On Thu, Dec 27, 2012 at 09:29:37AM -0500, Gene Czarcinski wrote:

OK, this is from inside a shell.  I have a btrfs volume or a btrfs
subvolume on some arbitrary mount mount.  Is there some way to tell
if it is a btrfs volume or a btrfs subvolume that is mounted?

   <nitpick> It's always a subvolume, even if you've mounted the
top-level subvolume (which has subvolid=5). </nipick>

   Right now, no, there isn't any way of telling which subvolume is
mounted at a given location. I think that someone has been working on
it (David?), but I don't think the patches have seen the light of day
yet.

Comment:  It sure would be nice if the btrfs man page corresponded
better to the btrfs code.  Example, the man page says there is a
"btrfs subvolume show" command.  The code disagrees and so does
"btrfs --help"

   The man page doesn't have that in it on my system. Are you running
with an ancient btrfs-progs installation? (Any distribution package
with a date before the end of March 2012 is definitely ancient --
there's still some of them out there).

   Hugo.

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