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From: Eric Sosman <esosman@ieee-dot-org.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: A strange behaviour of a File property
Date: Wed, 16 Nov 2011 08:10:01 -0500
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On 11/16/2011 7:14 AM, Andreas Leitgeb wrote:
>[...]
> If in a VMS-shell you're curently in directory
>    data:[a.b.c.d.e.f.g.h.i.j.k.l.m.n]foo.dir
> and wanted to access the file
>    data:[a.b.c.d.e.f.g.h.i.j.k.l.m.n.bar]xyz.txt
> would you need to specify the complete path to xyz.txt, or
> is there some syntactic pendant to "../bar/xyz.txt" in VMS?

     Sorry; I don't remember.  I *do* remember, though that there
is no such thing as being "in" a directory.  VMS does not have a
Unix-oid notion of "current working directory," but instead has a
"default file specification."  If you hand the system an incomplete
file name, the missing pieces are filled in from the DFS.  Thus,
the resolution of incomplete names is a lexical operation, not a
"navigational" operation.

     Usually this difference does not obtrude itself upon the user's
consciousness, but there are situations where it becomes important.
For example, the "data" in your example could be a "logical name"
with multiple translations: DISK1:[ANDREAS],DISK2:[READONLY], for
example.  You could then tell javac to compile DATA:[.SOURCE]FOO.JAVA
and DATA:[.SOURCE]BAR.JAVA, and javac would happily find your locally-
modified DISK1:[ANDREAS.SOURCE]FOO.JAVA and the still-in-the-repository
DISK2:[READONLY.SOURCE]BAR.JAVA.  It's something like the way a Unix
shell follows the PATH variable, except generalized for all files
instead of being limited just to executables.

     ... but note what this does to the notion of "current directory."
DATA:[.SOURCE]FOO.JAVA and DATA:[.SOURCE]BAR.JAVA have different
parent directories, DISK1:[ANDREAS] and DISK2:[READONLY], respectively.
The idea of being "in" a particular directory may not stand scrutiny.

-- 
Eric Sosman
esosman@ieee-dot-org.invalid