[plt-scheme] about writing scheme extension

>   When writing MzScheme extensions howcome 
> there's only "scheme_initialize()" and 
> "scheme_reload()" but no "scheme_finalize()"
> or "scheme_cleanup()". How can I make sure
> resource allocated by the scheme extension such 
> as shared memory segment are detached after the 
> scheme program quits?

MzScheme currently has no mechanism for "unloading" an extension.
After an extension is loaded, it stays active until MzScheme exits.

To perform an action when MzScheme exits, either atexit() or custodians
plus scheme_add_atexit_closer() should do want you want.

Matthew