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

boost::mutex io_mutex;
boost::thread_specific_ptr<int> ptr;

struct count
{
  count(int id) : id(id) { }

  void operator()()
  {
    if (ptr.get() == 0)
      ptr.reset(new int(0));

    for (int i = 0; i < 10; ++i)
    {
      (*ptr)++;
      boost::mutex::scoped_lock
        lock(io_mutex);
      std::cout << id << ": "
        << *ptr << std::endl;
    }
  }

  int id;
};

int main(int argc, char*
 argv[])
{
  boost::thread thrd1(count(1));
  boost::thread thrd2(count(2));
  thrd1.join();
  thrd2.join();
  return 0;
}