C++多线程编程（一）

转自：http://www.bogotobogo.com/cplusplus/C11/6_C11_Thread_with_Move_Semantics.php

Thread with Move Semantics

#include
#include
#include
#include
#include
using namespace std;


void task(int i) {
	cout << "workers " << i << endl;
}


int main() {

	vector workers;

	for (int i = 0; i < 5; i++)
	{
	/*	auto t = thread([i]() {

			cout << "thread function" <

Sharing resources

//http://www.bogotobogo.com/cplusplus/C11/7_C11_Thread_Sharing_Memory.php
#include
#include
#include
#include
using namespace std;

/*

This seemingly innocent short code has already an issue of
race condition for a resource, cout.:

*/

mutex mu;
void share_function(string s,int id) {
	mu.lock();
	cout << s<< " "<

Mutexes

lock()、unlock()、lock_guard()

In C++, we create a mutex by constructing an instance of std::mutex, lock it with a call to the member function lock(), and unlock it with a call to the member function unlock(). However, it is not a good practice to call the member functions directly, because this means that we have to remember to call unlock() on every code path out of a function, including those due to exceptions.

In other words, if we have an exception in the code after the lock() but before the unlock(), then we'll have a problem. The resources are in locked state!

So, the Standard C++ Library provides the std::lock_guard class template, which implements that RAII idiom for a mutex. It locks the supplied mutex on construction and unlocks it on destruction, thus ensuring a locked mutex is always correctly unlocked.

The example below shows how to protect a list that can be accessed by multiple threads using a std::mutex, along with std::lock_guard. Both of these are declared in the  header.

std::lock_guard 与mutex配合使用，把锁放到lock_guard中时，mutex自动上锁，lock_guard析构时，同时把mutex解锁。

#include
#include
#include
#include
#include

using namespace std;

list MyList;

mutex myMutex;

const int MAX = 100;
void addToList(int interval,int id) {
	
	//对这个函数的访问是互斥的
	lock_guard guard(myMutex);
	for (int i = 0; i < MAX; i++){
		if (i%interval == 0)
			MyList.push_back(i);
	}
	cout << "thread " << id << "runing..........." << endl;
}
void PrintList() {

    //对这个函数的访问是互斥的
	lock_guard guard(myMutex);
	for (auto it = MyList.begin(); it != MyList.end(); it++) {
		cout << *it << ","<