IN THIS APPENDIX
Profiles and POSIX Standards
In the past, the existence of various versions of the UNIX system was a fruitful source of creative and innovative software. However, it has also been a persistent source of frustration for users and programmers. Users who moved between the BSD and System V versions of the system, for example, discovered that commands that worked on one system did not work, or worked differently, on the other. Programmers found a similar phenomenon: Programs that worked on one system behaved differently, or even failed to compile, on another. In 1984 the user's group /usr/group (now called UniForum) started an effort to specify a “standard ...