c++11的mutex unique_lock和lock_guard區別
阿新 • • 發佈：2019-02-13
區域鎖lock_guard使用起來比較簡單，除了建構函式外沒有其他member function，在整個區域都有效。
區域鎖unique_guard除了lock_guard的功能外，提供了更多的member_function，相對來說更靈活一些。
unique_guard的最有用的一組函式為：
| lock |
locks the associated mutex (public member function) |
|
tries to lock the associated mutex, returns if the mutex is not available (public member function) |
|
attempts to lock the associated TimedLockable mutex,
returns if the mutex has been unavailable for the specified time duration (public member function) |
|
tries to lock the associated TimedLockable mutex,
returns if the mutex has been unavailable until specified time point has been reached (public member function) |
|
| unlocks the associated mutex |
通過上面的函式，可以通過lock/unlock可以比較靈活的控制鎖的範圍，減小鎖的粒度。
通過try_lock_for/try_lock_until則可以控制加鎖的等待時間，此時這種鎖為樂觀鎖。
以上為粗淺理解，後面有新的心得在補充之。