Re: [Boost-bugs] [Boost C++ Libraries] #7668: thread_group::join_all() should check whether its threads are joinable

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #7668: thread_group::join_all() should check whether its threads are joinable
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-01-10 21:04:09

#7668: thread_group::join_all() should check whether its threads are joinable
------------------------------------+---------------------------------------
  Reporter:  boost.lists@…          |       Owner:  viboes             
      Type:  Bugs                   |      Status:  closed             
 Milestone:  Boost 1.53.0           |   Component:  thread             
   Version:  Boost 1.52.0           |    Severity:  Problem            
Resolution:  fixed                  |    Keywords:  thread;thread_group
------------------------------------+---------------------------------------

Comment (by viboes):

 Replying to [comment:10 Andrew Molyneux <andrew.molyneux@…>]:
 > > No. I thread that finish normally is still joinable. From where are
 you deducing this?
 > I thought I'd observed it, but on further investigation the situation is
 a bit more complex. My code is actually using thread::timed_join()
 periodically, to check if the thread is still running. I've distilled it
 down to the following code, which triggers the behaviour that surprised
 me:
 > {{{#!C++
 > void threadFunction()
 > {
 >   boost::this_thread::sleep(boost::posix_time::millisec(100));
 > }
 >
 > int main(int argc, char* argv[])
 > {
 >   boost::thread theThread(threadFunction);
 >   // Wait long enough to be fairly certain that the thread has finished
 >   boost::this_thread::sleep(boost::posix_time::millisec(200));
 >   if (!theThread.timed_join(boost::posix_time::millisec(0)))
 >   {
 >     cout << "Thread still running???" << endl;
 >     return 1;
 >   }
 >   theThread.join();
 > }
 > }}}
 >
 > When I run that code, I get an exception on the call to
 theThread.join(), complaining that the thread is not joinable. It seems
 that after theThread.timed_join() succeeds, the thread is no longer
 joinable. Is this the expected behaviour?

 Yes, I confirm.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7668#comment:12>
Boost C++ Libraries <http://www.boost.org/>
Boost provides free peer-reviewed portable C++ source libraries.