A Subversion repository contains a file named 'format' (whose contents is
SVN_REPOS__FORMAT_NUMBER) and a file named 'db/format' (whose contents is the
filesystem format, and potentially some additional FS-backend-dependent
Users commonly confuse the two when asked to report the contents of one of them.
svnadmin is confused by this, too (which typically manifests as a cryptic error
message from the invocation 'svnadmin /path/to/repos/db' --- which, yes, is bogus).
At the next opportunity, we should rename these files to have distinct basenames
--- for example, $REPOS/repos-format and $REPOS/db/fs-format.