NetNews Usenet Archive 1992 #31/NN_1992_31.iso/spool/comp/os/vms/19888

Text File | 1992-12-26 | 2.6 KB | 54 lines

Path: sparky!uunet!news.claremont.edu!nntp-server.caltech.edu!SOL1.GPS.CALTECH.EDU!CARL
From: [e-mail] (Carl J Lydick)
Newsgroups: comp.os.vms
Subject: RE: Request help !
Date: 26 Dec 1992 05:42:50 GMT
Organization: HST Wide Field/Planetary Camera
Lines: 40
Distribution: world
Message-ID: <[e-mail]>
References: <[e-mail]>
Reply-To: [e-mail]
NNTP-Posting-Host: sol1.gps.caltech.edu

In article <[e-mail]>, [e-mail] (Jerry Leichter) writes:
>However, if you do that and try to delete 1.DIR, you'll STILL fail, with a
=different error message.  This time, you'll get:  "Directory file is not
=empty".  RMS won't let you delete a directory that contains files.  Normally,
=you could just delete everything from the directory - but the only thing "in"
=[.1] is 2.DIR, which is the same file - so deleting IT fails with yet another
=error message:  "File access conflict" (which, BTW, I can't exactly explain,
=though it makes sense in broad terms).
=
=There IS a solution:  You have to "undo" the synonym you created with
=SET FILE/ENTER.  The "reverse" of this command is SET FILE/REMOVE.  If you
=do:
=
=    $ SET FILE/REMOVE [.1]2.DIR;
=
=you'll find that you are back to where you where after you first created [.1],
=with an empty directory.  If the protection allows it, you can now delete it
=with no further problems.

While what Jerry recommends will work, what he says is not QUITE true.  At
least under VMS v5.4-2, you CAN (apparently) DELETE a non-empty directory.  I
say "apparently" because under recent releases of VMS, the DELETE command
distinguishes between the "primary" directory entry for a file and "secondary"
entries (which is the primary entry is determined by the directory backlink and
filename fields in the file header).  DELETE will now do a "SET FILE/REMOVE"
for secondary directory entries, and does an actual DELETE only for the primary
entry.  So, for example, the following works:
    $    CREATE/DIRECTORY [.1]
    $    SET FILE/ENTER=[.1]2.DIR;1 1.DIR;1
    $    SET PROTECTION=O=RWED 1.DIR;1
    $    DELETE [.1]2.DIR;1
    $    DELETE 1.DIR;1
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: [e-mail] | NSI/HEPnet: SOL1::CARL

Disclaimer:  Hey, I understand VAXen and VMS.  That's what I get paid for.  My
understanding of astronomy is purely at the amateur level (or below).  So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it.  If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.