不使用pthread_detach或pthread_join，是否不会为其他新创建的线程清除资源？

Question

Below is my code snippet.



int main ( )
    {
     some instructions;
     while ( 1 )
     {
       /* Block 1 : Starts*/
       if ( selection == 1 )
       {
         ret = pthread_create ( &tid, NULL, &select_n_process_req, NULL );
         if ( ret != 0 )
         {
           printf ("Error Creating Thread");
         }
       }
       /* Block 1 : Ends*/

       /* Block 2 : Starts*/
       printf ("Sleeping for [%d]", retry_time * 60 * 60);
       for ( i = 0; i < retry_time * 60 * 60; i++ )
       {
          if ( stop_flag == 1 )
          {
           printf ("Process Stopped\n");
           break;
          }
          sleep ( 1 );
       }
       /* Block 2 : ENDS*/
     }
     some instructions;
     return SUCCESS;
    }

    int select_n_process_req ( void )
    {
     some instructions;
     return SUCCESS;
    }

Explanation of the Code:

1. Block 1: The variable "selection" will always be 1 and the thread will be created always for doing some task.
2. Block 2: Once the thread is created, this blocks waits for "retry_time ( usually will 1 hour )" again to create a new thread for doing the same task.

Question:

1. I am not calling any pthread_join or pthread_detach, but I am returning(which will terminate the thread) from the function "select_n_process_req". Will this not clear the resources allocated to pthread_create?
2. I found it strange that after some load, pthread_create was not called at all. Is this because I am not using pthread_detach or pthread_join?

Thank You.

Answer 1

You have to either call pthread_join (from parent thread), or pthread_detach , or create the thread in detached state by passing additional attributes to pthread_create . See here: http://man7.org/linux/man-pages/man3/pthread_create.3.html