Open Radar

 
Summary: The Backup Core API (CSBackupSetItemExcluded() and CSBackupIsItemExcluded()) do not provide access to Time Machine path-based exclusion done via the Time Machine System Preferences pane. The System Preferences do not show files excluded using Backup Core. Additionally, there is no API to retrieve a list of all fixed-path exclusions.

Steps to Reproduce:

1. Exclude a file at path PATH_A via Time Machine options in System Preferences.

2. Query the state of PATH_A via Backup Core's CSBackupIsItemExcluded().

3. Exlude a file at path PATH_B via CSBackupSetItemExcluded() with excludeByPath == true.

4. Exlude a file at path PATH_B via CSBackupSetItemExcluded() with excludeByPath == false.

5. Look up if PATH_B is excluded in Time Machine options in System Preferences.

Expected Results: In step 2 CSBackupIsItemExcluded() should return YES and set *excludeByPath = YES as the exclusions done via System Preferences seem to be fixed-path. In step 5, PATH_B should appear among excluded files in System Preferences.

Actual Results: Exclusions via Backup Core do not affect exclusions via System Preferences and vice versa. Using either interface one cannot say certainly which files are really excluded. 

Regression: None.

Notes: What I have said about Backup Core applies to the tmutil command as well. Even if there is a reason to keep two separete databases of fixed-path exclusions, it would be more transparent to:

1. provide at least read-only access via an extension to the Backup Core API to the preference pane exclusions.

-- and perhaps also:

2. provide read-only access to programmatic (Backup Core) exclusions via Time Machine preferences and Finder info windows.

It would also be helpful to be able to retrieve a list of all fixed-path exclusions programmatically.