doFCKeditorSave in CKEditor

What is the equivalent of "doFCKeditorSave" in CKEditor? I have to adapt the following code to work for CKEditor. It needs to save the CKEditor form.

Drupal.Ajax.plugins.FCKEditor = function(hook, args) {
  if (hook === 'submit') {
    if (window.doFCKeditorSave) {
      doFCKeditorSave();
    }
  }
  return true;
}

Many thanks.