20182018 Ericsson AB. All Rights Reserved. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. erl_epmd Timmo Verlaan 1 2018-02-19 A
erl_epmd Erlang interface towards epmd

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

 Callback for erl_distribution supervisor.

This function is invoked as this module is added as a child of the erl_distribution supervisor.

 Registers the node with epmd.

Registers the node with epmd and tells epmd what port will be used for the current node. It returns a creation number. This number is incremented on each register to help with identifying if a node is reconnecting to epmd.

 Returns the port number for a given node.

Requests the distribution port for the given node of an EPMD instance. Together with the port it returns a distribution protocol version which has been 5 since Erlang/OTP R6.

 Returns address and port.

Called by the distribution module. Resolves the Host to an IP address.

Another epmd module may return port and distribution protocol version as well.

 Names of Erlang nodes at a host.

Called by net_adm:names/0. Host defaults to the localhost. 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> erl_epmd:names(localhost).
{ok,[{"arne",40262}]}