（1） wait(lock): 呼叫時即阻塞執行緒，並且呼叫lock.unlock()
（2） wait(lock, conditions): 呼叫時檢查conditions，如果為false,則阻塞執行緒，並且呼叫lock.unlock(), 否則，繼續執行、
（3） wait_for(lock, time_duration, conditions): 呼叫時，檢查條件是否滿足:(1) conditions返回true; (2) 時間超時，如果不滿足(1)(2)中的乙個條件，則阻塞執行緒，並呼叫lock.unlock(), 否則，到達一定等待時間或滿足條件被喚醒 ，注意，等待超過時間段後自動喚醒，判斷條件一般需要使用者自己在合適的時候判斷，並通過notify_one()或notify_all()喚醒，所以，使用的時候注意判斷返回值，即狀態是否為std::cv_status::timeout
（4） wait_until(lock, time_point, conditions): 實際wait_for是通過wait_until實現，實際上也是一樣的，到達指定時間點或滿足條件conditions時被喚醒，注意，到達時間點是自動喚醒，判斷條件一般需要使用者自己在合適的時候判斷，並通過notify_one()或notify_all()喚醒，所以，使用的時候注意判斷返回值，即狀態是否為std::cv_status::timeout
#include #include #include #include #include using namespace std;
static std::mutex mtx;
static bool ready = false;
static std::condition_variable ***;
static int block_time = 20;
void run_thread(int i)
#else
std::cout << __function__ << ": run here wait start i = " << i << std::endl;
***.wait(lg, ); // 如果條件滿足，則執行，否則，直接阻塞，釋放鎖
std::cout << __function__ << ": run here wait i = " << i << std::endl;
#endif
std::cout << __function__ << ": run here ready i = " << i << std::endl;
}void run_thread2(int i)
); // 如果條件滿足，則執行，否則，直接阻塞，釋放鎖
std::cout << __function__ << ": run here wait i = " << i << ", ready = " << ready << ", currenttime = " << std::chrono::time_point_cast(std::chrono::system_clock::now()).time_since_epoch().count() << std::endl;
std::cout << __function__ << ": run here ready i = " << i << ", ready = " << ready << ", currenttime = " << std::chrono::time_point_cast(std::chrono::system_clock::now()).time_since_epoch().count() << std::endl;
}void run_thread3(int i)
); // 如果條件滿足，則執行，否則，直接阻塞，釋放鎖
std::cout << __function__ << ": run here wait i = " << i << ", ready = " << ready << ", currenttime = " << std::chrono::time_point_cast(std::chrono::system_clock::now()).time_since_epoch().count() << std::endl;
std::cout << __function__ << ": run here ready i = " << i << ", ready = " << ready << ", currenttime = " << std::chrono::time_point_cast(std::chrono::system_clock::now()).time_since_epoch().count() << std::endl;
}void run_go()
int main()
std::cout << "currenttime b = " << std::chrono::time_point_cast(std::chrono::system_clock::now()).time_since_epoch().count() << std::endl;
std::cout << "run here create thread end" << std::endl;
std::this_thread::sleep_for(std::chrono::seconds(block_time));
std::cout << "run here create thread wait " << std::endl;
std::cout << "currenttime c = " << std::chrono::time_point_cast(std::chrono::system_clock::now()).time_since_epoch().count() << std::endl;
// run_go();
for(int i = 0; i < 10; ++i)
}std::cout << "***************= case 2 end ***************=" << std::endl;
}std::cout << "currenttime b = " << std::chrono::time_point_cast(std::chrono::system_clock::now()).time_since_epoch().count() << std::endl;
std::cout << "run here create thread end" << std::endl;
std::this_thread::sleep_for(std::chrono::seconds(block_time));
std::cout << "run here create thread wait " << std::endl;
std::cout << "currenttime c = " << std::chrono::time_point_cast(std::chrono::system_clock::now()).time_since_epoch().count() << std::endl;
// // run_go();
for(int i = 0; i < 10; ++i)
}std::cout << "***************= case 3 end ***************=" << std::endl;
}std::cout << "run here create thread end" << std::endl;
std::this_thread::sleep_for(std::chrono::seconds(block_time));
std::cout << "run here create thread wait " << std::endl;
run_go();
for(int i = 0; i < 10; ++i)
}std::cout << "***************= case 1 end ***************=" << std::endl;
}return 0;
}
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