Sharing User Library and Session between 2 applications

[eluser]bretticus[/eluser]
Are your front-end and back-end sites in the same virtual host or same domain (not separate subdomains?) If so, it depends on whether you're using sessions in some way. I'm not sure about CI's Session class and whether it distinguishes between application points or not. But essentially, sessions are cookie based. You always have, at least, a cookie token (session id.) Since cookies are domain specific, cookies can be shared over different applications in theory as long as they reside in the same virtual host (same domain.)

As @WanWizard pointed out, you will have to have a seperate (but identical) copy of your auth library under each application (because this is code specific in this case.)

If you want to try some simple hacking, I did provide some suggestions to another user how you might go about sharing libraries across applications.