V Sat, 18 Feb 2012 09:00:30 +0100 (CET) Jan Engelhardt <jengelh@medozas.de> napsáno:
I do not see any group name length limit either, however,
(a) there is a limit as to what a user can/want to take. While tabcompletion probably gets you out most of the time, nobody really wants e.g. /home/Karl\ Theodor\ Maria\ Nikolaus\ Johann\ Jacob
Philipp\ Franz\ Joseph\ Sylvester\ Freiherr\ von\ und\ zu\ Guttenberg (21st century, though past-time, German politician serving for this example).(b) not defined by POSIX, but there is an actual sanity limit. A username length about PATH_MAX chars long becomes problematic to be used in a path, e.g. when attempting to use for /home :)
The 16 character limit in Arch is just like the 80 character "limit" in coding. But actually, it is not a limit, but a wellness target: it may be exceeded if there is a justification. In contrast, historic UNIX usernames of 8 chars - /that/ was a limit.
This seems to be a compilation-time configure option GROUP_NAME_MAX_LENGTH...
On Debian (I looked at Knoppix actually), the limit is relaxed a bit: 32 chars.
It can be handled as a distro specific patch, although it complicates portability.
Regards, Milan
http://www.milan-knizek.net/ About linux and photography (Czech only) O linuxu a fotografování