Can g_file_monitor_file () report events from before it was created?

[Peter Clifton <pcjc2 cam ac uk>]

Hi,

I'm working on some code to monitor for file changes in our application,
and ran into a bit of a problem today with the Save-As case.

The order of operations is something like:

1. File monitor exists on the document file which was loaded last
2. User hits File->Save as.. (and enters a filename)
3. Core of app saves file into the new file name
4. File monitor does not fire, as the saved file is not the one being monitored
5. Core of app notifies the GUI (with the file monitor) that the document we should be watching is now in the 
new filename.
6. g_object_unref() the old file monitor
7. Create new file monitor on the new file.

After this happens, I actually get a change event fire from the new file
monitor - despite the changes having been saved by the app's core
(fopen / fclose directly to the file in question), before I even created
the file monitor.

Is it possible that Glib / GIO is caching some state incorrectly, and
spotting on-disk changes from _before_ I created the file monitor, or is
it more likely that the file doesn't "hit the disk" until some time
after I fclose() it - and that it spots the change at this point in
time?

Any ideas what I might be doing wrong here?

(PS. I got the feeling GLib / GIO is using polling, not anything clever
like inotify to spot changes - is this correct?)

Best regards,

-- 
Peter Clifton

Electrical Engineering Division,
Engineering Department,
University of Cambridge,
9, JJ Thomson Avenue,
Cambridge
CB3 0FA

Tel: +44 (0)7729 980173 - (No signal in the lab!)
Tel: +44 (0)1223 748328 - (Shared lab phone, ask for me)