Re: [boost] [extension] Concatenating factory_map objects

From: Jeremy Pack (rostovpack_at_[hidden])
Date: 2008-07-08 19:46:09

Robert,

On Tue, Jul 8, 2008 at 4:12 PM, Robert Dailey <rcdailey_at_[hidden]> wrote:

> <snip>
>

> Yes, your explanation helps out tremendously. However, I noticed that
> load_single_library() simply deletes (by allowing it to fall out of
> scope) the shared_library object it creates as the function returns.
> Does this mean that it does not close the library when it is
> destroyed? So I will need to be responsible for calling
> shared_library::close() to release the DLL when I am done using it?

The load_single_library function is a convenience function designed for the
simple case in which you don't need to close the shared library until
program termination. For more complex usage, just use a shared_library
object.

> I noticed also (you mentioned this) that there's an auto_close
> construction parameter in shared_library, however this value does not
> seem to get used anywhere. In fact, shared_library does not have a
> destructor that I can see. Does automatic unloading of shared
> libraries not work on destruction of shared_library objects even when
> setting auto_close to true?

You're right - I must have accidentally removed the destructor when I last
refactored. Thanks! I'll fix it.

> I'm assuming that by closing a shared_library, any factory objects
> created from that shared_library will not function anymore, since it
> won't have access to the classes it is creating.
>

Yep. Your program will crash or do something worse.

Thanks again for your continued help!
>
> PS: Do you have an online version of the trunk's documentation for
> Boost.Extension? I haven't been able to find this. Thank you.

Docs are available at:
http://redshoelace.dlinkddns.com:9080/boost/doc/extension/index.html

Jeremy Pack