Re: Random crashed with threaded application

On Fri, Jun 21, 2013 at 8:29 AM, steve donovan <steve.j.donovan@gmail.com> wrote:

I do something like this in winapi, but it's finicky and I'm wondering under what conditions it can be guaranteed to be stable.

winapi has a thread() function which is defined here:

https://github.com/stevedonovan/winapi/blob/master/winapi.l.c#L1454

It's a daughter state that's meant to run in a separate OS thread.

Here is an example - I have a blocking command connection, and an async socket for notifications.

local winapi = require 'winapi'
local t,c2,err
local addr = arg[2] or 'localhost'
local c = socket.connect(addr,3333)
c:send ('yes\n')
c:receive()
local m = winapi.mutex()
t = winapi.thread(function()
    c2,err = socket.connect(addr,3334)
    if err then
      c:close()
      error('cannot connect to secondary socket '..err)
    end
    while true do
        local res = c2:receive()
        res = res:gsub('\001','\n')
        m:lock()
        io.write(res)
        m:release()
   end
end,'ok')
winapi.sleep(50)

Then there's a function which receives stuff from the console and passes it through the server:

function eval(line)
c:send(line..'\n')
m:lock()
local res = c:receive()
m:release()
return (res or '?'):gsub('\001','\n')
end

(The magic '\001' is just a convention for passing back strings containing newlines)

This version is now much more stable, and the key bit is that the listening socket must be created in the _new thread_....

I'd like any comments about this simple-minded design, since most of the time I just want to just do two things at once with LuaSocket ;)

steve d.