TCP explained

[Suzuran]

I didn't understand a few things about TCP...here's the code with questions in the brackets.

Global $MainSocket = -1   
Global $ConnectedSocket = -1      ;(what is with this variable and why is it "-1" like the $MainSocket? )
Local $MaxConnection = 1; Maximum Amount Of Concurrent Connections
Local $MaxLength = 512; Maximum Length Of String
Local $Port = 1000; Port Number
Local $Server = @IPAddress1; Server IpAddress
TCPStartup()
$MainSocket = TCPListen($Server, $Port)
If $MainSocket = -1 Then Exit MsgBox(16, "Error", "Unable to intialize socket.")  ; (Well, $MainSocket is already -1 because we ;just declared it like that...)
While 1
    $Data = TCPRecv($ConnectedSocket, $MaxLength)      ; ( preety confuzed)         
    If $Data = "~bye" Then
        MsgBox(16, "Session Ended", "Connection Terminated.")
        Exit
    ElseIf $Data <> "" Then 
; Unconditional Receive
        MsgBox(0, "Received Packet", $Data)
    EndIf
    If $ConnectedSocket = -1 Then
        $ConnectedSocket = TCPAccept($MainSocket)
        If $ConnectedSocket <> -1 Then
; Someone Connected
            TCPSend($ConnectedSocket, "Connected!")
        EndIf
    EndIf
WEnd
Func OnAutoItExit()
    If $ConnectedSocket <> - 1 Then
        TCPSend($ConnectedSocket, "~bye")
        TCPCloseSocket($ConnectedSocket)
    EndIf
    If $MainSocket <> -1 Then TCPCloseSocket($MainSocket)
    TCPShutdown()
EndFunc;==>OnAutoItExit

The help in AutoIt isn't very good on TCP for begginers like me... Edited April 30, 2007 by Suzuran

[Suzuran]

There is a "TCPAccept Loop" missing to accept connections on the $MainSocket...

I don't think anything's missing...I got that exemple from here:http://www.autoitscript.com/forum/index.ph...c=20589&hl=.

[Suzuran]

Flawed? I can't belive I spent 30 minutes to decipher it...and still confused on how AutoIt works with TCP.

[Suzuran]

Thanks alot, Larry!!! Now it's clear.

[Shevilie]

Suzuran.. if you need more info theres a lovely thread here

[birdofprey]

The foundation you need before using TCP is generally knowing how to script in AutoIt... once you have a good foundation...

TCP is like this... (Single connection for now)

SERVER

- TCPStartup() always... to tell the TCP Gods you are coming...

- TCPListen() on public IP of this PC .. returns a listening socket handle

- BIG FOREVER LOOP

--- little loop around TCPAccept( listening socket here ) until successful ... returns a connected socket handle

------ return success then exitloop

--- little loop TCPRecv( connected socket here )/TCPSend( connected socket here )

------ to get data if the is any incoming... and send data if there is any to send

------ if TCPRecv() or TCPSend() fails (@error) then exitloop (go back) to TCPAccept() and wait for another...

-

CLIENT

- TCPStartup() always... to tell the TCP Gods you are coming...

- TCPConnect() hopefully successful ... returns a connected socket handle

- little loop TCPRecv( connected socket here )/TCPSend( connected socket here )

--- to get data if the is any incoming... and send data if there is any to send

--- if TCPRecv() or TCPSend() fails (@error) then exit or try to connect again (BIG FOREVER LOOP around this)

Lar.

Thank you very much Larry. Finally !