The exclusive property on the FileSystemFlags dictionary is used in tandem with the create property to determine whether or not it's acceptable to require that the file not already exist when the reference to it is created by calling FileSystemDirectoryEntry.getFile() or FileSystemDirectoryEntry.getDirectory().
The create property on the FileSystemFlags dictionary is used to indicate whether or not the file should be created if it's missing. FileSystemFlags is only used when calling FileSystemDirectoryEntry.getFile() or FileSystemDirectoryEntry.getDirectory().