(DIRECTORY-PATHNAME-AS-FILE "/") can't represent its result properly,

because null strings aren't allowed as pathname names.  So just return
the argument in this case and hope for the best.

diff --git a/v7/src/runtime/unxpth.scm b/v7/src/runtime/unxpth.scm
index 9a5bb9903a7b330a8495783a40c9831d4c9173fc..1047ecd6bde3ec985703589af6c5b5c8d3895332 100644 (file)
--- a/v7/src/runtime/unxpth.scm
+++ b/v7/src/runtime/unxpth.scm
@@ -1,6 +1,6 @@
 #| -*-Scheme-*-
 
-$Id: unxpth.scm,v 14.14 1993/01/12 23:09:10 gjr Exp $
+$Id: unxpth.scm,v 14.15 1993/01/13 09:53:15 cph Exp $
 
 Copyright (c) 1988-1993 Massachusetts Institute of Technology
 
@@ -249,12 +249,12 @@ MIT in each case. |#
                      (pair? (cdr directory)))))
        (error:bad-range-argument pathname 'DIRECTORY-PATHNAME-AS-FILE))
     (if (null? (cdr directory))
-       (%make-pathname (%pathname-host pathname)
-                       'UNSPECIFIC
-                       directory
-                       ""
-                       false
-                       'UNSPECIFIC)
+       ;; Root directory can't be represented as a file, because the
+       ;; name field of a pathname must be a non-null string.  We
+       ;; could signal an error here, but instead we'll just return
+       ;; the original pathname and leave it to the caller to deal
+       ;; with any problems this might cause.
+       pathname
        (parse-name (unparse-directory-component (car (last-pair directory)))
          (lambda (name type)
            (%make-pathname (%pathname-host pathname)