and found it "the hard way" (i.e. lots of hair pulling followed by aaaaahaaaaaa....)
when one user on a mac mounts a network share, and then another user tries to mount the same share, the share folder (mount point) is INVISIBLE to the first user. EVEN IN TERMINAL. It's just NOT THERE.
Unless you try to make another folder. or remove it. or stat it. Then it acts like it's there but you don't have permission to mess with it. STAT even refuses to act on it. Attempts to stat -f "%u" the file (to get the owner ID, normally this ALWAYS works, even if you can't read the file) fails. (stat is the only good way to tell a plain folder from an active mount point, it's volume id will be different than the volume id of /) I've never seen STAT fail to get a file's properties before. Also, its return code is 1, the same as "file not found". Making this rather tricky to detect via script.
this is in 10.9 at least.
