Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!bionet!apple!sun-barr!newstop!male!asilomar!owend
From: owend@asilomar.sun.COM (Owen DeLong SUN IR Workstation Support)
Newsgroups: comp.mail.elm
Subject: Re: elm destroys links!
Message-ID: <768@male.EBay.Sun.COM>
Date: 2 Aug 89 17:25:58 GMT
References: <924@pcsbst.UUCP> <5823@pbhyf.PacBell.COM> <816@ciss.Dayton.NCR.COM>
Sender: news@male.EBay.Sun.COM
Reply-To: owend@asilomar.EBay.Sun.COM (Owen DeLong SUN IR Workstation Support)
Organization: Sun Microsystems, Inc.  Mt. View, Ca.
Lines: 28

In article <816@ciss.Dayton.NCR.COM> tmoore@ciss.Dayton.NCR.COM (Tom.Moore@ciss.Dayton.NCR.COM) writes:
>To recreate it:
>
>1.  Link an existing mail folder to a new name.
I suspect from your discussion that you are using a hard link.
>2.  Fire up elm.
>3.  Change folders to one of the linked folders.
>4.  Delete a message.
>5.  Quit elm and answer yes to the delete messages question.
>6.  Do an ls -i on the subject folders.  Surprise!
>
Based on the above assumption (hard link), here's what I suspect
is happening.  Elm does a selective copy of the old mail file
into a /tmp file.  Then it unlinks the old mail file, and links
the old mail file name to the /tmp file.  This means that process
of updating the mailbox (folder) will run a bit more quickly than
copying the entire file, then selectively copying it back.  If
you were using a symbolic link, chances are that the link would
be untouched, and the real file would be updated, thus keeping
both current.  This is only a guess based on the (small) amount I
know about the internal workings of mailers and UNIX.

For those of you stuck with System V, YATFBB.

Owen DeLong
Sun Microsystems
(Sun doesn't have any idea what I'm talking about, and they
probably don't want to know.)