| 1 | // Copyright (C) 2001-2003 |
|---|---|
| 2 | // William E. Kempf |
| 3 | // |
| 4 | // Distributed under the Boost Software License, Version 1.0. (See accompanying |
| 5 | // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| 6 | |
| 7 | #define BOOST_THREAD_PROVIDES_ONCE_CXX11 |
| 8 | |
| 9 | #include <boost/thread/thread.hpp> |
| 10 | #include <boost/thread/once.hpp> |
| 11 | #include <cassert> |
| 12 | |
| 13 | int value=0; |
| 14 | #ifdef BOOST_THREAD_PROVIDES_ONCE_CXX11 |
| 15 | static boost::once_flag once; |
| 16 | //static boost::once_flag once2 = BOOST_ONCE_INIT; |
| 17 | #else |
| 18 | static boost::once_flag once = BOOST_ONCE_INIT; |
| 19 | //static boost::once_flag once2 = once; |
| 20 | #endif |
| 21 | |
| 22 | void init() |
| 23 | { |
| 24 | ++value; |
| 25 | } |
| 26 | |
| 27 | void thread_proc() |
| 28 | { |
| 29 | boost::call_once(func: &init, flag&: once); |
| 30 | } |
| 31 | |
| 32 | int main() |
| 33 | { |
| 34 | boost::thread_group threads; |
| 35 | for (int i=0; i<5; ++i) |
| 36 | threads.create_thread(threadfunc: &thread_proc); |
| 37 | threads.join_all(); |
| 38 | assert(value == 1); |
| 39 | } |
| 40 |