When you build applications for Windows, there are many reasons why you would want to restrict users from launching multiple instances of your application. Some common examples are installers, uninstallers, update utilities, media applications, utility tools, and so on.
In a normal application, when you launch the app, it creates a Windows process, and allocates its own memory space and resources. But, when you don't want to create multiple instances of the process for a single application that is already running, you want to silently quit the new instance and bring the running process into the foreground.
In this recipe, we will learn how to achieve this using Mutex (Mutual Exclusion) and unmanaged code.
