[tlug] Permissions are like Rubik's cubes

[Dave M G <martin@example.com>]

TLUG,

I've got this USB thumb drive, where I keep a directory that has a bunch 
of text documents in it. Just plain text, nothing else to them.

I keep them on my thumb drive so that I can access them both from my 
laptop and my desktop. I tend to work on them mostly on the laptop and 
back them up to my desktop, but in any case, it's possible that any one 
file could have been created from either computer.

When I double click on any of them, I get a dialogue that asks if I want 
to display them or view them. That's an extra step I don't need, so I 
just need to change their permissions settings so that they're not 
executable.

Not so easy, though. For some reason, I can edit and delete them, but I 
can't change their permissions or ownership. Each of them says the owner 
and group is "root", but even if I go into "sudo" mode, I can't change 
the permissions on any of them. Every time I try to switch off the 
"executable" setting in the Gnome GUI, it just reverts back to what it 
was before. From the command line, whatever I try to change, it tells me 
"permission denied".

I've tried to change the settings on these files from both computers, 
thinking that maybe the permissions are bound one of the machines. But 
no, I can't change the permissions from anywhere.

Weird. Or at least I think so. How can you have a file that you have the 
ability to delete or rewrite, but can't change its permissions settings, 
or who owns it? Surely if I can delete it, then it's a copy that I 
should be able to do pretty much anything else to ...?

How do I get control of these files?

Any advice much appreciated.

--
Dave M G
http://www.tlug.jp/wiki/User:Dave_M_G