I thought that one use of mount_union was to be able to layer read/write filesystem over a read/only filesystem, such that writing would create a file in the upper filesystem, and reading would read an unchanged file from the lower one. Is this correct?
A quick experiment on -current/amd64: # mkdir /var/upper # mkdir /var/lower # touch /var/lower/file # mount_union /var/upper /var/lower # mount ... <above>:/var/upper on /var/lower type union (local) # ls /var/upper # ls /var/lower file I would have expected to see file in /var/upper # touch /var/upper/another # ls /var/upper another # ls /var/lower another file I would not have expected to see another in /var/lower How are union mounts meant to work? Cheers, Patrick
