Re: question on forcibly stopping a thread

[David Andersen <david@...>]

After reading the "lua_State and garbage collection" thread in 
http://mirrors.dotsrc.org/lua/lua-l-recent.gz I decided to look into 
luaL_ref.  So I googled for "luaL_ref lua_newthread" and found this gem: 
http://sourceforge.net/mailarchive/forum.php?thread_id=5756641&forum_id=32657

The key part of it is saving a reference to the thread:

thread_reference = luaL_ref(L,LUA_REGISTRYINDEX);

and then you can release it with:

luaL_unref (L,LUA_REGISTRYINDEX,thread_reference);

It seems to have cured a null reference exception I was getting in C# 
due to the (apparently) thread being garbage collected.

Is this the right way?


David Morris-Oliveros wrote:
> The way that I'm terminating the thread is by preempting them out, and 
> then removing the reference to them from the global lua table.
>
> I am in charge of multitasking all my coroutines, and i have a class 
> that encapsulates the coroutine, so i keep a variable with the "state" 
> of the thread at any given time, NOT_LOADED, STARTING, RUNNING, 
> SLEEPING, DEAD, KILLED.
>
> So if it's DEAD (because it's finished running), i just clean it up. 
> But I can force the clean up by setting it to KILLED, then removing 
> the references to it from the main globals.
>
> Hope this helps, and hope that I'm not doing anything stupid.
>
> David Andersen wrote:
>
> > I was reading through the mailing list and I saw that you can 
> > forcibly stop a thread by removing all trace of it from the stack.  
> > I'm pretty new to lua, so I'm wondering if anyone can point me in the 
> > right direction.  I am looking for the correct C API commands to use 
> > to pop from the stack.  I'm afraid of introducing a memory leak.
> >
> > Maybe its really easy and I just need to call :
> >
> > threadState = lua_newthread(L);
> > <do stuff>
> > lua_pop(threadState, lua_gettop(threadState));
> >
> > I am using the technique found in this posting to run AI scripts for 
> > a game, so I have lots of threads, and they need to be terminated 
> > immediately when the object they are attached to dies.
> >
> > http://www.icynorth.com/forums/viewtopic.php?p=228&sid=4b08243f0dd2ebe6b8b416fe0bc4eeb4#228