Question

If I do:

ConsoleApp1:

    bool mutexCreated;
    var mutex = new Mutex(true, "MemoryMappedFileMutex", out mutexCreated);

    Console.Write("Run Console App2 then press enter");
    Console.Read();

    // do work
    Thread.Sleep(5000);

    mutex.ReleaseMutex(); // makes console app 2 to stop waiting

ConsoleApp2

    var mutex = Mutex.OpenExisting("MemoryMappedFileMutex");

    mutex.WaitOne();

    // continue executing once console app 1 releases mutex

Everything works great. I have to start consoleApp1 first for this algorithm to work though.

Now my qestion is I will like consoleApp2 to act as the server. Therefore I will like to start that application first. The problem is that if I do:

    bool mutexCreated;
    var mutex = new Mutex(true, "MemoryMappedFileMutex", out mutexCreated);

    mutex.WaitOne();  // <------ mutex will not wait why????

if I do mutex.WaitOne() that thread will not wait. In other words I want to start consoleApp2 first and have that application wait until I signal the mutex somehow on console application 1….

Answer 1

In your server app, try calling the constructor with false as the first parameter, so that the calling thread will not own the mutex initially.