A command line tool that uses dispatch sources to monitor file system events

Example of monitoring a create and delete:

% watch ~/Desktop 
Watching: /Users/user/Desktop
[2010-11-07 23:31:13 -0800] Added: /Users/user/Desktop/file
[2010-11-07 23:31:13 -0800] Changed: /Users/user/Desktop
[2010-11-07 23:31:16 -0800] Removed: /Users/user/Desktop/file
[2010-11-07 23:31:16 -0800] Changed: /Users/user/Desktop
[2010-11-07 23:31:16 -0800] Changed: /Users/user/Desktop/.DS_Store
[2010-11-07 23:31:16 -0800] Changed: /Users/user/Desktop/.DS_Store
[2010-11-07 23:31:21 -0800] Changed: /Users/user/Desktop/.DS_Store
[2010-11-07 23:31:21 -0800] Changed: /Users/user/Desktop/.DS_Store
                                    

Example of creating a adding several directories and removing with a maximum watch depth of 10:

% watch -r 10  
Watching: /Users/user/src/a
[2010-11-07 23:35:02 -0800] Added: /Users/user/src/a/s
[2010-11-07 23:35:02 -0800] Changed: /Users/user/src/a
[2010-11-07 23:35:10 -0800] Removed: /Users/user/src/a/s/d/f/g/2/r
[2010-11-07 23:35:10 -0800] Removed: /Users/user/src/a/s/d/f/g/2
[2010-11-07 23:35:10 -0800] Removed: /Users/user/src/a/s/d/f/g
[2010-11-07 23:35:10 -0800] Removed: /Users/user/src/a/s/d/f
[2010-11-07 23:35:10 -0800] Removed: /Users/user/src/a/s/d
[2010-11-07 23:35:10 -0800] Removed: /Users/user/src/a/s
[2010-11-07 23:35:10 -0800] Removed: /Users/user/src/a/s
[2010-11-07 23:35:10 -0800] Changed: /Users/user/src/a