c++ - How to use lock_guard in this conditional -

a thread has following control flow:

mutex.lock() if (condition) {     // synced things     mutex.unlock();     // parallel things } else {     // other synced things     mutex.unlock();     // other parallel things } 

note how 4 do parts execute different things.

how replace direct calls lock , unlock using std::lock_guard instead?

std::unique_lock looks you're looking for. semantics similar std::lock_guard, allows more sophisticated constructs. in case still exception safety, can explicitly unlock early. like:

std::unique_lock<decltype(mutex)> guard(mutex); // calls mutex.lock() lock_guard if (condition) {     // synced things     guard.unlock();     // parallel things } else {     // other synced things     guard.unlock();     // other parallel things } // unlocks on leaving scope, if held similar lock_guard