Re: Module unloading

[Neil Jerram]

Rob Browning wrote:
> This made me wonder -- what happens if you dynamically load (dlopen) a
> lib that depends on libguile, and then you later dlclose that lib?
> What happens to libguile?  Presumably it will be unloaded too.  Does
> Guile tolerate that?
>
> If so, does Guile tolerate being re-loaded?  For example if you then
> re-dlopen the lib that depends on libguile and start using it?

What happens "inside" the library when it is dlopened?  I thought 
nothing, so I doubt that loading and unloading per se would be a problem.

If a single program called scm_init_guile() twice without the library 
being unloaded and reloaded first ... I doubt the code would handle 
that, but I'd say this is incorrect use of the API.

If a single program calls scm_init_guile(), later unloads libguile, the 
reloads libguile and calls scm_init_guile() ... I'd say this _ought_ to 
work, and it probably mostly does as long as reloading reinitializes 
libguile's global data.  Since there is no scm_term_guile(), though, I 
suspect we would also have leaked a lot of memory on the heap.

        Neil