Introduction

The file system events API provides a way for your application to ask for notification when the contents of a directory hierarchy are modified. For example, your application can use this to quickly detect when the user modifies a file within a project bundle using another application.

It also provides a lightweight way to determine whether the contents of a directory hierarchy have changed since your application last examined them. For example, a backup application can use this to determine what files have changed since a given time stamp or a given event ID.

You should read this document if your application works with a large number of files—particularly if your application works with large hierarchies of files.

Organization of This Document

This document is organized into the following chapters: