1net_adm(3)                 Erlang Module Definition                 net_adm(3)
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3
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NAME

6       net_adm - Various Erlang net administration routines.
7

DESCRIPTION

9       This module contains various network utility functions.
10

EXPORTS

12       dns_hostname(Host) -> {ok, Name} | {error, Host}
13
14              Types:
15
16                 Host = atom() | string()
17                 Name = string()
18
19              Returns  the  official name of Host, or {error, Host} if no such
20              name is found. See also inet(3).
21
22       host_file() -> Hosts | {error, Reason}
23
24              Types:
25
26                 Hosts = [Host :: atom()]
27                 Reason =
28                     file:posix() |
29                     badarg |
30                     terminated |
31                     system_limit |
32                     {Line :: integer(), Mod :: module(), Term :: term()}
33
34              Reads file .hosts.erlang, see section Files. Returns  the  hosts
35              in this file as a list. Returns {error, Reason} if the file can‐
36              not be read or the Erlang terms on the  file  cannot  be  inter‐
37              preted.
38
39       localhost() -> Name
40
41              Types:
42
43                 Name = string()
44
45              Returns  the  name of the local host. If Erlang was started with
46              command-line flag -name, Name is the fully qualified name.
47
48       names() -> {ok, [{Name, Port}]} | {error, Reason}
49
50       names(Host) -> {ok, [{Name, Port}]} | {error, Reason}
51
52              Types:
53
54                 Host = atom() | string() | inet:ip_address()
55                 Name = string()
56                 Port = integer() >= 0
57                 Reason = address | file:posix()
58
59              Similar to epmd -names, see erts:epmd(1). Host defaults  to  the
60              local host. Returns the names and associated port numbers of the
61              Erlang nodes that epmd registered at the specified host. Returns
62              {error, address} if epmd is not operational.
63
64              Example:
65
66              (arne@dunn)1> net_adm:names().
67              {ok,[{"arne",40262}]}
68
69       ping(Node) -> pong | pang
70
71              Types:
72
73                 Node = atom()
74
75              Sets  up a connection to Node. Returns pong if it is successful,
76              otherwise pang.
77
78       world() -> [node()]
79
80       world(Arg) -> [node()]
81
82              Types:
83
84                 Arg = verbosity()
85                 verbosity() = silent | verbose
86
87              Calls names(Host) for all hosts that are specified in the Erlang
88              host  file  .hosts.erlang, collects the replies, and then evalu‐
89              ates ping(Node) on all those nodes.  Returns  the  list  of  all
90              nodes that are successfully pinged.
91
92              Arg  defaults  to silent. If Arg == verbose, the function writes
93              information about which nodes it is pinging to stdout.
94
95              This function can be useful when a  node  is  started,  and  the
96              names of the other network nodes are not initially known.
97
98              Returns {error, Reason} if host_file() returns {error, Reason}.
99
100       world_list(Hosts) -> [node()]
101
102       world_list(Hosts, Arg) -> [node()]
103
104              Types:
105
106                 Hosts = [atom()]
107                 Arg = verbosity()
108                 verbosity() = silent | verbose
109
110              Same  as  world/0,1,  but  the  hosts  are specified as argument
111              instead of being read from .hosts.erlang.
112

FILES

114       File .hosts.erlang consists of a number of host names written as Erlang
115       terms.  It is looked for in the current work directory, the user's home
116       directory, and $OTP_ROOT (the root directory of  Erlang/OTP),  in  that
117       order.
118
119       The  format  of  file .hosts.erlang must be one host name per line. The
120       host names must be within quotes.
121
122       Example:
123
124       ^ (new line)
125
126
127
128Ericsson AB                     kernel 5.4.3.2                      net_adm(3)