RE: How to create username with "."

On Thu, 2006-09-21 at 10:47 -0500, Aleksandar Milivojevic wrote:
Quoting "Miner, Jonathan W (CSC) (US SSA)" <jonathan.w.miner@xxxxxxxxxxxxxx>:

The chown(1) man page says that a colon ":" is the delimiting character:

NAME
chown - change file owner and group

SYNOPSIS
chown [OPTION]... [OWNER][:[GROUP]] FILE...

Couple of lines down in the same man page is the following sentence:

"If the user name is followed by a colon or dot and a group name (or
numeric group ID), with no spaces between them, the group ownership of
the files is changed as well."

Chown in Linux uses dot as alternative separator between user name and
group name for compatibility with some Unix systems that use dot
separator. Dot was choosen as separator since it is not allowed in
user names. On Unix systems, it is advisable to limit yourself to
8-chars usernames (most utilities will work fine with longer
usernames, but not all of them). And also to limit yourself what
characters you are using.

I can't find any documentation that states the dot character is not
allowed in user names.

In fact I have user names with dots, underscores and @ symbols in them
all of which work as expected.

I was also under the impression that the dot separator in chown was
deprecated in favour of the colon, but the man page certainly doesn't
reflect that.

--
Karl Latiss <karl.latiss@xxxxxxxxxxxxx>
Atvert Systems

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