Re: [boost] "joinable"

From: Anthony Williams (anthony.ajw_at_[hidden])
Date: 2008-05-28 08:51:28

Stefan Seefeld <seefeld_at_[hidden]> writes:

> David Abrahams wrote:
>> Seems to me that if we have "detach()," it we should be asking whether a
>> thread is "attached()," rather than "joinable()."  Our documentation
>>   
> Agreed.
>
>> says "if *this refers to a thread of execution..." all over it, which
>> would seem to indicate that joinable() is an important question even
>> when you're not about to join().
>>   
>
> I find this phrasing a bit strange.  'thread of execution' sounds like a 
> concept.
> Is the 'main' thread not a 'thread of execution' ? (And even if no 
> threads are spawned at all ?)

The 'main' thread us a thread of execution, even if no other threads
have been spawned. You cannot obtain a boost::thread object that
references it though.

> If what is referred to is actually an object (as hinted to by the use of 
> '*this', it should be clear by use of an appropriate (type) name 
> ('thread', instead of 'thread of execution').

The *this in question refers to the boost::thread object on which a
member function is being called. A boost::thread object may reference
a thread of execution (whether running or finished), or it may not
reference anything (e.g. a default-constructed boost::thread object).

Anthony
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