Re: [ZooLib-dev] Problems using ZooLib with VS 2005

[<pa...@id...>]

> Hmmm. I just started writing directions on how to browse the cvs 
> repository, how to check out etc, and in checking my instructions I 
> find that nothing's working. It looks like sourceforge is having some 
> difficulties. In the meantime I'm sending you current copies of 
> ZAtomic.cpp/h in a separate message.

Ah, that would explain things, thanks!

> I'm afraid I don't know of differences between VC++ 6-ish and VS 2005 
> that would account for the problems in compiling the assembly code -- 
> it may be that it's stricter in its interpretation of mnemonics, and 
> perhaps the cmpxchg instructions have their operands the wrong way 
> round. I haven't used VC++ et al for years, and nor are any of my 
> current colleagues so ZooLib support for MS dev tools relies on helpful 
> souls pitching in from time to time.

Gotcha.
 
> wrt smart pointers in general -- the boost library has come on a long 
> way in the last few years, and their smart_ptr will likely be in the 
> next version of the standard library. It's not thread-safe, but might 
> suffice for your purposes. Generally, unless you're assigning *to* a 
> shared smart pointer you only need to update the count manipulation 
> with atomic ops. If you are assigning to a shared smart pointer it's 
> often better to simply protect it with some synchronization entity -- 
> it's possible to update a couple of pointers and an associated count 
> safely on PPC using address reservation instructions, and apparently 
> it's also possible on x86, but I suspect it'll need some post Pentium I 
> instruction to do so.

Ah, I think I see what they were talking about on the boost list now when 
they said smart_ptrs are not thread safe, would I be right in thinking a 
ZRef would also need synchronization when assigning?  I was hoping to find 
a reallysmart_ptr I could just use without having to worry about, do you 
have any recommendations?  I`d happily trade some speed in the non speed 
critical parts of my software if it reduced the amount of time I spent 
debugging multithreaded issues.

Thanks,

Paul Nolan, CEO Idruna Software Inc.
http://www.idruna.com