Single Instance Application

Single instance application can be implemented using Mutex. Mutex is a synchronizing object that can be used across processes. When the first instance of an application is created, we create a named mutex. In the following attempts we check if the named mutex is already created.

Using remoting, we can send command parameters to the first instance.

private static bool IsRunning()
{
     bool bCreatedNew;

     // Parameters to create Mutex object
     // 1. initiallyOwned = true
     // this gets the calling thread initial ownership of the mutex
     // 2. name of the mutex
     // 3. createdNew
     // When this method returns, contains a Boolean that is true
     // if the calling thread was granted initial ownership
     // of the mutex; otherwise, false.
     // This parameter is passed uninitialized.
     //
     _AppMutex = new Mutex(true, _MutexKey, out bCreatedNew);
     if (bCreatedNew)
          _AppMutex.ReleaseMutex();
     return !bCreatedNew;
}

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