Re: [Boost-users] Assertion `!pthread_mutex_destroy(&m)' failed.

25 Mar 2011


      AMDG

On 03/25/2011 12:58 PM, Panagiotis Foteinos wrote:
...
I am new to boost:threads, so my apologies in advance.
I am getting an assertion failure right before main() exits. Specifically, I
get the following error: "*/usr/include/boost/thread/pthread/mutex.hpp:45:
boost::mutex::~mutex(): Assertion `!pthread_mutex_destroy(&m)' failed.*"
Below is the code snippet:
***********************************************************************************************************************************
class Test
{
private:
     boost::mutex mtx;
public:
     int counter;
     Test()
     {
         counter = 10;
     }
     void DoWork()
     {
         for(unsigned int i = 0; i<  1000000; i++)
         {
             mtx.try_lock();
             counter++;
             mtx.unlock();
         }
     }
};
int main()
{
     unsigned     int N = 7;
     boost::thread* test_threads = new thread_type[N];
     for(unsigned int i = 0; i<  N; i++)
     {
         test_threads[i] =
thread_type(boost::lambda::bind<void>(&Test::insert,&object));
     }
for(unsigned int i = 0; i<  N; i++)
     {
         test_threads[i].join();
     }
return 1;
}
***********************************************************************************************************************************
Can somebody shed some light? Main() exits normally, if I replace
mtx.try_lock() with mtx.lock(). Why this behavior?
You have to test the result of try_lock.  try_lock
doesn't block if the mutex is already locked, thus
your code can call unlock on a mutex that isn't locked.

In Christ,
Steven Watanabe