendix F. FSS-UTF
(File System Safe UCS5 Transformation format)
An informative annex to ISO10646-1 defines a UCS Transformation Format called UTF-1. This format protects control bytes, specifically the null byte. That is, no byte in a UTF-1 string contains a null. This enables a UTF-1 string to be processed by operations that take special action on a null byte.
However, UTF-1 does not protect the ASCII slash character (/). This character is used as a special character in many file systems. Consequently the X/Open Company Ltd published a transformation format called File System Safe UCS Transformation Format (FSS_UTF). The format is published as an X/Open Preliminary Specification, Document Number:P316. The details are reproduced below.
This appendix is for information only; it does not form part of the Unicode Standard Version 1.1