Share files and session details among sub domains

[eluser]max123[/eluser]
I have several related sub domains and I want to share session details and files among sub domains

eg:

http://sub_domain1/abc.com
http://sub_domain2/abc.com
http://sub_domain3/abc.com

there are 3 related web sites for above 3 sub domains. But I want to use the same header and footer views for all the sub domains.

Also once I logged in to the system from sub_domain1, and once I move to sub_domain2 or sub_domain3, still the user should be kept as an already logged user. That means no need to sign in again.

How can I do these 2 things

[eluser]n0xie[/eluser]
Using the same header and viewer is something you can easily do with your views. There are plenty examples to be found on the forum.

To allow the user to stay 'logged in' across all your subdomains:

Code:

$config['cookie_prefix']    = "";
$config['cookie_domain']    = ".abc.com";
$config['cookie_path']        = "/";