net_adm(3erl) Erlang Module Definition net_adm(3erl)
NAME
net_adm - Various Erlang net administration routines.
DESCRIPTION
This module contains various network utility functions.
EXPORTS
dns_hostname(Host) -> {ok, Name} | {error, Host}
Types:
Host = atom() | string()
Name = string()
Returns the official name of Host, or {error, Host} if no such
name is found. See also inet(3erl).
host_file() -> Hosts | {error, Reason}
Types:
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 can-
not be read or the Erlang terms on the file cannot be inter-
preted.
localhost() -> Name
Types:
Name = string()
Returns the name of the local host. If Erlang was started with
command-line flag -name, Name is the fully qualified name.
names() -> {ok, [{Name, Port}]} | {error, Reason}
names(Host) -> {ok, [{Name, Port}]} | {error, Reason}
Types:
Host = atom() | string() | inet:ip_address()
Name = string()
Port = integer() >= 0
Reason = address | file:posix()
Similar to epmd -names, see erts:epmd(1). Host defaults to the
local host. Returns the names and associated port numbers of the
Erlang nodes that epmd registered at the specified host. Returns
{error, address} if epmd is not operational.
Example:
(arne@dunn)1> net_adm:names().
{ok,[{"arne",40262}]}
ping(Node) -> pong | pang
Types:
Node = atom()
Sets up a connection to Node. Returns pong if it is successful,
otherwise pang.
world() -> [node()]
world(Arg) -> [node()]
Types:
Arg = verbosity()
verbosity() = silent | verbose
Calls names(Host) for all hosts that are specified in the Erlang
host file .hosts.erlang, collects the replies, and then evalu-
ates ping(Node) on all those nodes. Returns the list of all
nodes that are successfully pinged.
Arg defaults to silent. 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() returns {error, Reason}.
world_list(Hosts) -> [node()]
world_list(Hosts, Arg) -> [node()]
Types:
Hosts = [atom()]
Arg = verbosity()
verbosity() = silent | verbose
Same as world/0,1, but the hosts are specified as argument in-
stead of being read from .hosts.erlang.
FILES
File .hosts.erlang consists of a number of host names written as Erlang
terms. It is looked for in the current work directory, the user's home
directory, and $OTP_ROOT (the root directory of Erlang/OTP), in that
order.
The format of file .hosts.erlang must be one host name per line. The
host names must be within quotes.
Example:
'super.eua.ericsson.se'.
'renat.eua.ericsson.se'.
'grouse.eua.ericsson.se'.
'gauffin1.eua.ericsson.se'.
^ (new line)
Ericsson AB kernel 7.0 net_adm(3erl)