Find oldest file and delete

I am looking to improve an application that writes log files to a particular location. I have a method that looks for the files in a folder and then uses several loops to find the oldest file and delete it.

This is an old method I wrote years ago and I am looking at improving how I find the oldest and then delete it to reduce the time this takes. I could have thousand or so files of at least 2Mb to 12 Mb in size.

Any suggestions on how to proceed and improve?


dim oldest as FolderItem = nil
for each f as FolderItem in myFolder.Children
    if not f.IsFolder and f.Name.EndsWith(".log") then
        if oldest = nil or f.ModificationDate < oldest.ModificationDate then oldest = f
    end if

if oldest <> nil then oldest.Delete


1 Like

On windows you might kill off files older than days with a single shell command
I found this:

ForFiles /p “C:\My Folder” /s /d -30 /c “cmd /c del @file

Substitute the folder path and the amount of days with desired values and you are done.

What platform(s)?

Thanks to everyone who provided suggestions

Platform is OSX using Big Sur XOJO 2021 r1. I have been updating to get daemons to run on the new XOJO RAD looking to reduce CPU % and memory. Originally I had a memory leak because I used the old way of calling using MyApplication with no Super having Initialize, Idle, Final for Methods. I finally fixed that and started looking at other improvements.

@Paul_Rodman After your post I took a look at my previous method that did this work. I have another area that was similar. So I made a few modifications and used that routine there as well. This works on several terminal apps that act as a daemon all working together using inter processor communications.

That suggestion really helped and I have implemented in all solutions.

Here is a bit of what I used in a final version.

If Current_Log_file.Count >= 500 Then
  Var oldest As FolderItem = Nil
  For Each f in Current_Log_file.Children
    If not f.IsFolder and f.Name.EndsWith(".log", ComparisonOptions.CaseSensitive, Locale.Current) Then
      If oldest = nil or f.ModificationDate < oldest.ModificationDate Then oldest = f
    End If
  Var this_file_was_deleted As String = oldest.Name
    If oldest <> Nil Then oldest.Delete
     // Post File was deleted to Running_Log
    Catch e As IOException
     // Post error to Error_Log

End If

Nice code, but you’re accessing oldest.ModificationDate whenever you come across another log file; what if “oldest” disappears or otherwise gets modified while your loop executes?
I’d suggest you use a variable to hold the date.