SuperStrict
Import MaxGui.Drivers

Global Mutex:Int

OnEnd ReleaseInstance
If InitSingleInstance("Prog1") Then DebugLog "ok" Else Notify "Prog1 laeuft schon!";End


Local Window1:TGadget = CreateWindow:TGadget("Window1",357,138,236,143,Null,WINDOW_TITLEBAR|WINDOW_RESIZABLE |WINDOW_STATUS |WINDOW_CLIENTCOORDS )
   Local Ende:TGadget = CreateButton:TGadget("End",75,48,75,23,Window1:TGadget,BUTTON_PUSH)

Repeat
   WaitEvent()
   Select EventID()
      Case EVENT_WINDOWCLOSE
         Select EventSource()
            Case Window1   Window1_WC( Window1:TGadget )
         End Select

      Case EVENT_GADGETACTION
         Select EventSource()
            Case Ende   Ende_GA( Ende:TGadget )
         End Select

   End Select
Forever

Function Window1_WC( Window:TGadget )
   DebugLog "Window Window1 wants to be closed"
'   HideGadget( Window:TGadget )

   End
End Function

Function Ende_GA( Button:TGadget )
   DebugLog "Button End was pressed"
   End
End Function

Function InitSingleInstance:Int( name:String)
   DebugLog "Create singele instance"
?Win32
   Extern "Win32"
      Const ERROR_ALREADY_EXISTS:Int = 183
      
      Function CreateMutexW:Int( security:Byte Ptr, owner:Int, name$w)
      Function GetLastError:Int()
   EndExtern
   
   Mutex = CreateMutexW( Null, True, name)
   If (Not Mutex) Or (GetLastError() = ERROR_ALREADY_EXISTS) Then Return False
?
   Return True
EndFunction

Function ReleaseInstance()
   DebugLog "Release Mutex"
   Extern "Win32"
      Function ReleaseMutex:Int( mutex:Int)
   EndExtern
   
   If Mutex Then
      ReleaseMutex( Mutex)
      Mutex = 0
   EndIf
EndFunction