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.TH net_adm 3 "kernel 2.12.3" "Ericsson AB" "ERLANG MODULE DEFINITION"
.SH MODULE
net_adm \- Various Erlang Net Administration Routines
.SH DESCRIPTION
.LP
This module contains various network utility functions\&.
.SH EXPORTS
.LP
.B
dns_hostname(Host) -> {ok, Name} | {error, Host}
.br
.RS
.TP
Types
Host = atom() | string()
.br
Name = string()
.br
.RE
.RS
.LP
Returns the official name of \fIHost\fR, or \fI{error, Host}\fR if no such name is found\&. See also \fIinet(3)\fR\&.
.RE
.LP
.B
host_file() -> Hosts | {error, Reason}
.br
.RS
.TP
Types
Hosts = [Host]
.br
Host = atom()
.br
Reason = term()
.br
.RE
.RS
.LP
Reads the \fI\&.hosts\&.erlang\fR file, see the section \fIFiles\fR below\&. Returns the hosts in this file as a list, or returns \fI{error, Reason}\fR if the file could not be read\&. See \fIfile(3)\fR for possible values of \fIReason\fR\&.
.RE
.LP
.B
localhost() -> Name
.br
.RS
.TP
Types
Name = string()
.br
.RE
.RS
.LP
Returns the name of the local host\&. If Erlang was started with the \fI-name\fR command line flag, \fIName\fR is the fully qualified name\&.
.RE
.LP
.B
names() -> {ok, [{Name, Port}]} | {error, Reason}
.br
.B
names(Host) -> {ok, [{Name, Port}]} | {error, Reason}
.br
.RS
.TP
Types
Name = string()
.br
Port = int()
.br
Reason = address | term()
.br
.RE
.RS
.LP
Similar to \fIepmd -names\fR, see \fIepmd(1)\fR\&. \fIHost\fR defaults to the local host\&. Returns the names and associated port numbers of the Erlang nodes that \fIepmd\fR at the specified host has registered\&.
.LP
Returns \fI{error, address}\fR if \fIepmd\fR is not running\&. See \fIinet(3)\fR for other possible values of \fIReason\fR\&.
.nf
(arne@dunn)1> net_adm:names()\&.
{ok,[{"arne",40262}]}
.fi
.RE
.LP
.B
ping(Node) -> pong | pang
.br
.RS
.TP
Types
Node = node()
.br
.RE
.RS
.LP
Tries to set up a connection to \fINode\fR\&. Returns \fIpang\fR if it fails, or \fIpong\fR if it is successful\&.
.RE
.LP
.B
world() -> [node()]
.br
.B
world(Arg) -> [node()]
.br
.RS
.TP
Types
Arg = silent | verbose
.br
.RE
.RS
.LP
This function calls \fInames(Host)\fR for all hosts which are specified in the Erlang host file \fI\&.hosts\&.erlang\fR, collects the replies and then evaluates \fIping(Node)\fR on all those nodes\&. Returns the list of all found nodes, regardless of the return value of \fIping(Node)\fR\&.
.LP
\fIArg\fR defaults to \fIsilent\fR\&. If \fIArg == verbose\fR, the function writes information about which nodes it is pinging to stdout\&.
.LP
This function can be useful when a node is started, and the names of the other nodes in the network are not initially known\&.
.LP
Failure: \fI{error, Reason}\fR if \fIhost_file()\fR returns \fI{error, Reason}\fR\&.
.RE
.LP
.B
world_list(Hosts) -> [node()]
.br
.B
world_list(Hosts, Arg) -> [node()]
.br
.RS
.TP
Types
Hosts = [Host]
.br
Host = atom()
.br
Arg = silent | verbose
.br
.RE
.RS
.LP
As \fIworld/0, 1\fR, but the hosts are given as argument instead of being read from \fI\&.hosts\&.erlang\fR\&.
.RE
.SH FILES
.LP
The \fI\&.hosts\&.erlang\fR file 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 \fI$OTP_ROOT\fR (the root directory of Erlang/OTP), in that order\&.
.LP
The format of the \fI\&.hosts\&.erlang\fR file must be one host name per line\&. The host names must be within quotes as shown in the following example:
.nf
\&'super\&.eua\&.ericsson\&.se\&'\&.
\&'renat\&.eua\&.ericsson\&.se\&'\&.
\&'grouse\&.eua\&.ericsson\&.se\&'\&.
\&'gauffin1\&.eua\&.ericsson\&.se\&'\&.
^ (new line)
.fi
|
