I am wondering if there is a way to determine if a file is currently open and currently being written on?

Right now, the program I created is writting information on a user's file in the network.

Every user would have like 2 or 3 instances of the same program running which writes into the said user text file on certain set timer control interval.

Now there is no problem when this 2 or 3 instances are retained however with new workloads sometimes as much as 18 instances of the the said program has to be kept running simultaneously leading to a permission denied error when one instance of the program is writting on the said user file and another instance of the same program tries to write on the same user file as well.

I am thinking to myself if only there is a way for me to figure out if the file is currently being written on, then I can revise the program accordingly to avoid collisions which lead to the permission denied error I mentioned above..

All suggestions welcome and thank you so much for all the kind help you can give.

Gratefully,
Matt

Hello. Regardless of the file type (some types, like .mdb, create a temporary file which you can search for), if you attempt to use a Name instruction on a file to rename it, you get a 75 error if the file is in use, no matter by what process.
So you can easily build a function to do the test, trying to rename the file: if you succeed, the file is not open.
Some kind of stuff like following:

Public Function FileInUse(FilePath As String) As Boolean On Error GoTo ErrHandler     Dim NewName As String     ' assumes that the path actually points to an existant file     NewName = FilePath & "***"     ' try to rename the file     Name FilePath As NewName     ' if the code reaches this point, the file is not in use     ' so we have to restore the previous name before exit     Name NewName As FilePath ExitPoint:     Exit Function ErrHandler:     If Err.Number = 75         FileInUse = True     End If     Resume ExitPoint End Function

It doesn't manage cases like mistyped filenames or dir names, or else, but you can improve this technique by your own.
It's a trick: I found it by myself, and I use it when I need. But it's not documented, and the Name function is not easy to reach in the Help (if you type Name and press F1, you get addressed to the Name property)

Hope it helps.


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