boost scoped unlock for a mutex

Question

I have a code that looks like:

boost::mutex::scoped_lock lck(mQueueMutex);

while (true)
{
    ...

    // unlock the queue while we exec the job
    lck.unlock();

    ...

    // lock the queue again
    lck.lock();
}

I am looking to do something like this:

boost::mutex::scoped_lock lock(mQueueMutex);

while (true)
{
    ...

    // unlock the queue while we exec the job
    {
        boost::mutex::scoped_unlock unlock(lock);

        ...
    }

}

I am almost sure that I have seen this before ... or at least discussion about it, but I can't find it.

Answer 1

You are looking for Boost.Threads Reverse Lock :

reverse_lock reverse the operations of a lock: it provide for RAII-style, that unlocks the lock at construction time and lock it at destruction time. In addition, it transfer ownership temporarily, so that the mutex can not be locked using the Lock.