paolo070697
asked on
Checking CD on serial port with API
Hello, I need a piece of _working_ VB4 (32 bit) code (related declarations included) to check if there's CD (carrier detect) on COM1, without using MSComm control: I need to check the state without disturbing (or locking) a Remote Access procedure from getting control of the port, and I think I need to use Win32 API.
Ie, I need to _spy_ the connection to check when data exchange begins and ends.
Thank you,
Paolo
Ie, I need to _spy_ the connection to check when data exchange begins and ends.
Thank you,
Paolo
An alternate way is to use the RasEnumConnections to get the names of the currently active connections. This will not detect the actual modem carrier, but it will detect when there is an active connection, which I believe would fill the purpose?
ASKER
Yes, I think it would fill the purpose, but I've checked and I don't happen to have the necessary VB declarations in Win32api.txt (or the like) that comes with VB. I would consider the question answered (and appreciate very much it, by the way), if you put in ALL the necessary declarations (including constants) and also some lines of working code, or someplace where to get them (declarations, constants, type definitions and samples for VB, of course).
Thank you,
Paolo
Thank you,
Paolo
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ASKER
Just one mre, and I'll grade the question: since the RasEnumConnections says ON before the connection is really on, I'd like to use the RasGetConnectStatus, but I can't get it to work, probably because I haven't figured out the right parameters (the main problem is that I don't have the file with declarations nor the C header file), mainly RASCONNSTATE enum and the RASCS_DONE constant. May I impose further on you for the necessary delarations ?
Thank you,
Paolo
Thank you,
Paolo
Sure. If you'd post your e-mail, I'll send you a copy of the full C header files too.
I might as well send you all the VB code I've written as samples for different people. This is really code for connecting and disconnecting, but I use the RasGetConnectStatus function in it too.
You may notice that the structures are bigger than sum of all members described in the API, probably due to alignment.
Private Const RASCS_DONE = &H2000
Private Const RASCS_Connected = RASCS_DONE
Private Const RASCS_Disconnected = RASCS_DONE + 1
Private Type rasconn
dwSize As Long
hrasconn As Long
szEntryName As String * 257
szDeviceType As String * 17
szDeviceName As String * 130
End Type
Private Type RASCONNSTATUS
dwSize As Long
rasconnstate As Long
dwError As Long
szDeviceType As String * 17
szDeviceName As String * 131
End Type
Private Type RASDIALPARAMS
dwSize As Long
szEntryName As String * 257
szPhoneNumber As String * 129
szCallbackNumber As String * 129
szUserName As String * 257
szPassword As String * 257
szDomain As String * 19
End Type
Private Declare Function RasEnumConnections Lib "rasapi32" Alias "RasEnumConnectionsA" (buf As rasconn, numbytes As Long, numconns As Long) As Long
Private Declare Function RasDial Lib "rasapi32" Alias "RasDialA" (ByVal extensions As Long, ByVal phonebook As String, params As RASDIALPARAMS, ByVal notifiertype As Long, ByVal notifier As Long, rasconn As Long) As Long
Private Declare Function RasHangUp Lib "rasapi32" Alias "RasHangUpA" (ByVal rasconn As Long) As Long
Private Declare Function RasGetConnectStatus Lib "rasapi32" Alias "RasGetConnectStatusA" (ByVal rasconn As Long, connstatus As RASCONNSTATUS) As Long
Dim rasconn As Long
Private Sub Command1_Click()
Dim numbytes As Long, numconns As Long, success As Long
Dim rc As rasconn
rc.dwSize = Len(rc)
numbytes = Len(rc)
success = RasEnumConnections(rc, numbytes, numconns)
If numbytes > 0 Then
' Connect
Print "Hanging up "; rc.szEntryName
RasHangUp rc.hrasconn
Else
'
Print "not connected"
End If
End Sub
Private Sub Command2_Click()
Dim status As Long
Dim rdp As RASDIALPARAMS
Dim rcs As RASCONNSTATUS
Dim rasconn As Long
rdp.dwSize = Len(rdp)
rdp.szEntryName = "Swipnet" & Chr(0) ' select ras entry to use
rdp.szPhoneNumber = Chr(0) ' use phone number from ras entry
rdp.szCallbackNumber = Chr(0) ' use callback number from ras entry
rdp.szUserName = "UserName" & Chr(0) ' user name for PPP logon
rdp.szPassword = "Password" & Chr(0) ' password for PPP logon
rdp.szDomain = "*" & Chr(0) ' use default domain
status = RasDial(0, vbNullString, rdp, 0, 0, rasconn)
If status = 0 Then
rcs.dwSize = Len(rcs)
status = RasGetConnectStatus(rascon
If status <> 0 Then
Debug.Print "RasGetConnectStatus error " & status
RasHangUp rasconn
Exit Sub
Else
If rcs.dwError Then
Debug.Print "Connection failed, error " & rcs.dwError
RasHangUp rasconn
Exit Sub
End If
If rcs.rasconnstate = RASCS_Connected Then
Debug.Print "Connected"
Else
RasHangUp rasconn
End If
End If
Else
Debug.Print "RasDial error " & status
If rasconn Then RasHangUp rasconn
End If
End Sub
Private Sub Command3_Click()
RasHangUp rasconn
End Sub
I might as well send you all the VB code I've written as samples for different people. This is really code for connecting and disconnecting, but I use the RasGetConnectStatus function in it too.
You may notice that the structures are bigger than sum of all members described in the API, probably due to alignment.
Private Const RASCS_DONE = &H2000
Private Const RASCS_Connected = RASCS_DONE
Private Const RASCS_Disconnected = RASCS_DONE + 1
Private Type rasconn
dwSize As Long
hrasconn As Long
szEntryName As String * 257
szDeviceType As String * 17
szDeviceName As String * 130
End Type
Private Type RASCONNSTATUS
dwSize As Long
rasconnstate As Long
dwError As Long
szDeviceType As String * 17
szDeviceName As String * 131
End Type
Private Type RASDIALPARAMS
dwSize As Long
szEntryName As String * 257
szPhoneNumber As String * 129
szCallbackNumber As String * 129
szUserName As String * 257
szPassword As String * 257
szDomain As String * 19
End Type
Private Declare Function RasEnumConnections Lib "rasapi32" Alias "RasEnumConnectionsA" (buf As rasconn, numbytes As Long, numconns As Long) As Long
Private Declare Function RasDial Lib "rasapi32" Alias "RasDialA" (ByVal extensions As Long, ByVal phonebook As String, params As RASDIALPARAMS, ByVal notifiertype As Long, ByVal notifier As Long, rasconn As Long) As Long
Private Declare Function RasHangUp Lib "rasapi32" Alias "RasHangUpA" (ByVal rasconn As Long) As Long
Private Declare Function RasGetConnectStatus Lib "rasapi32" Alias "RasGetConnectStatusA" (ByVal rasconn As Long, connstatus As RASCONNSTATUS) As Long
Dim rasconn As Long
Private Sub Command1_Click()
Dim numbytes As Long, numconns As Long, success As Long
Dim rc As rasconn
rc.dwSize = Len(rc)
numbytes = Len(rc)
success = RasEnumConnections(rc, numbytes, numconns)
If numbytes > 0 Then
' Connect
Print "Hanging up "; rc.szEntryName
RasHangUp rc.hrasconn
Else
'
Print "not connected"
End If
End Sub
Private Sub Command2_Click()
Dim status As Long
Dim rdp As RASDIALPARAMS
Dim rcs As RASCONNSTATUS
Dim rasconn As Long
rdp.dwSize = Len(rdp)
rdp.szEntryName = "Swipnet" & Chr(0) ' select ras entry to use
rdp.szPhoneNumber = Chr(0) ' use phone number from ras entry
rdp.szCallbackNumber = Chr(0) ' use callback number from ras entry
rdp.szUserName = "UserName" & Chr(0) ' user name for PPP logon
rdp.szPassword = "Password" & Chr(0) ' password for PPP logon
rdp.szDomain = "*" & Chr(0) ' use default domain
status = RasDial(0, vbNullString, rdp, 0, 0, rasconn)
If status = 0 Then
rcs.dwSize = Len(rcs)
status = RasGetConnectStatus(rascon
If status <> 0 Then
Debug.Print "RasGetConnectStatus error " & status
RasHangUp rasconn
Exit Sub
Else
If rcs.dwError Then
Debug.Print "Connection failed, error " & rcs.dwError
RasHangUp rasconn
Exit Sub
End If
If rcs.rasconnstate = RASCS_Connected Then
Debug.Print "Connected"
Else
RasHangUp rasconn
End If
End If
Else
Debug.Print "RasDial error " & status
If rasconn Then RasHangUp rasconn
End If
End Sub
Private Sub Command3_Click()
RasHangUp rasconn
End Sub
ASKER
Sure, thanks ! You can send them at asioli@geocities.com.
Thank you very much,
Paolo
Thank you very much,
Paolo