VB.Net Tutorial/Thread/Mutex

Global Mutex

Imports System.Threading
Module Module1
    Public Class MutexSample
        Shared globalMutex1 As Mutex
        Shared globalMutex2 As Mutex
        Const Counter As Integer = 100
        Shared Event1 As AutoResetEvent = New AutoResetEvent(False)
        Shared Event2 As AutoResetEvent = New AutoResetEvent(False)
        Shared Event3 As AutoResetEvent = New AutoResetEvent(False)
        Shared Event4 As AutoResetEvent = New AutoResetEvent(False)
        Public Sub do1()
            Console.WriteLine("do1 started,  Mutex.WaitAll(Mutex())")
            Dim gMs(1) As Mutex
            gMs(0) = globalMutex1    
            gMs(1) = globalMutex2
            WaitHandle.WaitAll(gMs)
            Thread.Sleep(2000)
            Console.WriteLine("do1 finished, Mutex.WaitAll(Mutex())")
            Event1.Set()
        End Sub
        Public Sub do2()
            Console.WriteLine("do2 started,  globalMutex1.WaitOne( )")
            globalMutex1.WaitOne()   
            Console.WriteLine("do2 finished, globalMutex1.WaitOne( )")
            Event2.Set()  
        End Sub
        Public Sub do3()
            Console.WriteLine("do3 started,  Mutex.WaitAny(Mutex())")
            Dim gMs(1) As Mutex
            gMs(0) = globalMutex1    
            gMs(1) = globalMutex2
            Mutex.WaitAny(gMs)
            Console.WriteLine("do3 finished, Mutex.WaitAny(Mutex())")
            Event3.Set()     
        End Sub
        Public Sub do4() 
            Console.WriteLine("do4 started,  globalMutex2.WaitOne( )")
            globalMutex2.WaitOne()    
            Console.WriteLine("do4 finished, globalMutex2.WaitOne( )")
            Event4.Set()     
        End Sub
        Public Sub Run()     
            Console.WriteLine("MutexSample ...")
            globalMutex1 = New Mutex(True, "MyMutex") 
            globalMutex2 = New Mutex(True)   
            Console.WriteLine(" - Main Owns globalMutex1 and globalMutex2")
            Dim evs(3) As AutoResetEvent
            evs(0) = Event1   
            evs(1) = Event2   
            evs(2) = Event3   
            evs(3) = Event4   
            Dim tm As MutexSample = New MutexSample()
            Dim t1 As Thread = New Thread(New ThreadStart(AddressOf tm.do1))
            Dim t2 As Thread = New Thread(New ThreadStart(AddressOf tm.do2))
            Dim t3 As Thread = New Thread(New ThreadStart(AddressOf tm.do3))
            Dim t4 As Thread = New Thread(New ThreadStart(AddressOf tm.do4))
            t1.Start()     
            t2.Start()     
            t3.Start()     
            t4.Start()     
            Thread.Sleep(2000)
            Console.WriteLine(" - Main releases globalMutex1")
            globalMutex1.ReleaseMutex() 
            Thread.Sleep(1000)
            Console.WriteLine(" - Main releases globalMutex2")
            globalMutex2.ReleaseMutex() 
        End Sub
    End Class 
    Sub main()
        Dim ms As MutexSample = New MutexSample()
        ms.Run()
    End Sub
End Module

MutexSample ...
 - Main Owns globalMutex1 and globalMutex2
do1 started,  Mutex.WaitAll(Mutex())
do2 started,  globalMutex1.WaitOne( )
do3 started,  Mutex.WaitAny(Mutex())
do4 started,  globalMutex2.WaitOne( )
 - Main releases globalMutex1
do3 finished, Mutex.WaitAny(Mutex())
^CTerminate batch job (Y/N)? n