From: Ben Hutchings (ben.hutchings_at_[hidden])
Date: 2005-03-21 09:43:39
Thorsten Froehlich wrote:
> Hi,
>
> I noticed that when using thread::join and the thread has already
> completed,
I'm not sure whether you mean that the thread has exited or that it has
also been joined.
> at least on Mac OS X using pthreads, pthread_join returns
> EINVAL, thus triggering the assertion res == 0. Is this intentional or
> a bug?
Which part of this behaviour are you questioning?
The reasons why pthread_join may fail all represent bugs rather than
unpredictable errors, hence the assertion. Joining a thread makes the
thread object an empty shell which has no further use. Detaching a
thread also makes it non-joinable and makes the thread object almost
useless. If your program attempts to join a non-joinable thread, that's
the bug. Otherwise, it is conceivable that you have found a bug in
MacOS X or in Boost.Threads, but I'd be surprised.
Ben.