8 uses of MAINTENANCE_MODE

ajax_footer in includes/ajax.inc
Performs end-of-Ajax-request tasks.
drupal_exit in includes/common.inc
Performs end-of-request tasks.
drupal_installation_attempted in includes/bootstrap.inc
Returns TRUE if a Drupal installation is currently being attempted.
error_displayable in includes/errors.inc
Determines whether an error should be displayed.
menu_get_custom_theme in includes/menu.inc
Gets the custom theme for the current page, if there is one.
update_flush_caches in modules/update/update.module
Implements hook_flush_caches().
_drupal_bootstrap_full in includes/common.inc
_drupal_maintenance_theme in includes/theme.maintenance.inc
Sets up the theming system for maintenance page.

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