HP OpenVMS Systems

Overriding SHR=NIL sharing on file open?

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The Question is:

 
In certain situations applications open their logfiles specifying shr=nil (i.e.
 doesn't allow read access to other processes). I need to be able to read any
 file, irrespective of the mode the file is opened in. Is there a way to do this?
 

The Answer is :

 
  Patch the sys$open (or rebuild the image), and permit the sharing?
 
  BACKUP/IGNORE=INTERLOCK will copy files without regard to file system
  locks. However, since it bypasses file system interlocks, there is no
  guarantee that the file will be in a consistent state. For example, the
  file owner, knowing that there are no accessors (since the file was
  opened excluding sharing!) may not have updated the EOF pointer. The
  most recent records may therefore be beyond the apparent EOF mark. You
  can get around that by moving the EOF mark to the end of file (make
  sure the disk doesn't have highwater marking enabled). Naturally you
  may end up with junk at the end of the file.
 
  In general, if you need to be able to share a file, all applications
  accessing the file must cooperate.
 

  

     

     
answer written or last revised on ( 17-APR-2000 )
     
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