#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <pthread.h>

void* aworking(void* arg);

struct Test{
    int num;
    int age;
};

int main(int argc, char const *argv[])
{

    struct Test t;

    pthread_t apid;
    pthread_create(&apid, NULL, aworking, &t);
    // pthread_join是一个阻塞函数，需等到子线程执行结束后才能解除阻塞
    // 并能接受子线程调用pthread_exit传递的参数
    void* ptr;
    // pthread_join的第二个参数是一个二级指针，即指向内存空间指针的指针
    pthread_join(apid, &ptr);

    struct Test* pt = (struct Test*)ptr;
    printf("sub thread - num: %d, age: %d\n", pt->num, pt->age);

    for (size_t i = 0; i < 10; i++)
    {
        printf("this is main thread......1, thread id: %ld\n", pthread_self());
    }

    return 0;
}

void* aworking(void* arg){

    int num = 0;
    for (size_t i = 0; i < 10; i++)
    {
        printf("this is aworking thread......%d, thread id: %ld\n", num++, pthread_self());
    }

    // 如果不把Test结构体定义成静态变量或者全局变量，那么当子线程释放后，子线程的栈空间也被释放了，数据就清除了。
    //static struct Test t;
    // 或者在使用主线程的栈空间传递数据到子线程
    struct Test* t = (struct Test*)arg;
    t->num = 100;
    t->age = 6;
    // 子线程携带数据退出
    pthread_exit(t);
    return NULL;
}