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- Subject: Re: C API question
- From: Drake Wilson <drake@...>
- Date: Sun, 9 Jan 2011 11:02:01 -0700
Quoth Sam Roberts <firstname.lastname@example.org>, on 2011-01-09 09:49:13 -0800:
> > And this doesn't solve the problem for modules and other sorts of libraries.
> Trying to guess what the "the problem" is, but for a module, you'd use
> a lightuserdata of a pointer to something in your modules C
> implementation, the module function, a static variable. C doesn't put
> multiple things at the same pointer address, so it will be unique.
Note that last I checked, ISO C proper doesn't guarantee much along
those lines for function pointers. (I think they're not even
guaranteed to be castable to void *.) So declaring a separate char or
int dummy variable is probably best in the general case; the extra few
bytes of memory are a small price to pay for a nice clean pointer
unless you're on a seriously memory-starved system.
---> Drake Wilson