Re: Call for discussion: DLL handling
On Tue, Oct 20, 1998 at 02:31:01PM +0200, Didier Verna wrote:
> Comments, suggestions and questions welcome.
One other general remark. I like this functionality very much, and I
think that in terms of user-interface, this and the current package system
should stay really synchronized. In particular, this means envision the
problems of loading/unloading, concurrent version management, custom-based
installation etc etc.
I have thought a lot about just this. That is the main reason
why there is
a moduel name and version ... so that you can POTENTIALLY have thte same
module at different versions loaded at the same time. Unloading is a lot more
problematic, as just doing a dlclose() to a dynamically loaded object doesnt
get rid of it. It will only really be unmapped when the last reference to
ANYTHING inside it disappears, and considering that the subr will have a
pointer to the handling function, there is always at least one symbol that
will be referencing the DSO. If we really MUSt support unloading, it will
probably require a further module specific function or task code, whose
job it is to unload the module by removing as many references to itself as it
can (i.e. unmap the subr and any Lisp variables). Not impossible, just very
difficult.
--
J. Kean Johnston | "Every day, computers are making people easier
Engineer, SPG | to use" -- Source unknown.
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