Skip to content
This repository

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP

Extended process registry for Erlang

Fetching latest commit…

Cannot retrieve the latest commit at this time

README.md

The gproc application

The gproc application

Extended process dictionary.

Authors: Ulf Wiger (ulf.wiger@erlang-solutions.com), Joseph Wayne Norton (norton@geminimobile.com).

Extended process dictionary

Gproc is a process dictionary for Erlang, which provides a number of useful features beyond what the built-in dictionary has:

  • Use any term as a process alias

  • Register a process under several aliases

  • Non-unique properties can be registered simultaneously by many processes

  • QLC and match specification interface for efficient queries on the dictionary

  • Await registration, let's you wait until a process registers itself

  • Atomically give away registered names and properties to another process

  • Counters, and aggregated counters, which automatically maintain the total of all counters with a given name

  • Global registry, with all the above functions applied to a network of nodes

An interesting application of gproc is building publish/subscribe patterns. Example:

subscribe(EventType) ->
    %% Gproc notation: {p, l, Name} means {(p)roperty, (l)ocal, Name}
    gproc:reg({p, l, {?MODULE, EventType}}).

notify(EventType, Msg) ->
    Key = {?MODULE, EventType},
    gproc:send({p, l, Key}, {self(), Key, Msg}).

Gproc has a QuickCheck test suite, covering a fairly large part of the local gproc functionality, although none of the global registry. It requires a commercial EQC license, but rebar is smart enough to detect whether EQC is available, and if it isn't, the code in gproc_eqc.erl will be "defined away".

There is also an eunit suite, covering the basic operations for local and global gproc.

By default, ./rebar doc generates Github-flavored Markdown files.If you want to change this, remove the edoc_opts line from rebar.config.

Gproc was first introduced at the ACM SIGPLAN Erlang Workshop in Freiburg 2007 (Paper available here).

Modules

gproc
gproc_app
gproc_dist
gproc_init
gproc_lib
gproc_sup
Something went wrong with that request. Please try again.