sess_read,sess_write etc methods are removed from CI3.0 session library

http://www.codeigniter.com/user_guide/li...sions.html

sess_read() and sess_write() weren't documented methods in the CI 2.x Session library (they existed, but weren't intended to be used directly), so you probably won't find any specific information about replacing calls to those methods. However, the documentation should give you plenty of choices for reading/writing session data.

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