What about a hash of global locks keyed on file name? Or would that be  
too expensive?

Sent from my iPhone

On Nov 11, 2008, at 7:40 PM, Charles Oliver Nutter <charles.nutter / sun.com 
 > wrote:

> Dave Thomas wrote:
>> It would seem that many of the global $ variables would need  
>> protecting from concurrent access from multiple threads. So,  
>> wouldn't it solve the problem simply to have a mutex (or set of  
>> mutexes) to controll access to these, and then claim the mutex  
>> associated with $" while doing the require?
>
> A single global lock would avoid deadlock...but would also prevent  
> any other threads from running while a require was in process. That  
> may or may not be acceptable; but I don't think we should prevent  
> independent threads from requiring *different* files at the same  
> time in any case.
>
> - Charlie
>