  Merging Multiple MAIL.MAI Files? 
 The Question is:
 
How do I merge two mail.mai files?
 
 
 The Answer is :
 
  Using the MAIL command FILE/ALL for each folder, most commonly.
  The necessary commands can be invoked from a procedure, with
  one command per folder.
 
  As there is rather more to the MAIL database than the MAIL.MAI file,
  the OpenVMS Wizard would not tend to directly merge multiple MAIL.MAI
  files using the DCL command CONVERT or similar.
 
  There is, however, one situtation where it is reasonable to manually
  and directly merge two mail files: when main mail.mai file is offline
  and inaccessable to incoming MAIL due a recovery from BACKUP or perhaps
  from a CONVERT.
 
  If new mail arrives during a time when the MAIL.MAI file is not
  present, a new MAIL.MAI file will be created.  To MERGE the new
  and the existing file, use the following:
 
   $ RENAME/LOG restored_or_convert_mail.MAI MAIL.MAI  !Latest version
   $ RENAME/LOG MAIL.MAI;-1 temporary.MAI              !Prior version
   $ CONVERT/MERGE/STAT/EXCEPT=problem.MAI temporary.MAI MAIL.MAI
 
  You can perfrom this in-place MERGE because here the corresponding
  user record in the VMSMAIL_PROFILE database matches, and thus the
  directory for the external extentions files holding the larger MAIL
  messages (MAIL$xxxxxxx.MAI) match.
 
  After the MERGE, the temporary file must be deleted or carefully
  relocated, such that no mail operation -- not even a read -- is
  performed on this file, lest the profile or the external extension
  files become unsynchronized.
 
  If you do move a MAIL.MAI from one directory to an other, be sure to
  move all corresponding MAIL$xxxxx.MAI extension files.  (The MAIL
  command SET MAIL_DIRECTORY performs this for you, as it moves the
  MAIL.MAI file and the extension files into the specified subdirectory.)
  The possibiolity of duplicate file names on the extension files is
  the reason why the FILE/ALL command is recommended.
 
  If you do decide to risk your MAIL data -- after having made a known
  good BACKUP -- then you can usually MERGE the larger mail file using:
 
    $ CONVERT/FAST/SORT/STAT/EXCP=problem.MAI -
      left.MAI, right.MAI, middle.MAI new.MAI/FDL=big.fdl
 
  The File Definition Language (FDL) file BIG.FDL would be a
  pre-optimized FDL file.  This file would be created using the
  ANALYZE/RMS command, and the EDIT/FDL command for tuning and
  customization, and would anticipate the requirements of the
  larger, aggregate MAIL.MAI file to be produced by the MERGE.
 
 Answer written or last revised on  16-NOV-2002 
