Re: [boost] [thread] Questions about TSS

From: Peter Dimov (pdimov_at_[hidden])
Date: 2008-03-04 14:26:24

Andrey Semashev:

> Peter Dimov wrote:
...

>> thread_specific_ptr was more or less intended to provide a C++ equivalent 
>> to
>> pthread_setspecific, and the POSIX interface associates a single 
>> destructor
>> function to a TSD slot. It's technically possible to emulate shared_ptr, 
>> but
>> is there a reason for that?
>
> There is no specific reason for that. That feature would just follow
> from the interface if thread_specific_ptr was consistent with shared_ptr.

But it's not (semantically) consistent with shared_ptr at all. Making it 
syntactically consistent will just mislead more people. One could even argue 
that it needs to be made even less syntactically consistent with a smart 
pointer than it is now, because it's not like other smart pointers at all. 
Depending on how one looks at it, it represents either a TSD key or an 
auto_ptr with a thread-local storage class.

> Besides, overall interface consistency is a sign of a good library design.

Good use of consistency is a sign of good design. Consistency alone is not.