Most efficient way to check if file is in use

What would be the most efficient way to check if a file, or list of files are in use by another process?

Thanks

try to delete it ;)

I think this should fail if the file is already opened by another program:

Code:

---

Option Explicit

Private Sub Form_Load()
    Dim Filename As String
    On Error GoTo ErrorHandler
    Filename = "g:\videot\trailer.avi"
    Open Filename For Binary Lock Read Write As #1

    Close #1
    Exit Sub
ErrorHandler:
    Select Case Err.Number
        Case 70 'access denied
            MsgBox "File is already opened and reserved by another application.", vbInformation, "Error"
        Case Else
            MsgBox Err.Number & ": " & Err.Description, vbInformation, Filename
    End Select
    Close #1
End Sub

---

:)


Edit Tested and works! I opened VirtualDub with the file mentioned, I got error 70 error denied. If I didn't have the file open in VirtualDub, I got no error.