blocked in message_queue::timed_receive

[liuaifu]

I'm using boost_1_89_0 & boost::interprocess::message_queue for inter-process communication. The receiver calls timed_receive to receive messages with a timeout set to 100 milliseconds. It works correctly most of the time, but occasionally it gets blocked, meaning timed_receive does not return.

boost::interprocess::message_queue *msg_queue;
// ...
boost::posix_time::ptime timeout = boost::posix_time::microsec_clock::universal_time() + boost::posix_time::milliseconds(100);
bool ret = msg_queue->timed_receive(buf, 8192, recvd_size, priority, timeout);

I checked the call stack, and it is blocked at the following location:

boost\interprocess\sync\detail\common_algorithms.hpp

template<class MutexType>
void try_based_lock(MutexType &m)
{boost::interprocess::message_queue
   if(!m.try_lock()){
      spin_wait swait;
      do{
         if(m.try_lock()){
            break;
         }
         else{
            swait.yield();
         }
      }
      while(1);
   }
}

I stepped through the code and found that m.try_lock() keeps returning false.

Thanks.