Re: [Boost-users] [signals] Automatic connection management and MT

From: Frank Mori Hess (frank.hess_at_[hidden])
Date: 2007-02-01 08:37:40

On Tuesday 30 January 2007 22:40 pm, Timmo Stange wrote:
> I'm working on a preliminary solution for an interface-compatible
> but thread-safe implementation of Signals for my project so that I
> will be able to switch to Boost.Signals should Doug Gregor find
> the time to add thread-safety there.
>
> While deciding what parts to include and which to leave out, I
> noticed that the automatic connection management is probably not
> usable in a multi-threaded context in the current form. Using a
> base class destructor (signals::trackable) to monitor an observer's
> lifetime is bound to result in race condition trouble with the order
> of destruction in a class hierarchy.
>
> Has that been discussed somewhere and are there any proposed
> solutions/alternatives?

I hit the same problem, I had to manually disconnect at the beginning of my 
destructors, see

http://article.gmane.org/gmane.comp.lib.boost.user/24356

Thread-safe automatic disconnect from non-static member functions seems 
like it would require some kind of extension to the language itself, like 
a pre-destructor.

I recently did the same thing as you, my signals implementation is 
attached, if you are interested.  The namespaces are different in my 
code, ::boost is ::EPG and ::boost::signals is ::EPG::signalslib.

-- 
Frank