php man page for session_destroy

SESSION_DESTROY(3)							 1							SESSION_DESTROY(3)

session_destroy - Destroys all data registered to a session

SYNOPSIS
       bool session_destroy (void  )

DESCRIPTION
       session_destroy(3)  destroys  all of the data associated with the current session. It does not unset any of the global variables associated
       with the session, or unset the session cookie. To use the session variables again, session_start(3) has to be called.

	In order to kill the session altogether, like to log the user out, the session id must also be unset. If a cookie is used to propagate the
       session id (default behavior), then the session cookie must be deleted. setcookie(3) may be used for that.

RETURN VALUES
	Returns TRUE on success or FALSE on failure.

EXAMPLES
       Example #1

	      Destroying a session with $_SESSION

	      <?php
	      // Initialize the session.
	      // If you are using session_name("something"), don't forget it now!
	      session_start();

	      // Unset all of the session variables.
	      $_SESSION = array();

	      // If it's desired to kill the session, also delete the session cookie.
	      // Note: This will destroy the session, and not just the session data!
	      if (ini_get("session.use_cookies")) {
		  $params = session_get_cookie_params();
		  setcookie(session_name(), '', time() - 42000,
		      $params["path"], $params["domain"],
		      $params["secure"], $params["httponly"]
		  );
	      }

	      // Finally, destroy the session.
	      session_destroy();
	      ?>

NOTES
       Note

	       Only use session_unset(3) for older deprecated code that does not use $_SESSION.

SEE ALSO
       unset(3), setcookie(3).

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