[Samba] What is the purpose of "add user script"?

[MargoAndTodd]

Hi All,

    I am confused.  In one of the examples of a PDC,
the following smb.conf parameter is given:

    add user script = /usr/sbin/useradd -m -G users '%u'

If you have "passdb backend = tdbsam" and the way
to add users to "tdbsam" is "pdbedit -a -u username",
what is the purpose of the "add user script"?

I am thinking it is to add the user to /etc/passwd,
but "why"?  I add my users from the command line.
I invoke "useradd" then "pdbedit".

What is the purpose of the "add user script"?

Many thanks,
-T