Notification of any change to a non-local variable.

[Ron Bessems <ron.b@...>]

Question for you all, we need to get a notification every time
any global variable is modified in lua 5.0.

I've looked at chapter 13.4 (table access meta-methods) but it seems
that those access methods cannot track if a variable already exists,
so then a proxy table is used, but then we loose the ability to
iterate over the table.

Is there some way to go into the Lua Source code to do this? Anything
that allows us to hook global variable access notifications? We are
very much locked into Lua 5.0 so sadly can't upgrade to 5.1. I am a
C/C++ coder so I can work on the lua code if needed, a few pointers
where to start would be great.

Thanks,

Ron