Date   : Thu, 12 Apr 1984 10:34:00 EST
From   : "John C. Klensin" <Klensin@MIT-MULTICS.ARPA>
Subject: use of lower case for status bits

Some things, especially misbehaving file transfer programs, can succeed
in creating objects with mixed-case, or lower-case, objects in the CP/M
file system.  The resulting objects are very hard to identify (since
much software tries to automatically upper-case the names), and even
harder to get rid of (since the CP/M resident commands all map whatever
is typed to upper case before trying to erase, rename, or whatever).

So, if you use a case-shift to show status, you will need both
 - a way to indicate when the lower case character is lower case because
it is there and/or
 - a way to caution the reader that the name really contains lower case.
  Those requirements might lead to the reinvention of highlighting.

  Now, you could probably safely ignore this for some programs (such as
MDM7), but it is probably quite important that things like SD and XDIR
tell what is really there, so, without precisely what you are trying to
avoid, it does not make a good general convention -- I want
directory-inspecting programs to tell me what is in the directory as
their absolute first priority.

I am surprised that the UNIX community has not noticed this little
problem arising occasionally as well (if, indeed, they have not).