except for one remaining anomalous item, namely...
5 root admin hidden 170 Apr 15 06:52 ..
What is that one all about? (It seems to also employ the belt-and-suspenders approach.)
Well yes and no. That is one of the two directory file refs that every folder (in Unix) must contain.
. refers to the "current" directory (/Volumes/HD2 in this case), and
.. refers to the "parent" directory (/Volumes in this case)
Yes, Apple has chosen to hide the /Volumes folder via a Finder flag.
No, Apple doesn't apply that same "hidden" flag to every '
..' (since the leading dot already does the hiding, from the current folder's perspective).
Actually, we are into a rather mysterious area now, because both
. and
.. are very special items. Once upon a time (in Unix) they could be inspected
directly by uses, using such commands as
cat ..
od -cb ..
and the OS would allow the user to study their contents in the same manner as any "file". But they aren't normal files (although the saying goes: in Unix, everything is a file). They are really part of the directory structure of the filesystem itself. I sorta understand how it all "works" in the
end -- but not all of the underlying implementation details. Plenty of mysteries left to solve.
Believe it or not, i have never used that AppleShowAllFiles trick in Terminal to tweak Finder's plist... but i suspect that both
. and
.. remain abstracted totally out of sight, and can only be "accessed" by users in ways which the system specifically permits us to do.
E.g.,
cd ..
will change directory to the current folder's parent, or
ls ../../*.txt
will list text files in the grand-parent folder.