Is there a way that users get a notification when a file is uploaded through ftp to a specific folder?
It is not technically possible.
maybe with a cron to scan folders?
There is no way to tell which files are new, meaningful or how they are were created. Apps can create temporary files, you wouldn't want to be notified about any file.
If one took the manual task of uploading files via FTP, then the person can send the notification as well. If the file was uploaded/created programatically, then the same program could be set to send the notifications itself.
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