c++ - 以安全的方式了解 pthread 线程是否处于事件状态

Question

我制作了一个连续生成/销毁 100 个线程的多线程应用程序:

//Here is the thread class (one by every thread
struct s_control
{
   data_in[D_BUFFER_SIZE];//data in to thread
   data_out[D_BUFFER_SIZE];//data generated by the thread
   //I use volatile in order to status data is avaiable in and out of the thread:
   volatile __int16 status;//thread state 0=empty,1=full,2=filling (thread running)
}*control;

//Here is the thread main function    
static void* F_pull(void* vv)//=pull_one_curl() 
{
   s_control* cc = (s_control* ) vv;
   //use of cc->data_in and filling of cc->data out      
   cc->status=1;  //Here advises that thread is finished and data out is filled
   return NULL;
}

void main()
{
   initialization();
   control=new s_control[D_TAREAS];
   pthread_t *tid=new pthread_t[D_TAREAS];
   for (th=0;th<D_TAREAS;th++)
   {  //Access to status of thread at the beginning 
      //(to avoid if it changes in the middle):
      long status1=control[th].status
      if (status1==0)            //Thread finished and data_out of thread is empty
      { control[i2].status=2;    //Filling in (thread initiated)status LLENANDO
        error = pthread_create(&tid[th],NULL,F_pull,(void *) &control[th]);
      }
      else if (status1==1) //Thread finished and data_out of thread is full
      {
         //do things with control[th].data_out;
         //and fill in control[th].data_in with data to pass to next thread
         control[th].status=0;    //Thread is finished and now its data_out is empty
      }
      else 
      {
        //printf("\nThread#%li:filling",i2);
      }
   }while(!_kbhit());
   finish();
}

然后如您所见，在线程结束时，我使用变量 volatile 来通知线程即将退出:

begin of thread{ ....
   cc->status=1;  //Here advises that thread is finished and data out is filled
   return NULL;
}//END OF THREAD

但是在cc->status设置为1之后，线程还没有结束(多了一行)

所以我不喜欢在线程内设置状态。我尝试了 pthread_kill，但它没有用，因为它在线程处于事件状态之前不起作用，如在以下位置所见: pthread_kill

Answer 1

我不确定这是否回答了您的问题，但是您可以使用 pthread_join() 来等待线程终止。结合一些(适当同步的)状态变量，您应该能够实现您所需要的。