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// Copyright (C) 2001-2003
// William E. Kempf
// Permission to use, copy, modify, distribute and sell this software
// and its documentation for any purpose is hereby granted without fee,
// provided that the above copyright notice appear in all copies and
// that both that copyright notice and this permission notice appear
// in supporting documentation.  William E. Kempf makes no representations
// about the suitability of this software for any purpose.
// It is provided "as is" without express or implied warranty.

#include <boost/thread/thread.hpp>
#include <boost/thread/once.hpp>
#include <cassert>

int value=0;
boost::once_flag once = BOOST_ONCE_INIT;

void init()

void thread_proc()
    boost::call_once(&init, once);

int main(int argc, char* argv[])
    boost::thread_group threads;
    for (int i=0; i<5; ++i)
    assert(value == 1);