condition-variable.md

Condition Variable

• std::condition_variable is a standard library synchronization primitive introduced in C++11. It implements the condition variable mechanism — an important multithreaded synchronization primitive that allows threads to wait until a specific condition is met, at which point other threads can notify the waiting threads to recheck the condition.
• notify_one() is a core member function of std::condition_variable, used to wake up one thread waiting on the condition variable.

notify_one() is used for task distribution, ensuring each task is processed by only one worker thread, while notify_all() is used for shutdown signals, ensuring all threads receive the exit notification.

• unique_lock is a flexible and powerful mutex wrapper introduced in C++11 — a movable but non-copyable RAII-style lock manager.

Note: unique_lock works with condition variables (this is a key difference from lock_guard).

• wait is the core member function of std::condition_variable, used to make a thread wait for a certain condition to become true.