valid usernames

[Derek Martin]

On Wed, Nov 10, 2004 at 09:07:52PM -0500, Bill McGonigle wrote:
> Now, granted, that's a problem with chown and utilities that accept 
> similar syntax, and chown has been changed lately to honor/prefer:
> 
>   chown charlie:brown somefile

Hmm?  The Linux chown utilities have accepted both forms as long as I
can remember...  The difference is that one is the historic BSD
behavior, and the other is the historic AT&T behavior.  As for one
being prefered, I don't know what makes you say that.  The only
possible explanation seems to be that the man page sometimes mentions
both ':' and '.', and other times omits the '.' when refering to the
separator.  I don't think this can really be interpreted to indicate a
preference though...  It just seems like an oversight to me, probably
caused by the author of the man page favoring the colon.

> but until lots of current software and system scripts are updated 
> you're going to potentially hit some problems with first.last 
> usernames, so the redhat scripts are probably trying to protect you.  
> As wei said, there's always vipw.

But another question is, why would anyone want to use such long
usernames?  It makes for lots of typing, and generally has no benefit.

One possible answer might be, "We want to use e-mail addresses
of the form first.last at my site."  Well, if that's what you want,
you can (and I think probably should) get it by using a more
reasonable username, and mapping the first.last form in sendmail's
virtusertable, or in the aliases file.  If you're not using sendmail,
your MTA probably has a similar feature, though I wouldn't know what
it is...

So, what do I think makes a reasonable user name?  Well, it should be
short, and obviously it should be unique.  For small sites, the user's
initials usually work quite well.  They're short, and the chances of a
namespace collision are relatively small, compared with schemes that
use the first initial and last name, or vice versa.  It's easy to have
two John Smiths at your office, but chances are their middle initials
will be different...

For larger sites, I've come to like the idea of initials plus a unique
identifier, such as an employee number (or last 4 digits, or phone
extension, etc.).  This is still short, and still avoids namespace
collisions.  If your organization is large enough, eventually you will
start having namespace collisions, if you only use names as the basis
of the user name, no matter what kinds of contortions you use to make
it.

-- 
Derek D. Martin    http://www.pizzashack.org/   GPG Key ID: 0xDFBEAD02
-=-=-=-=-
This message is posted from an invalid address.  Replying to it will result in
undeliverable mail.  Sorry for the inconvenience.  Thank the spammers.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: not available
Url : http://mail.gnhlug.org/mailman/private/gnhlug-discuss/attachments/20041110/8d11880e/attachment-0001.bin