pcap_datalink_name_to_val(3pcap) on macOS
The text aff198b13536, as Mac OS X 10.6.8, Mac OS X 10.6.7, Mac OS X 10.6.6, Mac OS X 10.6.5, Mac OS X 10.6.4, Mac OS X 10.6.3, Mac OS X 10.6.2, Mac OS X 10.6.1, Mac OS X 10.6 shipped it.
get the link-layer header type value corresponding to a header type name