Detection of trash in trash folder

[Scott Baker <smbaker gmail com>]

I have a file system that I'm developer for that is experiencing some
issues with the .Trash folder. Namely, when trash is deleted (for
example by dragging a file from nautilus to the trash bin), the trash
bin icon and the trash bin folder are not updated and the file does
not appear. Looking at the directory on disk, the trash is definitely
in there (nautilus puts it in ~/.Trash-root/ at the mountpoint of the
file system) -- it's just that nautilus seems unaware of the new trash
folder.

I've tried browsing the nautilus source code, but I am unable to
figure out how this monitoring works. Can someone point me to the code
that is responsbile for recognizing when new trash folders are created
and/or when trash folders are modified? In particular, what mechanism
does nautilus use to monitor changes in folders? is it using something
like inotify/dnotify or is it polling to check for changes, or using
some other service?

Thanks,
Scott