Device Manager won't unmount

[Patrick O'Callaghan]

On Wed, 2010-06-02 at 09:54 +0100, Anne Wilson wrote:
> On Wednesday 02 June 2010 02:00:10 Patrick O'Callaghan wrote:
> 
> > Very recently I've found that when I try to unmount a removable
> device
> 
> > using the Device Manager plasmoid, it tells me the device is busy
> even
> 
> > when it isn't (as verified using fuser). I can unmount it from a
> Shell
> 
> > with no problems.
> 
> > 
> 
> > This used to work in F12. I updated to F13 last week and it still
> 
> > worked. I've done several updates since then and it was working till
> 
> > yesterday. No updates since yesterday have anything to do with KDE.
> 
> > 
> 
> > Ideas?
> 
> > 
> 
> No ideas, other than to say that I have kde 4.4.80-2, updated to
> yesterday around noon, and used the device notifier satisfactorily in
> the afternoon.

I've (partly) figured it out. The fault appears to be in an interaction
with Nautilus. Nautilus is running because I use a Dropbox applet, which
has a nautilus front-end. I've actually had this for some time, but the
nautilus process wasn't active because I hadn't used Dropbox for a
while. I conjecture that using it activated nautilus, which then takes
possession of newly-inserted devices. This is born out by two additional
data points:

1) When I unmount the device and then remount it from dev-man, without
physically removing it, I can use dev-man to safely remove it again with
no error message.

2) Killing the nautilus process makes dev-man work correctly.

Now I have to figure out how to configure nautilus to behave properly.
The weird thing is that fuser definitely shows no processes using the
device, or having their current directory on it. That part I don't get.

poc