lua-enet

$ luarocks install enet

-- server.lua
require "enet"
local host = enet.host_create"localhost:6789"
while true do
    local event = host:service(100)
    if event and event.type == "receive" then
        print("Got message: ", event.data, event.peer)
        event.peer:send(event.data)
    end
end

-- client.lua
require "enet"
local host = enet.host_create()
local server = host:connect("localhost:6789")

local done = false
while not done do
    local event = host:service(100)
    if event then
        if event.type == "connect" then
            print("Connected to", event.peer)
            event.peer:send("hello world")
        elseif event.type == "receive" then
            print("Got message: ", event.data, event.peer)
            done = true
        end
    end
end

server:disconnect()
host:flush()

Reference

enet.host_create([bind_address, peer_count, channel_count, in_bandwidth, out_bandwidth])

Returns a new host. All arguments are optional.

A bind_address of nil makes a host that can not be connected to (typically a client). Otherwise the address can either be of the form <ipaddress>:<port>, <hostname>:<port>, or *:<port>.

Example addresses include "127.0.0.1:8888", "localhost:2232", and "*:6767".

Parameters:

• peer_count max number of peers, defaults to 64
• channel_count max number of channels, defaults to 1
• in_bandwidth downstream bandwidth in bytes/sec, defaults to 0 (unlimited)
• out_bandwidth upstream bandwidth in bytes/sec, defaults to 0 (unlimited)

host:connect(address [, channel_count, data])

Connects a host to a remote host. Returns peer object associated with remote host. The actual connection will not take place until the next host:service is done, in which a "connect" event will be generated.

channel_count is the number of channels to allocate. It should be the same as the channel count on the server. Defaults to 1.

data is an integer value that can be associated with the connect event. Defaults to 0.

host:service([timeout])

Wait for events, send and receive any ready packets. timeout is the max number of milliseconds to be waited for an event. By default timeout is 0. Returns nil on timeout if no events occurred.

If an event happens, an event table is returned. All events have a type entry, which is one of "connect", "disconnect", or "receive". Events also have a peer entry which holds the peer object of who triggered the event.

A "receive" event also has a data entry which is a Lua string containing the data received.

host:check_events()

Checks for any queued events and dispatches one if available. Returns the associated event if something was dispatched, otherwise nil.

host:flush()

Sends any queued packets. This is only required to send packets earlier than the next call to host:service, or if host:service will not be called again.

host:broadcast(data [, channel, flag])

Queues a packet to be sent to all connected peers. See peer:send for arguments.

host:channel_limit(limit)

Sets the maximum number of channels allowed. If it is 0 then the system maximum allowable value is used.

host:bandwidth_limit(incoming, outgoing)

Sets the bandwidth limits of the host in bytes/sec. Set to 0 for unlimited.

peer:send(data [, channel, flag])

Queues a packet to be sent to peer. data is the contents of the packet, it must be a Lua string.

channel is the channel to send the packet on. Defaults to 0.

flag is one of "reliable", "unsequenced", or "unreliable". Reliable packets are guaranteed to arrive, and arrive in the order in which they are sent. Unsequenced packets are unreliable and have no guarantee on the order they arrive. Defaults to reliable.

peer:disconnect([data])

Requests a disconnection from the peer. The message is sent on the next host:service or host:flush.

data is optional integer value to be associated with the disconnect.

peer:disconnect_now([data])

Force immediate disconnection from peer. Foreign peer not guaranteed to receive disconnect notification.

data is optional integer value to be associated with the disconnect.

peer:disconnect_later([data])

Request a disconnection from peer, but only after all queued outgoing packets are sent.

data is optional integer value to be associated with the disconnect.

peer:reset()

Forcefully disconnects peer. The peer is not notified of the disconnection.

peer:ping()

Send a ping request to peer, updates round_trip_time. This is called automatically at regular intervals.

peer:throttle_configure(interval, acceleration, deceleration)

Changes the probability at which unreliable packets should not be dropped.

Parameters:

• interval interval in milliseconds to measure lowest mean RTT
• acceleration rate at which to increase throttle probability as mean RTT declines
• deceleration rate at which to decrease throttle probability as mean RTT increases

peer:receive()

Attempts to dequeue an incoming packet for this peer. Returns nil if there are no packets waiting. Otherwise returns two values: the string representing the packet data, and the channel the packet came from.

Copyright (C) 2011 by Leaf Corcoran

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
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