std::condition_variable

• std::condition_variable::wait

• https://en.cppreference.com/w/cpp/thread/condition_variable/wait

  • 解除 mutex

  • 暫停 thread

  • 等待 notify 再次拿到 mutex, 繼續 thread

• condition_variable wait

  • wait: unlock mutex, block thread

  • notify (喚醒): unblock thread

  • reaquire lock (next wait), wait exits