The z/OS UNIXdomainname command
is a synonym for the z/OS UNIXdnsdomainname command.
See Using the z/OS UNIX dnsdomainname command for information about
using this command.
Note: On some operating systems, the domainname command
displays the system NIS/YP domain name, which might or might not be
the same as the system DNS domain name. Portable shell scripts must
use dnsdomainname rather than domainname if
this distinction is important.