hostname : show or set the host name
[SYNOPSIS] hostname OPTION
OPTION
-a alias names
-A all long host names (FQDNs)
-b set default hostname if none available
-d DNS domain name
-f long host name (FQDN)
-F read host name or NIS domain name from given file
-i addresses for the host name
-I all addresses for the host
-s short host name
-y NIS/YP domain name