Adding Users Command line

[Bob McClure Jr]

On Tue, Oct 17, 2006 at 01:16:14PM -0700, Bret Stern wrote:
> 
> 
> When adding users from the (command line)
> 
> useradd 
> 
> has an option -r which assigns a specific user id.

Nope, that tells it to assign a "system-level" user id number, usually
less than 500 or 1000.  These are designed for pseudo users assigned
to subsystems and processes like mysql, procmail, backup, bin, et al.

> Is it common to explicitly assign a user id?

Only if you want to make it the same as on another system or to force
a duplicated UID.

> What happens if I don't specifically assign a user id?

It takes the next available UID in the desired range.  That's usually
figured by taking the highest occupied UID in the range and adding
one.

> I'm assuming two users cannot have the same user id,
> so..how would you know the user id's of all your users?

You don't need to, but if you must, look at the third field (delimited
by ':') in /etc/passwd.  Unless you have some good reason to specify a
UID, just let the system assign one.

> Thanks

Cheers,
-- 
Bob McClure, Jr.             Bobcat Open Systems, Inc.
bob at bobcatos.com             http://www.bobcatos.com
"Where you go in the hereafter depends on what you were after here."
  - Thanks to Graffiti, 2 March 2004