-- | Semisynchronous interprocess communication.
module System.Miniplex (
	module System.Miniplex.Sink,
	module System.Miniplex.Source
-- * Overview
--
-- $over

-- * Implementation
--
-- $impl
) where

import System.Miniplex.Sink
import System.Miniplex.Source

-- $over
-- This module provides interprocess communication channels. This is meant
-- to be used by logger-like programs that want to send status reports to
-- N listeners (where N >= 0).
--
-- Such a logger would 'create' a 'Sink' with a certain tag and just start
-- writing messages to it. Then, at any point a client knowing the tag can
-- 'attach' a 'Source' and receive those messages -- until it disconnects.
-- This is all completely transparent to the logger.
--
-- Because each message is intended to be a complete status update, 'write'
-- does not buffer unsent messages: A client that is not ready to read when
-- a new message arrives will simply skip it (and hopefully continue
-- processing with the next message). However, there is one exception to
-- this rule: A 'Sink' remembers the last message sent and repeats it
-- to newly connected clients. Therefore a client will always receive a
-- message immediately after connecting unless the logger hasn't sent
-- anything so far.

-- $impl
-- The implementation is based on named sockets. Specifically, @'create'
-- \"tag\"@ creates the socket @~\/.miniplex\/tag@. It also spawns a thread
-- to watch it, which in turn spawns one thread per connected client.
-- 'attach' simply connects to this socket; no threads are spawned by
-- "System.Miniplex.Source".