function system_cron in Drupal 6

Same name and namespace in other branches

1. 8 core/modules/system/system.module \system_cron()
2. 7 modules/system/system.module \system_cron()
3. 9 core/modules/system/system.module \system_cron()
4. 10 core/modules/system/system.module \system_cron()

Implementation of hook_cron().

Remove older rows from flood and batch table. Remove old temporary files.

File

modules/system/system.module, line 1311

Configuration system that lets administrators modify the workings of the site.

Code

function system_cron() {

  // Cleanup the flood.
  db_query('DELETE FROM {flood} WHERE timestamp < %d', time() - 3600);

  // Cleanup the batch table.
  db_query('DELETE FROM {batch} WHERE timestamp < %d', time() - 864000);

  // Remove temporary files that are older than DRUPAL_MAXIMUM_TEMP_FILE_AGE.
  $result = db_query('SELECT * FROM {files} WHERE status = %d and timestamp < %d', FILE_STATUS_TEMPORARY, time() - DRUPAL_MAXIMUM_TEMP_FILE_AGE);
  while ($file = db_fetch_object($result)) {
    if (file_exists($file->filepath)) {

      // If files that exist cannot be deleted, continue so the database remains
      // consistent.
      if (!file_delete($file->filepath)) {
        watchdog('file system', 'Could not delete temporary file "%path" during garbage collection', array(
          '%path' => $file->filepath,
        ), 'error');
        continue;
      }
    }
    db_query('DELETE FROM {files} WHERE fid = %d', $file->fid);
  }
  $core = array(
    'cache',
    'cache_block',
    'cache_filter',
    'cache_page',
    'cache_form',
    'cache_menu',
  );
  $cache_tables = array_merge(module_invoke_all('flush_caches'), $core);
  foreach ($cache_tables as $table) {
    cache_clear_all(NULL, $table);
  }
}