[Samba] Elementary questions

[Claus Gaisser]

Hello,

don't know if this is the right place for my elementary questions. But
after searching and reading a lot I still have no exhaustive answers for
my obscurities:

If I connect to a samba share via

mount -t cifs //[SERVER]/[SHARE] /[MOUNTPOINT] -o user=[USER]

everything I do within /[MOUNTPOINT] I do as user [USER] on [SERVER]
independently of that user I'm logged in on the client. If this is
correct I don't understand the following:

- On server side there is an user `mutetella` which belongs to group
  `sippe`.
- A share `public` is defined via 
  [public]
  path = /srv/public
  guest ok = yes
  browsable = yes
  write list = @sippe
- The path `/srv/public` owns to `root:sippe`.
- If `/srv/public` has 770 rights and the client has mounted the share
  via ``mount -t cifs //[SERVER]/public /[MOUNTPOINT] -o
  user=mutetella`` on client sied I only have reading access.
- If `/srv/public` has 777 rights on client side I have read/write access.

Why the path of this share needs world read/write permissions?

Thanks for your help!

Claus Gaisser