I have a very simple little program that connects to  our email server to
send out emails.  When I compiled it with .VS2003 (net 1.1), it works fine.
with VS2005 (.net 2.0), it hangs on the last ReadInfo

Any suggestions?  thanks!

  Public Function send2() As String
        Dim err As String = ""

        soc = ConnectSocket(Server, 25)
        Debug.Write(ReadInfo(err) & vbCrLf)
        WriteInfo("HELO", Err)
        Debug.Write(ReadInfo(err) & vbCrLf)

        WriteInfo("MAIL FROM:" & From, err)
        Debug.Write(ReadInfo(err) & vbCrLf)

        WriteInfo("RCPT TO:" & "RTorcell***@mydomain.com", err)
        Debug.Write(ReadInfo(err) & vbCrLf)

        WriteInfo("DATA", err)
        Debug.Write(ReadInfo(err) & vbCrLf)

        WriteInfo("This is a test" & vbCrLf & "." & vbCrLf, err)
        Debug.Write(ReadInfo(err) & vbCrLf)

        WriteInfo("QUIT", err)
        Debug.Write(ReadInfo(err) & vbCrLf)  'CODE HANGS HERE- SEE BELOW
        soc.Close()
    End Function

    Private Function WriteInfo(ByVal Info As String, ByRef err As String) As
String
        Dim bytes As Byte()
        Dim ASCII As Encoding = Encoding.ASCII
        bytes = ASCII.GetBytes(Info & vbCrLf)
        soc.Send(bytes, bytes.Length, 0)
    End Function

    Private Function ReadInfo(ByRef Err As String) As String
        Try
            Dim bytes As Int32
            Dim RecvBytes(256) As Byte
            Dim ASCII As Encoding = Encoding.ASCII
            bytes = soc.Receive(RecvBytes, RecvBytes.Length, 0)  'HANGS HERE
ON LAST ReadInfo
            Return ASCII.GetString(RecvBytes, 0, bytes)
        Catch ex As Exception
            Err = ex.Message
        End Try
    End Function

On Thu, 22 Mar 2007 09:15:10 -0700, Rob T 
<RTorcellini@DONTwalchemSPAM.com> wrote:

Your code displays the classic beginner bug of assuming that a single 
receive will actually receive every byte that was sent.  That's not true.  
The Receive method can return anywhere between 1 and the total numebr of 
bytes sent.  It is your responsibility to keep receiving bytes until 
you've gotten as many as you expect or need.

I would be surprised if changing the compiler is actually what changed the 
behavior...but regardless, I suspect that if you fix the code so that in 
ReadInfo, you loop until you've read as many bytes as you really want, it 
will work fine.  In the specific example, it appears that you want to 
receive until you've gotten the cr/lf terminator for each line of data.  
For different situations, you will use different criteria.

Pete

As a followup to this.  There is nothing wrong with the code.  Our IT dept
had deployed a new version of Symantec Antivirus and it had the SMTP client
installed....blocks just about everything!  Once I disabled it....let the
good times roll!


Show quoteHide quote

On Fri, 23 Mar 2007 07:26:19 -0700, Rob T 
<RTorcellini@DONTwalchemSPAM.com> wrote:

Well, your code still has the bug I describe.  So it's not actually true 
that "there is nothing wrong with the code".  It may work fine now, but it 
is likely to break some time in the future.

Convert.ToInt32("0") throws an exception, some systems
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