How to make main thread wait for all child threads finish?

Question

I intend to fire 2 threads in the main thread, and the main thread should wait till all the 2 child threads finish, this is how I do it.

void *routine(void *         


        

Answer 1

First create all the threads, then join all of them:

pthread_t tid[2];

/// create all threads
for (int i = 0; i < 2; i++) {
    pthread_create(&tid[i], NULL, routine, NULL);
}

/// wait all threads by joining them
for (int i = 0; i < 2; i++) {
    pthread_join(tid[i], NULL);  
}

Alternatively, have some pthread_attr_t variable, use pthread_attr_init(3) then pthread_attr_setdetachedstate(3) on it, then pass its address to pthread_create(3) second argument. Thos would create the threads in detached state. Or use pthread_detach as explained in Jxh's answer.