共享信号量类似于 读写锁
boost::shared_mutex shr_mutex;
void write_process() {
shr_mutex.lock(); cout << "begin of write_process" << endl; cout << "end of write_process" << endl; shr_mutex.unlock();
}
void read_process() { shr_mutex.lock_shared(); cout << "begin of read_process" << endl; cout << "end of read_process" << endl; shr_mutex.unlock_shared();}int main() { thread_group threads;
for (int i = 0; i < 10; ++ i) { threads.create_thread(&write_process); threads.create_thread(&read_process);
} threads.join_all();