Monitoring Directories

An application can monitor the contents of a directory and its subdirectories by using the FindFirstChangeNotification, FindNextChangeNotification, and FindCloseChangeNotification functions. Waiting for a change notification is similar to having a read operation pending against a directory and, if necessary, its subdirectories. When something changes within the directory being watched, the read operation is completed. For example, an application can use these functions to update a directory listing whenever a file name within the monitored directory changes.

An application can specify a set of conditions that trigger a change notification by using the FindFirstChangeNotification function. The conditions include changes to file names, directory names, attributes, file size, time of last write, and security. This function also returns a handle that can be waited on by using the wait functions. If the wait condition is satisfied, FindNextChangeNotification can be used to provide a notification handle to wait on subsequent changes.

The FindCloseChangeNotification function closes the notification handle.

Another way to monitor directory changes is by using the ReadDirectoryChangesW function.