5 calls to drupal_session_start()

drupal_session_commit in includes/session.inc
Commits the current session, if necessary.
drupal_session_initialize in includes/session.inc
Initializes the session handler, starting a session if needed.
drupal_session_regenerate in includes/session.inc
Called when an anonymous user becomes authenticated or vice-versa.
update.php in ./update.php
Administrative page for handling updates from one Drupal version to another.
_drupal_session_regenerate_existing in includes/session.inc
Regenerates an existing session.

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