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[PhilOfWalton]

In a multi-user environment with one BE database and several FE databases, is it possible without using additional tables to find out which other FE computers are linked to the BE.

I want to ensure exclusive use before compacting or copying the BE

Thanks

Phil

[NeoPa]

The info's in the ACCDB or LDB file Phil.

Full deconstruction of the file can be tricky, but it should have a specific size if you, and only you, have it open.

[zmbd]

Go to the location of the backend file
the "backendname.laccdb" file may have this information...
In my WidowsOS configuration I can right-click the file
In the pop-up I have the {Send To} menu option and have Notepad as one of the options.
Google Search: Add Notepad to SendTo

Sending this file to notepad usually gives me at least a list of PC's connected to the database.

If there isn't a "backendname.laccdb" file then no-one has a lock on the file, that is to say, no one has a table, query, or form bound to a table open and active. This doesn't mean that a frontend isn't open, just that there are no current locks.

Personally, I use a combination of a hidden form and the tables to keep track of the current users, I find this to be much more reliable than just the laccdb file. The hidden form is on a timer event to check for a "maintenance request" record. On startup, this form also tries the connection and is error trapped to look for an exclusive (Access 2013, error 3045) and gracefully exits of true.

(opps, the 3 year old needed my attention and I thought I had posted this earlier... :( )

[PhilOfWalton]

Thanks guys, I had never investigated lAccDb files.

This is what I have come up with, the only hard coding is to use a known linked table ("TblMemberLog")

Option Compare Database
Option Explicit
 
Private Type UserRec
   bMach(1 To 32) As Byte  ' 1st 32 bytes hold machine name
   bUser(1 To 32) As Byte  ' 2nd 32 bytes hold user name
End Type
 
'   Subject : WhosOn()
'   Purpose : Will read *.LAccDb file and read who's currently
'             logged on and their station name.
'
'             The LAccDb file has a 64 byte record.
'
'             The station name starts at byte 1 and is null
'             terminated.
'
'             Log-in names start at the 33rd byte and are
'             also null terminated.
'
'-------------------------------------------------------------------------------------
Function WhosOn() As String
 
    On Error GoTo Err_WhosOn
 
    Dim IntlAccDeFile As Integer, IntStart As Integer
    Dim IntLOF As Integer, i As Integer
    Dim FileName As String
    Dim sLogStr As String, sLogins As String
    Dim ComputerName As String, UserName As String
    Dim rUser As UserRec    ' Defined in General
    Dim MyDb As Database
    Dim DataPath As String
 
    ' Get the name of the Data Path
    Set MyDb = CurrentDb
 
    DataPath = MyDb.TableDefs("TblMemberLog").Connect
    If DataPath = "" Then                                   ' Local table
        DataPath = MyDb.name
    End If
 
    DataPath = Replace(DataPath, ";DATABASE=", "")          ' Get just the name
 
    i = InStrRev(DataPath, ".")
    DataPath = Left(DataPath, i) & "l" & MID(DataPath, i + 1)
    'Debug.Print DataPath
 
    ' Test for valid file, else Error
    FileName = Nz(Dir(DataPath))
    If FileName = "" Then
        MsgBox "Couldn't find the file for the data" & vbCrLf & DataPath
        Exit Function
    End If
 
    IntStart = 1
    IntlAccDeFile = FreeFile
 
    Open DataPath For Binary Access Read Shared As IntlAccDeFile
    IntLOF = LOF(IntlAccDeFile)
    Do While Not EOF(IntlAccDeFile)
        Get IntlAccDeFile, , rUser
        With rUser
            i = 1
            ComputerName = ""
            While .bMach(i) <> 0
                ComputerName = ComputerName & Chr(.bMach(i))
                i = i + 1
            Wend
            i = 1
            UserName = ""
            While .bUser(i) <> 0
                UserName = UserName & Chr(.bUser(i))
                i = i + 1
            Wend
        End With
        sLogStr = ComputerName & " -- " & UserName
        If InStr(sLogins, sLogStr) = 0 Then
            sLogins = sLogins & sLogStr & "~"          ' Separate the computers & Usrs with a tilde
        End If
        IntStart = IntStart + 64                          'increment to next record offset
    Loop
    Close IntlAccDeFile
    WhosOn = sLogins
 
Exit_WhosOn:
    Exit Function
 
Err_WhosOn:
    If Err = 68 Then
        MsgBox "Couldn't populate the list", 48, "No LDB File"
    Else
        MsgBox "Error: " & Err.Number & vbCrLf & Err.Description
        Close IntlAccDeFile
    End If
    Resume Exit_WhosOn
 
End Function
 

Phil