Scan for changed files

I'm looking for a good efficient method for scanning a directory structure for changed files in Windows XP+. Something like how git does it is exactly what I'm looking for, when running a git status it displays all modified files, all new (untracked) files and deleted files very quickly which is exactly what I would like to do.

I have a basic model up and running which performs an initial scan and stores all filenames, size, dates and attributes.

On a subsequent scan it checks if the size, attributes or date have changed and marks as a changed file.

My issue now comes in detecting moved and deleted files. Is there a tried and tested method for this sort of thing? I'm struggling to come up with a good method.

I should mention that it will eventually use ReadDirectoryChangesW to monitor files and alert the user when something changes so a full scan is really a last resort after the in开发者_如何学运维itial scan.

Thanks, J

EDIT: I think I may have described the problem badly. The issue I'm facing is not so much detecting the changes - I have ReadDirectoryChangesW() using IOCP on multiple threads to detected when a change happens, the issue is more what to do with the information. For example, a moved file is reported as a delete followed by a create and a rename comes in 2 parts, old name, followed by new name. So what I'm asking is how to differentiate between the delete as part of a move and an actual delete. I'm guessing buffering the changes and processing batches would be an option but feels messy.

In native code FileSystemWatcher is replaced by ReadDirectoryChangesW. Using this properly is not simple, there is a good baseline to build off here.

I have used this code in a previous job and it worked pretty well. The Win32 API itself (and FileSystemWatcher) are prone to problems that are described in the docs and also discussed in various places online, but impact of those will depending on your use cases.

EDIT: the exact change is indicated in the FILE_NOTIFY_INFORMATION structure that you get back - adds, removals, rename data including old and new name.

I voted Liviu M. up. However, another option if you don't want to use the .NET framework for some reason, would be to use the basic Win32 API call FindFirstChangeNotification.

You can use USN journaling if you are up to it, that is pretty low level (NTFS level) stuff.

Here you can find detailed information and source code included. It is written in C# but most of it is PInvoking C/C++ functions.