On Mon, Aug 31, 2009 at 8:32 PM, Rajeev Rao
This is the first time I'm using boost in a multi-threaded env (linux x86_64,gcc 4).
This question may have been asked in other forms. However, from what I've been able to search (google) up, I could not get a crystal clear answer. I'm essentially trying to use the solution provided in this page.
http://onlamp.com/pub/a/onlamp/2006/05/04/smart-pointers.html?page=5.
From the boost documentation, it appears that this could be an undefined operation as the global shared pointer is being read and written to by multiple threads. Is that correct ?
In case the link fails or someone wants more details, please read on.
I've got a n reader threads and 1 writer thread.
initializion Thread : shared_ptr< MyClass > global_ptr(createNewObject()) ;
WriterThread : global_ptr.reset( createNewObject())
ReaderThreads: weak_ptr<MyClass> local_weak_ptr (globally_ptr) ; ...
if(shared_ptr< MyClass > local_shared_ptr = local_weak_ptr.lock() ) { // using local_shared_ptr. } else { // recreate weak ptr from global ? }
thanks.
Rajeev
I don't think that code is thread-safe. You can modify the shared count safely between threads, but you can't modify the pointer itself. Tony