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

int main() {
  boost::try_mutex myMutex;
  boost::try_mutex::scoped_lock lock1(myMutex);
  try {
    boost::try_mutex::scoped_try_lock lock2(myMutex);
  } catch(boost::lock_error) {
    std::cout << "Was locked already" << std::endl;
  }
}