Please see my updates at the end of the answer, the situation has dramatically changed since Visual Studio 2015. The original answer is below. I made a very simple test and according to my measurements the std::mutex is around 50-70x slower than CRITICAL_SECTION. std::mutex: 18140574us CRITICAL_SECTION: 296874us Edit: After some more tests it turned out … Read more
It is both complicated and differs from Unix to Unix variant. In Linux, for example, a system called Futex (Short for Fast Userspace Mutex) is used. In this system an atomic increment and test operation is performed on the mutex variable in user space. If the result of the operation indicates that there was no … Read more
It is possible but not necessarily simple: the problem you are trying to solve is dangerously close to setting up a distributed development environment which is not exactly what SVN is designed for. The SVN-mirror way You can use svn mirror as explained in the SVN book documentation to create a read-only mirror of your … Read more
I got a modal Dialog while using: setCancelable(false); on the DialogFragment (not on the DialogBuilder).
That’s pretty easy: class Sample { private String message = null; private final Object lock = new Object(); public void newMessage(String x) { synchronized (lock) { message = x; } } public String getMessage() { synchronized (lock) { String temp = message; message = null; return temp; } } } Note that I didn’t either … Read more
Stick to pthread_cond_timedwait and use clock_gettime. For example: struct timespec ts; clock_gettime(CLOCK_REALTIME, &ts); ts.tv_sec += 10; // ten seconds while (!some_condition && ret == 0) ret = pthread_cond_timedwait(&cond, &mutex, &ts); Wrap it in a function if you wish. UPDATE: complementing the answer based on our comments. POSIX doesn’t have a single API to wait for … Read more
Synchronizing the run() method of a Runnable is completely pointless unless you want to share the Runnable among multiple threads and you want to sequentialize the execution of those threads. Which is basically a contradiction in terms. There is in theory another much more complicated scenario in which you might want to synchronize the run() … Read more
Even though you can use them in the way you describe, mutexes weren’t designed for use as a notification/synchronization mechanism. They are meant to provide mutually exclusive access to a shared resource. Using mutexes to signal a condition is awkward and I suppose would look something like this (where Thread1 is signaled by Thread2): Thread1: … Read more
You’ll need to write your own class to do this, I found this example (pasted because it looks as though the site’s domain has lapsed): using System.Threading; public sealed class QueuedLock { private object innerLock; private volatile int ticketsCount = 0; private volatile int ticketToRide = 1; public QueuedLock() { innerLock = new Object(); } … Read more
At first glance I thought I recognized this answer as the same algorithm that Alexander Terekhov introduced. But after studying it I believe that it is flawed. It is possible for two writers to simultaneously wait on m_exclusive_cond. When one of those writers wakes and obtains the exclusive lock, it will set exclusive_waiting_blocked = false … Read more