Re: Timing out LUA programs

[Björn De Meyer <bjorn.demeyer@...>]

Sean Middleditch wrote:
> 
> Again, with Lua's co-threads support, it should be very easy (I would
> imagine - haven't look at internals in a while) to make a
> pre-emptive-ish threading system.  Simply do something akin to forced
> yields, add in Lua mutex/semaphore data types, etc.  The main engine
> would look at all available threads, and run each for X amount of time
> or for X byte-code operations, then return to calling C code.  This way,
> an application could launch Lua threads, and then have a
> "lua_run_threads" call in the main update/event loop.

Well, that could be helpful. Such a Lua would still block when calling 
the C functions, though. Contrary to what I said before, there is no 
truly correct and portable way to do coroutines in plain ANSI C. 
You need system-dependent extensions, and then we're even farther from
home,
so to speak.

On the other hand, it might be the question why you would use a separate 
"microthread" for each and every agent in an AI system. Simply looping 
over all agents in a big (timed) loop, or using some kind
of message passing and/or callbacks can be just as efficient,
not to mention a lot simpler, as you have no pains with mutexes and
semaphores.

-- 
"No one knows true heroes, for they speak not of their greatness." -- 
Daniel Remar.
Björn De Meyer 
bjorn.demeyer@pandora.be