Public Class Form1
 
    Dim fs As IO.FileStream
    Dim sw As IO.StreamWriter
 
    Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        sw.Close()
    End Sub
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        If IO.File.Exists("F:Test\share.txt") Then
            IO.File.Delete("F:Test\share.txt")
        End If
        fs = New IO.FileStream("F:Test\share.txt", IO.FileMode.Create, _
          IO.FileAccess.Write, IO.FileShare.Read)
        sw = New IO.StreamWriter(fs)
    End Sub
 
    Private ln As Integer
 
    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Timer1.Tick
        ln += 1
        sw.WriteLine("A new line " & ln.ToString())
        sw.Flush()
    End Sub
 
End Class

Public Class Form1
 
    Dim fs As IO.FileStream
    Dim sr As IO.StreamReader
 
    Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        sr.Close()
    End Sub
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        fs = New IO.FileStream("F:Test\share.txt", IO.FileMode.Open, _
        IO.FileAccess.Read, IO.FileShare.Write)
        sr = New IO.StreamReader(fs)
    End Sub
 
    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Timer1.Tick
        rtb.AppendText(sr.ReadToEnd())
        rtb.ScrollToCaret()
    End Sub
 
End Class

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