c++ - 信号系统调用可以与类的 C++ 静态成员一起使用吗？

Question

*nix 平台是否支持以下内容？

    #include <cstdio>
    #include <sys/types.h>
    #include <signal.h>
    #include <unistd.h>

    class SignalProcessor
    {
     public:
      static void OnMySignal(int sig_num)
      {
          printf("Caught %d signal\n", sig_num);
          fflush(stdout);

          return;
      } 
    }; 
    using namespace std;

   int main()
   {

          signal(SIGINT,SingalProcessor::OnMySignal);
          printf("Ouch\n");

          pause();

          return 0;
   }

Answer 1

从技术上讲不，你不能。

您碰巧很幸运，您的编译器使用与“C”函数相同的调用约定。由于未定义 C++ ABI，下一个版本的编译器可以自由使用完全不同的调用约定，这会在编译器没有警告的情况下扰乱您的代码。

参见:http://www.parashift.com/c++-faq-lite/pointers-to-members.html#faq-33.2
请参阅本节末尾的注释

Note: static member functions do not require an actual object to be invoked, so pointers-to-static-member-functions are usually type-compatible with regular pointers-to-functions. However, although it probably works on most compilers, it actually would have to be an extern "C" non-member function to be correct, since "C linkage" doesn't only cover things like name mangling, but also calling conventions, which might be different between C and C++.

编辑:
回答 Sasha 的评论:

以线程为例:

#include <iostream>
class Thread
{    public:   virtual void run()  = 0; };

extern "C" void* startThrerad(void* data)
{
    Thread*  thread = reinterpret_cast<Thread*>(data);
    try
    {
        thread->run();
    }
    catch(...)
    {    /* Log if required. Don't let thread exit with exception. */ }
    return NULL;
}
class MyJob: public Thread
{
    public: virtual void run() {std::cout << "HI\n";}
};
int main()
{
    MyJob     job; // MyJob inherits from Thread
    pthread_t th;

    // In most situation you do not need to dynamic cast.
    // But if you use multiple inheritance then things may get
    // interesting, as such best to always use it.
    pthread_create(&th,NULL,startThrerad,dynamic_cast<Thread*>(&job));

    void*     result;
    pthread_join(th,&result);
}