Rejoining threads in C

In my main function, I spawn j threads which 开发者_运维技巧all compute the same task in parallel -- and then I want to wait for them to finish before exiting.

int main(...) {

    // ...

    int threads = 6;
    pthread_t* thread = malloc(sizeof(pthread_t)*threads);

    for(i = 0; i < threads; i++) {

        struct thread_param *tp;
        tp = malloc(sizeof(*tp));

        // ... 

        int ret = pthread_create(&thread[i], NULL, &control, (void*)tp);

        if(ret != 0) {
            printf ("Create pthread error!\n");
            exit (1);
        }
    }

    for (j = 0; j < threads; j++) {
        printf("JOINING THREAD: %i\n", j);
        pthread_join( &thread[j], NULL);
    }        

    exit(0);
}

However, nothing waits. Main just exits without ever completing the threaded tasks. Am I missing something?

hey, try pthread_join( thread[j], NULL); i think the problem is with types. I checked docs:

int pthread_join(pthread_t thread, void **value_ptr);

and thread is p_thread*, and thread[j] is p_thread, while &thread[j] is p_thread*, which is invalid. There just might internal error happen.

Edit: Yeah, I am very positive with that, pthread_t is basically int, so pthread_t* is accepted, it is just invalid thread handle, so pthread_join fails internally.