#### 6.61.2 Darwin Format Checks

In addition to the full set of format archetypes (attribute format style arguments such as `printf`, `scanf`, `strftime`, and `strfmon`), Darwin targets also support the `CFString` (or `__CFString__`) archetype in the `format` attribute. Declarations with this archetype are parsed for correct syntax and argument types. However, parsing of the format string itself and validating arguments against it in calls to such functions is currently not performed.

Additionally, `CFStringRefs` (defined by the `CoreFoundation` headers) may also be used as format arguments. Note that the relevant headers are only likely to be available on Darwin (OSX) installations. On such installations, the XCode and system documentation provide descriptions of `CFString`, `CFStringRefs` and associated functions.