core.dll function CreateMutexW, One Instance of Application

[jakubbukaj]

Good Day,
I found link
http://www.gotdotnet.com/Community/...mpleGuid=9a07ca83-0fd2-44b7-82d0-bd3cfa84e294

Now I can support only one instance of my Application. In example is used function CreateMutexW from imported core.dll. In example code is creating mutex but it is never destroyed. So I dont do this (mutex will be destroyed after end of application automaticly) or it is destroyed.... someday?

Can somebody help me how to find out which functions are in Core.dll and how to use them? Some good link?

Thanks a lot