Enightening sought: User-ID, Owner & Permission

[Charlie Kravetz]

On Wed, 2008-06-11 at 15:34 +0800, SYNass IT Ubuntu / Linux wrote:
> On Tue, 2008-06-10 at 10:10 -0700, David Fox wrote:
> > On Mon, Jun 9, 2008 at 8:13 PM, SYNass IT Ubuntu / Linux
> > <i-ubux at synass.net> wrote:
> > > My data entered normally are: svobi & my full name !
> > > With my future plan it thought of: sn & its full name ...
> > > ... and the previously used one will be the second one !?
> > 
> > Adding users is pretty much a trivial thing. What is more important,
> > especially when migrating or accessing data between systems, or even
> > new installs, is the file ownership and group id. Permissions are
> > checked by the user id, not the given name. Oftentimes (especially on
> > new installs) the user id given in the installation (and in
> > /etc/password) doesn't match the userid numbers stored in the files'
> > metadata. Often this will happen when switching distributions, because
> > not everyone starts their first  (default) user at user id 500, or
> > 1000, or what have you. So you get a permission denied error even
> > though it may appear you own the files.
> > 
> > So you could change the user name and as long as the user id is kept
> > the same things should work.
> > 
> > Or you could chgrp everything that is in /home/$user to the users
> > group (if it isn't already) and addgroup this new username to the
> > users group. Then everybody in the users group has access to the same
> > files.
> > 
> > The user id should be automatically assigned sequentially stating at 1000.
> 
> Hi David and Thilo
> Thanks for your feedbacks and hints !
> 
> Yes, adding users is a trivial thing and this isn't the specific problem
> I had asked for. ;-)
> 
> If not mistaken: 
> The first user enlisted with the installation / setup shall have some
> special privileges !?
> 
> If this is true:
> What are the consequences when changing from first to second one ???
> 
> Again a sample as currently used:
> his system w/single user: User-ID: his / User name: man
> her system w/single user: User-ID: her / User name; woman
> 
> Intentioned use for future:
> his system (still) w/single user: User: both / User name: fam as / at
> installation / setup PLUS
> to be used normally: User-ID: his / User name: man
> 
> his system (still) w/single user: User: both / User name: fam as / at
> installation / setup PLUS
> to be used normally: User-ID: her / User name: woman
> 
> The difference will only be in the first setup (common) user id and user
> name ...
> ... the previously first / single ones remain and are being 2nd but
> normally and most used 
> for each one !!!
> 
> Sorry if my explanation gets too longwinded. ;-|
> 
> TIA for further enlightening and assistance. ;-)
> Cheers, svobi
> 
I do use the same user name and password on my three systems. I made sure they have the User ID, since I won't have to remember as many logins that way.

You are right, the first user does have special privileges, as it
becomes the root user. There are some things that you can only do as
this user, such as setting up the printer over the network. If there is
a way to do this logged in as the second user, I have yet to find it. It
will ask for the password, but unless I log out and log back in as that
first user, it will refuse to accept it.

Good Luck,

-- 
Charlie Kravetz 
Linux Registered User Number 425914          [http://counter.li.org/]
Never let anyone steal your DREAM.           [http://keepingdreams.com]