Path: utzoo!attcan!uunet!husc6!bloom-beacon!tut.cis.ohio-state.edu!mailrus!ames!pasteur!ucbvax!VB.CC.CMU.EDU!WEBB%CPWSCA
From: WEBB%CPWSCA@VB.CC.CMU.EDU ("Bryan R. Webb")
Newsgroups: comp.os.vms
Subject: RE: MAIL bug?
Message-ID: <8805160454.AA09442@ucbvax.Berkeley.EDU>
Date: 24 Apr 88 02:13:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 55

> Date: Fri, 15 Apr 88 09:46:10 PST
> From: Peter Scott <PJS@naif.jpl.NASA.GOV>
> Subject: MAIL bug?
> To: info-vax@kl.sri.com
> X-Vms-Mail-To: EXOS%"info-vax@kl.sri.com"
> Message-Id: <880415094610.000023950D2@naif.JPL.NASA.GOV>
>      
> I was just executing a COMPRESS inside MAIL (after having read my INFO-VAX
> messages, needed to clean out the disk), and got an incoming mail message
> notification; I exited from MAIL and deleted my MAIL.OLD file (this was
> all still happening from typed-ahead commands), did a few other things,
> then went back into MAIL, and - surprise - no NEWMAIL folder.  No new
> messages in the MAIL folder.  Message vanished.  Anyone experienced this?
>      
> Peter Scott (pjs%grouch@jpl-mil.jpl.nasa.gov)
 

I've also been the situation before where I was compressing my MAIL.MAI
file at the very moment mail arrived, but my mail was not lost because I
was not so hast to delete my MAIL.OLD file. 

The session went something as follows:

   MAIL> COMPRESS
   
   %MAIL-S-CREATED, USR$ROOT:[WEBB.MAIL]MAIL_004A_COMPRESS.TMP;1 created
   New mail on node COBRA from STREIX::STUBBORN
   %MAIL-S-COPIED, USR$ROOT:[WEBB.MAIL]MAIL.MAI;1 copied to 
      	        USR$ROOT:[WEBB.MAIL]MAIL_004A_COMPRESS.TMP;1 (327 records)
   %MAIL-S-RENAMED, USR$ROOT:[WEBB.MAIL]MAIL.MAI;1 renamed to 
      		USR$ROOT:[WEBB.MAIL]MAIL.OLD;1
   %MAIL-S-RENAMED, USR$ROOT:[WEBB.MAIL]MAIL_004A_COMPRESS.TMP;1 renamed to 
      		USR$ROOT:[WEBB.MAIL]MAIL.MAI;1
   
   MAIL> 

You see, the system delivered the mail while the original MAIL.MAI file
was still in place, but apparently put it in a place the compression had
already passed or just couldn't find.  Then, as the compression continued,
the MAIL.MAI file that my new message went to was now MAIL.OLD (and the
MAIL_aaaa_COMPRESS.TMP file without the new message became my MAIL.MAI).
All I had to do was to SET FILE MAIL.OLD in MAIL and read the new message
there. 

I don't think that this is a bug, and that it was handled pretty well.
About the only other way it could have been handled would have been to
make the system wait until the MAIL.MAI file was no longer locked by the
compression to deliver the message, but that would that would probably be
unreasonable to the sender (and people hate to wait). 

--Bryan Webb
User Consultant
Pittsburgh Supercomputing Center

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