Raising event on reading file?

Question

I have external app reading files, I want to hook that to get event in my app. But I cannot find a sources hooking ReadFile (or something else that can help me achieve that). Any ideas how to do that? It must be done in User-Mode. I was thinking for something similar to Process Monitor. I wonder how it does it..

Answer 1

In .net you can use the FileSystemWatcher. You will need to add a handler for the Changed event which will detect a change in the last access time (amongst other things).

From the MSDN example linked above:

public static void Foo()
{
    // Create a new FileSystemWatcher and set its properties.
    FileSystemWatcher watcher = new FileSystemWatcher();
    watcher.Path = @"Your path";
    /* Watch for changes in LastAccess time */
    watcher.NotifyFilter = NotifyFilters.LastAccess;
    // Only watch text files.
    watcher.Filter = "*.txt";

    // Add event handlers.
    watcher.Changed += new FileSystemEventHandler(OnChanged);

    // Begin watching.
    watcher.EnableRaisingEvents = true;
}

private static void OnChanged(object source, FileSystemEventArgs e)
{
    // Specify what is done when a file is changed, created, or deleted.
   Console.WriteLine("File: " +  e.FullPath + " " + e.ChangeType);
}