1. Summarise the issue (what were doing, what went wrong?)

Linux:

# cd /
# darcs init
# darcs add -r etc
Ignoring non-repository paths: etc/

darcs failed:  No valid arguments were given


2. What behaviour were you expecting instead?

darcs accepting adding /etc to repo

3. What darcs version are you using? 

darcs compiled on Jan 29 2015, at 09:56:37

Context:

[TAG 2.8.5

Ganesh Sittampalam <ganesh@earth.li>**20140825204639
 Ignore-this: 4e6c90569ceab19a231cdd4c5089b4c2
] 

4. What operating system are you running?
  
linux debian jessie

5. Workaround (ugly): 

# mount --bind / repo
# cd repo
# darcs init  
# darcs add -r etc
# umount repo

Please note that darcs does not track file permissions. This makes a
repo at "/" highly insecure and I strongly recommend not to do that.

Note that the behaviour described by e.ex.exi.exit is the same in Darcs
HEAD (2.13). 

What seems weird is that Darcs enable to initialize a repository, then
does not let  us add files. I believe it would be better to have an
all-or-nothing behaviour.

bf wrote:
> Please note that darcs does not track file permissions. This makes a
> repo at "/" highly insecure and I strongly recommend not to do that.

I believe that darcs could be a good tool to track changes to an
operating system due to the ease of "cherry-picking" with darcs patches.
Bad of course, that there is no builtin way of tracking file
permissions. (The corresponding issues seem to be all in the "given up"
state.) However, permissions can be dealt with by using hooks. So I
would still suggest to allow / as root directory, at least if this is
not too much effort (didn't look at the code yet).

Fixed by recent changes to the way we interpret command line arguments 
as files relative to the repository root.