Using bind() to create a server with Lua Socket

Question

Working with LuaSocket, this code works:

local socket = require'socket'
local server = socket.bind('*',51423)
local client = server:accept()

but this code fails:

local socket = require 'socket'
local server = socket.tcp()
server:bind('*',51423)
local client = server:accept()    
--> lua: /tmp/server.lua:4: calling 'accept' on bad self (tcp{server} expected, got userdata)

Yet the documentation for TCP bind implies that the latter should work, stating:

"Note: The function socket.bind is available and is a shortcut for the creation of server sockets."

How can I convert a generic "master" object into a server?

---

The motivation for this is the desire to add a timeout on the bind operation itself:

local socket = require'socket'
local server = socket.tcp()
server:settimeout(2/1000) -- Only wait 2ms when attempting to bind
server:bind('*',51423)

Answer 1

The answer is at the top of the same documentation page (oops):

"A master object can be transformed into a server … with the method listen (after a call to bind)"

It would seem that s = socket.bind(…) is actually equivalent to:

s = socket.tcp()
s:bind(…)
s:listen(32)

I'm not sure why they are split into two functions, but modifying the code to add listen() causes it to work:

local socket = require 'socket'
local server = socket.tcp()
server:bind('*',51423)
server:listen(32)
local client = server:accept()