Page 329 - Beginning PHP 5.3

Chapter 10: Preserving State With Query Strings

D irective D escription
session.cookie_ How long the session cookie should last for (in seconds). The
lifetime default is zero, which expires the cookie when the browser is quit.
Set it to a long value (for example, 1 year) to make a semi -
permanent session for storing data such as user preferences.
Alternatively, to increase security for sessions such as login
sessions, set it to a short value, such as 20 minutes. That way,
the session will time out if the user waits more than 20 minutes
between page requests.
session.cookie_path The path field for the session cookie. Defaults to “/” (the entire
site). Set this to a subdirectory of your Web site if you want to
limit the session to scripts inside that folder.
session.cookie_domain The domain field for the session cookie. Defaults to “” (the
current server). Change this if you want the session to be
available to more than one host in the same domain.
session.cookie_ The HttpOnly field for the session cookie. Defaults to false .
httponly Change this to true if you want to prevent JavaScript from
accessing the session cookie.

session.auto_start Defaults to false . Change it to true , and PHP automatically
starts a session the moment your script starts executing, saving
you from calling session_start() . Be careful though; if set to
true you cannot store objects in sessions (because your classes
won ’ t be defined at the time the session data is loaded).

You can either alter these directives directly in your php.ini file, if you have access to it (see Appendix
B for details), or you can set them on a per - script basis using the ini_set() PHP function:

ini_set( “session.cookie_lifetime”, 1200 ); // Set session timeout to 20
minutes
As well as altering session behavior, you can even write your own custom code to store the session data
on the server. For example, instead of letting PHP store the data in temporary files, you might prefer to
store it in a database. How to do this is out of the scope of this book, but you can find out more by
reading http://www.php.net/manual/en/function.session - set - save - handler.php .

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