[boost] Re: Boost.Threads: Do we need all those mutexes?

From: Michael Glassford (glassfordm_at_[hidden])
Date: 2004-06-29 13:23:48

Michael Glassford wrote:
> Doug Gregor wrote:
> 
>> On Tuesday 29 June 2004 9:15 am, Michael Glassford wrote:
>>
>>>> For that purpose we'll need something like
>>>>
>>>> scoped_lock(mutex&, nolock_t);
>>>
>>>
>>> I'm increasingly liking this syntax, by the way; thanks for 
>>> suggesting it.
>>
>>
>>
>> I don't know the original intention, but my assumption about the 
>> "bool" parameter was that it was intended to be used to check 
>> (run-time) conditions that might eliminate the need for locking under 
>> certain circumstances, e.g.,
>>
>> bool foo(bool threadsafe)
>> {
>>   mutex::scoped_lock l(m, !threadsafe);
>> }
>>
>> Using types such as nolock_t would prevent such a usage.
> 
> 
> I hadn't considered that, but I guess I'll have to now.

Would it be sufficient that the above use case would be supported like this:

     bool foo(bool threadsafe)
     {
         mutex::scoped_lock l(m, unlocked);
         if (!threadsafe) l.lock();
     }

?

Mike