(Removed) This hook is invoked during all CiviCRM form validation. An array of errors detected is returned. Else we assume validation succeeded.
This hook was removed in v4.7.
hook_civicrm_validate($formName, &$fields, &$files, &$form)
$formName- The name of the form.
&$fields- the POST parameters as filtered by QF
&$files- the FILES parameters as sent in by POST
&$form- the form object
- mixed - formRule hooks return a boolean or an array of error messages which display a QF Error