Bug 19741 - FileSystemWatcher does not pick up changes in files on OSX
Summary: FileSystemWatcher does not pick up changes in files on OSX
Alias: None
Product: Class Libraries
Classification: Mono
Component: System ()
Version: unspecified
Hardware: PC Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2014-05-13 18:02 UTC by Miguel de Icaza [MSFT]
Modified: 2015-04-16 14:47 UTC (History)
6 users (show)

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

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Description Miguel de Icaza [MSFT] 2014-05-13 18:02:57 UTC
The following test case shows the problem, it does not seem to raise any events for changes in files:

Compile like this:
mcs foo.cs

Run like this:
mkdir mydir
mono foo.exe mydir

Then make changes on another window to the contents of mydir.

Possibly connected to bug 16259.

using System;
using System.IO;
using System.Threading;

namespace OtherStuff
    class MainClass
        public static void Main (string[] args)
            var fswatcher = new FileSystemWatcher(); 
            fswatcher.Path = args [0];
            fswatcher.IncludeSubdirectories = true; 
            fswatcher.Renamed += (object sender, RenamedEventArgs e) => { 
                Console.Error.WriteLine ("Renamed '" + e.OldFullPath + "' to '" + e.FullPath + "'"); 
                Console.Error.Flush (); 
            fswatcher.Deleted += (object sender, FileSystemEventArgs e) => { 
                Console.Error.WriteLine("Deleted '"+e.FullPath+"'"); 
                Console.Error.Flush (); 
            fswatcher.Changed += (object sender, FileSystemEventArgs e) => { 
                Console.Error.WriteLine("Changed '"+e.FullPath+"'"); 
                Console.Error.Flush (); 
            fswatcher.Created += (object sender, FileSystemEventArgs e) => { 
                Console.Error.WriteLine("Created '"+e.FullPath+"'"); 
                Console.Error.Flush (); 
            fswatcher.Error += (object sender, ErrorEventArgs e) => { 
                Console.Error.WriteLine ("Error"); 
                Console.Error.Flush (); 
                throw new Exception ("Error"); 

            fswatcher.EnableRaisingEvents = true; 

            Thread.Sleep (int.MaxValue); 
Comment 1 David Fowler 2014-06-24 00:04:27 UTC
Any progress on this?
Comment 2 Miguel de Icaza [MSFT] 2014-06-24 08:47:08 UTC
I'll exchange information for some merging of our pull request :-)
Comment 3 Dylan Borg 2014-07-09 12:55:00 UTC
This bug also occurs on Linux making ASP.NET vNext not respond to file changes
Comment 4 Miguel de Icaza [MSFT] 2014-07-09 14:29:18 UTC
We have a pending pull request, but it only addresses the OSX backend and the test suite is not working, so we need to either determine if this is a regression, or if it is a bug in the implementation).

Linux probably suffers from something similar.  You might want to study the pull request and figure out if Linux suffers from it.

Currently on vacation, so I wont be able to spend much time following up on this.
Comment 5 Rogier Rietdijk 2015-02-05 07:13:07 UTC
It's  still not working...:-(
Comment 6 Miguel de Icaza [MSFT] 2015-04-16 14:47:48 UTC
This is fixed in Mono 4.0