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

6       erl_epmd -
7           Erlang interface towards epmd
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DESCRIPTION

11       This  module  communicates with the EPMD daemon, see epmd. To implement
12       your own epmd module please see ERTS User's Guide: How to Implement  an
13       Alternative Node Discovery for Erlang Distribution
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EXPORTS

16       start_link() -> {ok, pid()} | ignore | {error, term()}
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18              This  function  is invoked as this module is added as a child of
19              the erl_distribution supervisor.
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21       register_node(Name, Port) -> Result
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23       register_node(Name, Port, Driver) -> Result
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25              Types:
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27                 Name = string()
28                 Port = integer() >= 0
29                 Driver = inet_tcp | inet6_tcp | inet | inet6
30                 Creation = integer() >= 0
31                 Result =  {ok,  Creation}  |  {error,  already_registered}  |
32                 term()
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34              Registers  the  node  with epmd and tells epmd what port will be
35              used for the current node. It returns a  creation  number.  This
36              number  is incremented on each register to help with identifying
37              if a node is reconnecting to epmd.
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39       port_please(Name, Host) -> {ok, Port, Version} | noport
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41       port_please(Name, Host, Timeout) -> {ok, Port, Version} | noport
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43              Types:
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45                 Name = atom() | string()
46                 Host = atom() | string() | inet:ip_address()
47                 Timeout = integer() >= 0 | infinity
48                 Port = Version = integer() >= 0
49
50              Requests the distribution port for the given  node  of  an  EPMD
51              instance.  Together with the port it returns a distribution pro‐
52              tocol version which has been 5 since Erlang/OTP R6.
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54       address_please(Name, Host, AddressFamily) ->
55                         Success | {error, term()}
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57              Types:
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59                 Name = string()
60                 Host = string() | inet:ip_address()
61                 AddressFamily = inet | inet6
62                 Port = Version = integer() >= 0
63                 Success =
64                     {ok, inet:ip_address()} |
65                     {ok, inet:ip_address(), Port, Version}
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67              Called by the distribution module. Resolves the Host  to  an  IP
68              address.
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70              Another  epmd  module  may return port and distribution protocol
71              version as well.
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73       names(Host) -> {ok, [{Name, Port}]} | {error, Reason}
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75              Types:
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77                 Host = atom() | string() | inet:ip_address()
78                 Name = string()
79                 Port = integer() >= 0
80                 Reason = address | file:posix()
81
82              Called by  net_adm:names/0.  Host  defaults  to  the  localhost.
83              Returns  the  names  and  associated  port numbers of the Erlang
84              nodes that  epmd  registered  at  the  specified  host.  Returns
85              {error, address} if epmd is not operational.
86
87              Example:
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89              (arne@dunn)1> erl_epmd:names(localhost).
90              {ok,[{"arne",40262}]}
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94Ericsson AB                      kernel 6.5.2                      erl_epmd(3)