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 cannot be read or the Erlang terms on the
              file cannot be interpreted.

       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 evaluates  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 instead 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)