std::lock_guard

// lock_guard example
#include <iostream>       // std::cout
#include <thread>         // std::thread
#include <mutex>          // std::mutex, std::lock_guard
#include <stdexcept>      // std::logic_error
std::mutex mtx;
void print_even (int x) {
  if (x%2==0) std::cout << x << " is even\n";
  else throw (std::logic_error("not even"));
}
void print_thread_id (int id) {
  try {
    // using a local lock_guard to lock mtx guarantees unlocking on destruction / exception:
    std::lock_guard<std::mutex> lck (mtx);
    print_even(id);
  }
  catch (std::logic_error&) {
    std::cout << "[exception caught]\n";
  }
}
int main ()
{
  std::thread threads[10];
  // spawn 10 threads:
  for (int i=0; i<10; ++i)
    threads[i] = std::thread(print_thread_id,i+1);
  for (auto& th : threads) th.join();
  return 0;
}