Re: determining who is a registered user in your system

[Adam Aube <aaube01@baker.edu>]

Antonio Rodriguez wrote:
> Adam Aube wrote
>> Antonio Rodriguez wrote:

>>> Whats the command to determine who is a registered user in your
>>> system, or to gather stats about them, such as registration time, etc?

>> What do you mean by "registered user"?

> Good question, hmm, the ones that you can unregister with deluser?
> Ls-ing /etc/passwd you can see a bunch of entries.

So you mean system users (those with accounts in /etc/passwd) as opposed to
virtual users (users that only exist in some service's user database).

> Some are system users, necessary for the functioning of the default
> minimal system, some are not.

> Would be great having a command that would spit that out:

AFAIK, there is no such command. However, users created by tools such as
adduser start at UID 1000, so anything with a lower UID was either a
default account created at install time or created by a software package,
and should not be touched without good reason.

> Can the root remove h[i,e][m,r]self from the system?

Of course - just remove the entries from /etc/passwd and /etc/shadow.
However, I would strongly recommend you NOT do this (unless you want to
cripple your system).

Adam