Linux pthread_exit()传递线程返回码

（1）通过全局变量进行传递

struct food
{
    int a;
    int b;
    int c;
};
struct food apple;

void* task1(void* arg)
{
    apple.a = 27;
    apple.b = 12;
    apple.c = 39;
    pthread_exit((void*)&apple);
}

int main(int argc, char *argv[])
{
    pthread_t thrd1, thrd2, thrd3;
    void* tret;

    pthread_create(&thrd1, NULL, (void*)task1, NULL);
    pthread_join(thrd1, (void*)&tret);

　　 printf("The food:%d %d %d\n", ((struct food*)(tret))->a, ((struct food*)(tret))->b, ((struct food*)(tret))->c);
    printf("Main thread exit...\n");

    return 0;
}

 程序输出：

[root@robot ~]# gcc thread_exit.c -lpthread -o thread_exit
[root@robot ~]# ./thread_exit
The food:27 12 39
Main thread exit...
[root@robot ~]#

（2）通过malloc分配变量进行传递

struct food
{
    int a;
    int b;
    int c;
};

void* task1(void* arg)
{
    struct food *apple = malloc(sizeof(struct food));
    apple->a = 23;
    apple->b = 82;
    apple->c = 59;
    pthread_exit((void*)apple);
}

int main(int argc, char *argv[])
{
    pthread_t thrd1, thrd2, thrd3;
    void* tret;

    pthread_create(&thrd1, NULL, (void*)task1, NULL);
    pthread_join(thrd1, (void*)&tret);

    printf("The food:%d %d %d\n", ((struct food*)(tret))->a, ((struct food*)(tret))->b, ((struct food*)(tret))->c);
    free(((struct food*)tret));
    printf("Main thread exit...\n");

    return 0;
}

 程序输出：

[root@robot ~]# gcc thread_exit.c -lpthread -o thread_exit
[root@robot ~]# ./thread_exit
The food:23 82 59
Main thread exit...
[root@robot ~]#