boost :: this_thread :: interruption_point()不会抛出boost :: thread_interrupted&exception

Question

我想使用boost :: thread interrupt()中断一个线程.我有以下代码,不会抛出boost :: thread_interrupted&exception:

int myClass::myFunction (arg1, arg2) try{
//some code here
    do {   
        boost::this_thread::interruption_point(); 
        //some other code here
    } while (counter != 20000); 
}catch (boost::thread_interrupted&) {
    cout << "interrupted" << endl;
}

如果我用boost :: this_thread :: sleep(boost :: posix_time :: milliseconds(150))替换boost :: this_thread :: interruption_point(),则抛出异常并且中断按预期工作.

有人可以解释为什么boost :: this_thread :: interruption_point()不会抛出预期的异常？

Answer 1

正如评论者指出的那样,没有办法排除简单的竞争条件(很大程度上取决于您的架构和CPU上的负载).添加明确睡眠"帮助"的事实强调了这一点.

你在单核系统上运行吗？

这是一个简单的自包含示例,以防您发现不同的事情.看到这个简单的测试者

#include <iostream> 
#include <boost/thread.hpp>

struct myClass { 
    int myFunction(int arg1, int arg2);
};

int myClass::myFunction (int arg1, int arg2)
{
    int counter = 0;
    try
    {
        //some code here
        do {   
            boost::this_thread::interruption_point(); 
            //some other code here
            ++counter;
        } while (counter != 20000); 
    } catch (boost::thread_interrupted&) {
        std::cout << "interrupted" << std::endl;
    }
    return counter;
}

void treadf() {
    myClass x;
    std::cout << "Returned: " << x.myFunction(1,2) << "\n";
}

int main()
{
    boost::thread t(treadf);
    //t.interrupt(); // UNCOMMENT THIS LINE
    t.join();
}

它打印

Returned: 20000

或者,如果您取消注释该行 t.interrupt()

interrupted
Returned: 0

在我的i7系统上.看到Live On Coliru