源代码（引用文档中例子）：
1 #include <iostream>
2 #include <chrono>
3 #include <thread>
4 #include <mutex>
5 #include <map>
6 #include <string>
7
8 std::map<std::string, std::string> g_pages;
9 std::mutex g_pages_mutex;
10
11 void save_page(const std::string &url)
12 {
13 // simulate a long page fetch
14 std::this_thread::sleep_for(std::chrono::seconds(2));
15 std::string result = "fake content";
16
17 g_pages_mutex.lock();
18 g_pages[url] = result;
19 g_pages_mutex.unlock();
20 }
21
22 int main()
23 {
24 std::thread t1(save_page, "http://foo");
25 std::thread t2(save_page, "http://bar");
26 t1.join();
27 t2.join();
28
29 g_pages_mutex.lock();
30 for (const auto &pair : g_pages) {
31 std::cout << pair.first << " => " << pair.second << '\n';
32 }
33 g_pages_mutex.unlock();
34 }
编译命令： 当使用C++11时，需要指定 -std=c++11，-pthread,-D_GLIBCXX_USE_NANOSLEEP三项，缺一不可。
g++ mutex.cpp -o mutex -std=c++11 -pthread -D_GLIBCXX_USE_NANOSLEEP
错误情况：
1.指定-std=c++11:
[root@localhost test]# g++ mutex.cpp -o mutex -std=c++11
mutex.cpp: In function ‘void save_page(const string&)’:
mutex.cpp:12:2: error: ‘sleep_for’ is not a member of ‘std::this_thread’
在命令中指定_GLIBCXX_USE_NANOSLEEP：
g++ mutex.cpp -o mutex -std=c++11 -D_GLIBCXX_USE_NANOSLEEP
The define _GLIBCXX_USE_NANOSLEEP is set from the gcc configuration scripts and is based on whether nanosleep is supported on the target platform.
2.当额外添加-c参数时，生成的执行文件为非执行的。手动修改为执行文件，执行时出错！！
g++ -c mutex.cpp -o mutex -std=c++11 -D_GLIBCXX_USE_NANOSLEEP
3.未指定-pthread:
g++ mutex.cpp -o mutex -std=c++11 -D_GLIBCXX_USE_NANOSLEEP
生成可执行文件mutex，执行此文件时报错：
[root@localhost test]# ./mutex
terminate called after throwing an instance of 'std::system_error'
what(): Operation not permitted
Aborted
