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To:	rc@archone.tamu.edu
Subject: "whatis" fails to preserve read/write invariance
Date:	Sun, 28 Jun 1992 19:33:36 -0400
From:	Scott Schwartz <schwartz@groucho.cs.psu.edu>
Message-Id: <92Jun28.193400edt.2538@groucho.cs.psu.edu>


The great thing about lisp is that read and write are complementary.
Rc is pretty good about that, but not perfect.  Consider this:

; touch 'x=foo'
; chmod +x 'x=foo'
; './x'=foo  
; whatis './x'
./x=foo
; whatis './x=foo'
./x=foo

Tricked!

In lisp the equals sign in the filename would have been quoted, like
the metacharacter it is.  In rc there is no user level read primative,
so you can't do that.