Bug 10120 - When will FileSystemWatcher be implemented on MacOS?
Summary: When will FileSystemWatcher be implemented on MacOS?
Alias: None
Product: Class Libraries
Classification: Mono
Component: System ()
Version: unspecified
Hardware: PC Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2013-02-07 06:16 UTC by ian
Modified: 2013-07-12 05:54 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

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Description ian 2013-02-07 06:16:12 UTC
We're using Mono for cross-platform development and have a critical requirement for a FileSystemWatcher.
I'm alarmed at the current state of FileSystemWatcher. There's little documentation of the issues on a Mac, but it's clear there's a number of issues with the OSX FileSystemWatcher:

- Only CreateFile events are detected. This is completely inadequate 
- Sub-folders aren't reliably  tracker. Again this is can't be considered a FileSystemWatcher implementation and certainly nowhere near the .Net equivalent.
- It uses kQueue as the backend. This is considered inapproriate. It should use the new fsEvents on Macs.

Moreover, there are a few implemnetations of fsevents FileWatchers on the Mac. We've researched them, but I'm nervous about using them. Could they at least be used as a start for the implementation on Mac (I'm thinking SparkleShare).

This is a big issue for us and greatly hinders out use of Mono on Mac.
Comment 1 ian 2013-02-07 06:20:54 UTC
Note we've tested again 3.0.1 -> 3.0.3. All are affected.
Comment 2 ian 2013-02-19 10:27:26 UTC
We are still waiting for an official implementation. For now we're working with Zip archives from Xaramin against the licensed dll....
Comment 3 ian 2013-03-28 04:36:15 UTC
This has been fixed with the release of the official FSEvents component with Xam.MAc 1.2
Comment 4 wojtuch 2013-07-12 05:54:11 UTC
The issue still exists for subfolders that exist at the time the FSWatcher is created..
Every subfolder of the root folder is ignored, only those which are created when the FSWatcher is working are properly watched