Reading Registry in VB6

I commonly recreate ODBC DSN every time I start an application.

It is so quick to recreate that I don't loose time checking for existence!

To recreate it, I use the RegisterDatabase method (of DAO) or rdoRegisterDatabase (of RDO).

emoreau, maybe I'm not clear.  I want to check to see if a particular OBDC DSN entry has been created from inside my VB program.  If it has not, then i must tell the user to quit my VB program and go create it and then start the VB program up again.  

Why ask your user to create a DSN when your application can create one (with RegisterDatabase)?

emoreau, I have no idea. Seems stupid to me too. But don't you think I need to check to see if it exists before I write over it with RegisterDatabase?

As I already said, it is so fast registering it (less than a second) that I don't check if it already exist even if I will overwrite it with the same value.

By overwriting it, I am sure that my DSN is always as I want it to be!

emoreau, I really need to check it before writing it with RegisterDatabase.  I do not trust my users to name it the same thing everytime and other programs depend on this particular OBDC DSN.  Do you know of anyway to check it first? Thank you.

manojamin, that is more of what I was looking for, however, i can not get it to give me the correct answer. In Function IsExistKey "R" always has a value of 2 whether the DSN exists or not.  Any clues?  Thank you so much.

after which call?

R = RegOpenKey(hInKey, subkey$, hSubKey)

or

R = RegQueryValueEx(hSubKey, valname$, 0, dwType, ByVal v$, SZ)

manojamin, after
R = RegQueryValueEx(hSubKey, valname$, 0, dwType, ByVal v$, SZ).  It always returns 2 which after formating the message says "Unable to find file specified".

manojamin, please disregard my stupidity. It is after
R = RegOpenKey(hInKey, subkey$, hSubKey) that i get the value of 2.  THanks.

'forget about that, if it does not work, use this

Private Const SQL_FETCH_NEXT As Long = 1
Private Declare Function SQLAllocEnv Lib "odbc32.dll" (phenv&) As Integer
Private Declare Function SQLDataSources Lib "odbc32.dll" (ByVal henv&, ByVal fDirection%, ByVal szDSN$, ByVal cbDSNMax%, pcbDSN%, ByVal szDescription$, ByVal cbDescriptionMax%, pcbDescription%) As Integer
Sub GetDSNsAndDrivers()
    On Error Resume Next
   
    Dim i As Integer
    Dim sDSNItem As String * 1023
    Dim sDRVItem As String * 1023
    Dim sDSN As String
    Dim sDRV As String
    Dim iDSNLen As Integer
    Dim iDRVLen As Integer
    Dim lHenv As Long         'handle to the environment


    'get the DSNs
    If SQLAllocEnv(lHenv) <> -1 Then
        Do Until i <> SQL_SUCCESS
            sDSNItem = Space(1024)
            sDRVItem = Space(1024)
            i = SQLDataSources(lHenv, SQL_FETCH_NEXT, sDSNItem, 1024, iDSNLen, sDRVItem, 1024, iDRVLen)
            sDSN = VBA.Left(sDSNItem, iDSNLen)
            sDRV = VBA.Left(sDRVItem, iDRVLen)
            Debug.Print sDSN
        Loop
    End If
End Sub

'this will print all the system dsn in debug window...

make this as

    Dim sDSNItem As String * 1023
    Dim sDRVItem As String * 1023

not

    Dim sDSNItem As String * 1024
    Dim sDRVItem As String * 1024

does not really make difference though...

Oh dear God! another mistake!!!!
make this as

    Dim sDSNItem As String * 1024
    Dim sDRVItem As String * 1024

not

    Dim sDSNItem As String * 1023
    Dim sDRVItem As String * 1023

does not really make difference though

thank you