🚀 go-pugleaf

# 	1) dirfile is NOT a directory but a file (created by rrestore)

I don't know about the rest of your article, but this I can answer: it knows
it's trying to open a dirfile, it just copied it in from the tape.  The ndir(3)
routines don't care if it's really a directory, just as long as the format is
compatible.  The routines are read-only since they run in user-mode; if you
point 'em at a file that happens to look like a directory, they work fine.

(on my 4.3bsd machine:)
===
vixie@beast-> /bin/cp . foo
cp: .: Is a directory (copying as plain file).
vixie@beast-> /bin/ls -f foo
.            .rhosts      .profile     .mh_profile  .uwmrc       foo
..           ueg          .joverc      .signature   ftpd
Etc          .cshrc       .mailrc      .Xres        routed
===
-- 
Paul Vixie
Work:    vixie@decwrl.dec.com    decwrl!vixie    +1 415 853 6600
Play:    paul@vixie.sf.ca.us     vixie!paul      +1 415 864 7013