TCP hanging problem...

[mark smit]

Hello...

Could maybe a couple of you try this example code out and let me know what happens on your machine. I cant get this code to run without hanging.

#compile exe
#register none
#include "win32api.inc"
#include "wsock32.inc"

function pbmain() as long
  dim message as string
  dim buffer as string
  dim hsock as long


rem Open socket to PowerBasic FTP
  hsock = freefile
  tcp open port 21 at "ftp.powerbasic.com" as hsock timeout 500

  if err then
    msgbox "Unable to connect to FTP.POWERBASIC.COM"
    exit function
  else
    msgbox "We connected ok..." & $CRLF & _
           "but now let's see if we can get" & $CRLF & _
           "a response from the server."
  end if


rem Read welcome message
  message = ""

  do
    tcp line hsock, buffer    rem program hangs up here in debugger
    message = (message & $CRLF & buffer)
  loop while len(buffer)

  msgbox message


rem Send username and retreive message
  tcp print hsock, "user anonymous"

  message = ""
  do
    tcp line hsock, buffer
    message = (message & $CRLF & buffer)
  loop while len(buffer)

  msgbox message

rem Send password and retreive message
  tcp print hsock, "pass [email protected]"

  message = ""
  do
    tcp line hsock, buffer
    message = (message & $CRLF & buffer)
  loop while len(buffer)

  msgbox message & format$(len(buffer))

rem Close socket and bail out
  tcp close hsock
end function

Cheers!

[Lance Edmonds]

The code is running, but it is waiting for a second "line" of text which will never be received as the code is written... try this slight variation (you'll still need to add additional error testing, but this modification works fine for me):

#COMPILE EXE
#REGISTER NONE
#INCLUDE "win32api.inc"
#INCLUDE "wsock32.inc"

FUNCTION PBMAIN() AS LONG
  DIM message AS STRING
  DIM hsock AS LONG

REM Open socket to PowerBasic FTP
  hsock = FREEFILE
  TCP OPEN PORT 21 AT "ftp.powerbasic.com" AS hsock TIMEOUT 5000
  IF ERR THEN
    MSGBOX "Unable to connect to FTP.POWERBASIC.COM"
    EXIT FUNCTION
  ELSE
    MSGBOX "We connected ok..." & $CRLF & _
           "but now let's see if we can get" & $CRLF & _
           "a response from the server."
  END IF
 
REM Read welcome message
  TCP LINE hsock, Message    
  MSGBOX message
 
REM Send username and retreive message
  TCP PRINT hsock, "user anonymous"
  TCP LINE hsock, Message
  MSGBOX message
 
REM Send password and retreive message
  TCP PRINT hsock, "pass [email protected]"
  TCP LINE hsock, Message
  MSGBOX message
 
REM Close socket and bail out
  TCP CLOSE hsock
  MSGBOX "Finished!"
END FUNCTION

------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[mark smit]

Hello Lance!

I understand exactly what you mean here but this only works if the FTP server returns one line messages. The PowerBasic FTP server as well as many others return more than one line. I have also found a wierd quirk, Some FTP servers send an EOF after the first line has been written, even though there are a couple more lines to read in after that...

The Welcome message seems to be the real problem area for this.

Cheers!

------------------

[Semen Matusovski]

Mark --
try this

   #Compile Exe
   #Register None
   #Dim All
   #Include "win32api.inc"
   #Include "wsock32.inc"

   Global hsock As Long
   
   Global MessageF As String
   Sub DMessage (SendMsg As String)
      Dim Message As String
      MessageF = ""
      If SendMsg <> "" Then Tcp Print hsock, SendMsg Else SendMsg = "Welcome"
      Do
         Tcp Line hsock, Message
         MessageF = MessageF + Message + $CRLF
      Loop Until Mid$(Message, 4, 1) = " "  Or Len(Message) = 3
      MsgBox MessageF, , SendMsg
   End Sub

   Function PbMain() As Long
      hsock = FreeFile
      Tcp Open Port 21 At "ftp.powerbasic.com" As hsock TIMEOUT 5000
      If Err Then
         MsgBox "Unable to connect"
         Exit Function
      End If
      DMessage ""
      Do
         Select Case Val(Mid$(MessageF, 1, 3))
            Case 220 ' User
               DMessage "user anonymous"
            Case 331 ' password
               DMessage "pass [email protected]"
            Case 230 ' logged in, now possible to continue
               MsgBox "Finished": Exit Do
            Case Else
               MsgBox "Unexpected reply": Exit Do
         End Select
      Loop
      Tcp Close hsock
   End Function

But should say, that RFC for FTP is enough difficult.
If you seriously want to work with FTP, you should search Don Dickinson's PB library (www.basicguru.com) - at least, I saw it some monthes ago, or to use commercial Marshall Software DLL (search by Marshall and you will find http).

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