C++语法小记---自己实现Thread类

自己实现Thread类

• 在C++的类中，普通成员函数不能作为pthread_create的线程函数，如果要作为pthread_create中的线程函数，必须是static !

• 参考：https://blog.csdn.net/ksn13/article/details/40538083

 //方式1：使用类的static函数做转换，配合this指针
 class Thread
 {
 private:
     pthread_t id;

     static void * start_thread(void *arg)
     {
         Thread* thread = (Thread*)arg;
         thread->run();
     }

 public:

     virtual void run()
     {
         cout << "success" <<endl;
     }

     virtual void start()
     {
         pthread_create(&id, NULL, start_thread, (void *)this);//传入this指针是关键
     }
 }; 

 class MyThead: public Thread
 {
 public:
     virtual void run()
     {
         cout << "MyThead::run()" << endl;
     }
 };

 int main()
 {
     MyThead t;
     t.start();

     sleep();

     return ;
 }

 //方式2：直接使用强制类型转换，因为this->xxx() 本质上等同于 xxx(this)
 //方式2比当时1更安全，因为没有使用static
 class Thread
 {
 private:
     pthread_t id;

     void* threadFunc(void* arg)
     {
         this->run();
     }

 public:

     typedef void* (*FUNC)(void*);

     virtual void run()
     {
         cout << "success" <<endl;
     }

     virtual void start()
     {
         FUNC callback = (FUNC)&Thread::threadFunc;
         pthread_create(&id, NULL, callback, this); //此处传入this是必须的，且在callback中arg不可用，因为为NULL
     }
 }; 

 class MyThead1: public Thread
 {
 public:
     virtual void run()
     {
         sleep();
         cout << "MyThead1::run()" << endl;

     }
 };

 class MyThead2: public Thread
 {
 public:
     virtual void run()
     {
         cout << "MyThead2::run()" << endl;
     }
 };

 int main()
 {
     MyThead1 t1;
     t1.start();

     MyThead2 t2;
     t2.start();

     sleep();

     return ;
 }