-spec dns_hostname(Host) -> {ok, Name} | {error, Host} when Host :: atom() | string(), Name :: string().

Returns the official name of Host, or {error, Host} if no such name is found. See also inet.

-spec host_file() -> Hosts | {error, Reason}
                   when
                       Hosts :: [Host :: atom()],
                       Reason ::
                           file:posix() |
                           badarg | terminated | system_limit |
                           {Line :: integer(), Mod :: module(), Term :: term()}.

Reads file .hosts.erlang, see section Files. Returns the hosts in this file as a list. Returns {error, Reason} if the file cannot be read or the Erlang terms on the file cannot be interpreted.

-spec localhost() -> Name when Name :: string().

Returns the name of the local host. If Erlang was started with command-line flag -name, Name is the fully qualified name.

-spec names() -> {ok, [{Name, Port}]} | {error, Reason}
               when Name :: string(), Port :: non_neg_integer(), Reason :: address | file:posix().

Equivalent to names(net_adm:localhost()).

-spec names(Host) -> {ok, [{Name, Port}]} | {error, Reason}
               when
                   Host :: atom() | string() | inet:ip_address(),
                   Name :: string(),
                   Port :: non_neg_integer(),
                   Reason :: address | file:posix().

Returns the names and associated port numbers of the Erlang nodes that epmd registered at the specified host.

Similar to epmd -names, see erts:epmd.

Returns {error, address} if epmd is not operational.

Example:

(arne@dunn)1> net_adm:names().
{ok,[{"arne",40262}]}

-spec ping(Node) -> pong | pang when Node :: atom().

Sets up a connection to Node. Returns pong if it is successful, otherwise pang.

-spec world() -> [node()].

Equivalent to world(silent).

-spec world(Arg) -> [node()] when Arg :: verbosity().

Calls names(Host) for all hosts that are specified in the Erlang host file .hosts.erlang, collects the replies, and then evaluates ping(Node) on all those nodes. Returns the list of all nodes that are successfully pinged.

If Arg == verbose, the function writes information about which nodes it is pinging to stdout.

This function can be useful when a node is started, and the names of the other network nodes are not initially known.

Returns {error, Reason} if host_file/0 returns {error, Reason}.

-spec world_list(Hosts) -> [node()] when Hosts :: [atom()].

Equivalent to world_list(Hosts, silent).

-spec world_list(Hosts, Arg) -> [node()] when Hosts :: [atom()], Arg :: verbosity().

Same as world/0,1, but the hosts are specified as argument instead of being read from .hosts.erlang.