What are the fields printed by getent ahosts DOMAIN?
The output for getent hosts is a simple combination of IP and hostname. The getent ahosts has an additional third field that is, in all my test, either STREAM, DGRAM or RAW.
Output for getent hosts example.net
2001:500:88:200::10 example.net
and for getent ahosts example.net
2001:500:88:200::10 STREAM example.net
2001:500:88:200::10 DGRAM
2001:500:88:200::10 RAW
192.0.43.10 STREAM
192.0.43.10 DGRAM
192.0.43.10 RAW