Now, before you finish thinking "Dear God! why would you want to allow that?!?", I'm wondering if it's possible.

What I'm trying to solve, could be solved in other ways, but this puts it in the functional realm of other, non *nix-y admins at my work place.

What I want to achieve is: Have a shortcut / file / what-have-you be able to be double clicked (to run it), over a samba connection, and have umount /path/to/ext-drive executed.

This could fall on it's face in many areas, one of course being the aforementioned "Why?!!?!", and I've just remembered that the mount is done via root's cron, so it may not even be able to be unmounted via some other named smb user.

Practically, I'm thinking of linking to a .sh file outside of the shares in an attempt to isolate anything with execute away from samba user tinkering.

Any thoughts?

edit

I should add that the USB ext. drive is mounted via the script that does the backups. It's not mounted at drive connection. This was hopefully a way to get around the randomly occurring failures to unmount that have cropped up in the last few weeks.

I had also thought that I could put something in cron to check if the backup process has stopped executing, if the drive is still connected, and if so - unmount it.

another edit

I'm starting to realise the futility of this question. As I said in the comments below the OP here, double clicking a file on the share from my computer, won't execute something on the server.