Re: [Boost-users] [Boost-Threads] Assertion during a second call to thread::join()

From: Sascha Seewald (vudu_at_[hidden])
Date: 2006-08-24 03:05:27

Aubrey, Jason wrote:
> Hi,
> 
> Does anyone know the reason for the behavior in the following example 
> program?
> 
> This example attempts to simulate the scenario where two threads wait on 
> a third thread.  However, I realize that the following is actually one 
> thread waiting on a second thread twice.
> 
> Regards,
> Jason
> 
> My Environment: MSVC 8.0, boost v1.33.1
> 
> #include <boost/thread/thread.hpp>
> #include <boost/thread/xtime.hpp>
> 
> void f()
> {
> }
> 
> void main()
> {
>     boost::thread t(f);
>     t.join();
>     t.join(); // Causes an assertion

A call to thread::join() requires the thread to be joinable. After the 
first call to join() the thread has finished and is not joinable anymore.
If you'd like to execute f twice, create a seperate thread for each run.

hth

Sascha