stdin is corrupt when reading it from non UI thread

Question

I am trying to receive messages from Chrome using Google NativeMessaging, my WinForms application reads the messages sent from my extension in Chrome by calling the following function each 0.1s:

Public Function read_message() As String
        'Read in first 4 bytes for length...
        Dim stdin As Stream = Console.OpenStandardInput()

        Dim bytelen(LENGTH_BYTE_COUNT - 1) As Byte
        stdin.Read(bytelen, 0, LENGTH_BYTE_COUNT)

        Dim msglen As Integer = BitConverter.ToInt32(bytelen, 0)

        'Read the message
        Dim msg As String = ""
        For i As Integer = 0 To msglen - 1
            msg &= ChrW(stdin.ReadByte())
        Next i

        stdin.Close()
        stdin.Dispose()

        Return msg
    End Function

Everything works perfectly in the scenario I explained above, however, I wanted this function to run repeatedly in a different Thread.

So when I am creating new thread, that has similar timer with similar interval, the results become a mess, text messages from Chrome overlaps, some messages are simply missed, and some times return corrupt messages, and I can't understand why this works perfectly in UI thread, while gives strange results in a different one, even if I relax reading time interval, any clues?

P.S

As a side question, I am actually not sure that using a timer to read messages from stdin is best approach given that I have to use Winforms, is there any better way to detect when a message "arrives" into stdin stream?

Answer 1

Found the soltution here: Very Slow to pass “large” amount of data from Chrome Extension to Host (written in C#)

The problem was that stdin.ReadByte is very slow operation, and should be replaced with StreamReader(stdin).