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Application Design Assistance? (File access)

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The Question is:

 
I have a monitor type background program which at 1 sec intervals processes
 some dynamic input specified by some configuration info. loaded from about 500
 smaller files all contained in a single directory. The files are static except
 for an occasional upd
ate of one or more files by an editor running in another process. The problem
 is that I need to promptly incorporate the updates in the program without stop
 and restart of the program. And I cannot change the editor code. Checking the
 timestamp of all the
 files every 1 sec. is too heavy. None of the file attributes of the directory
 file such as the timestamps appear to change when a file in the directory is
 updated. How can I quickly determine if one or more of the files have changed.
 I don't need to know
 which one(s). I can just reload them all (but not every 1 sec). Doing a "$
 DIR/FULL" I noticed a line saying "file monitoring not enabled". I searched
 for this attribute in the OpenVMS doc but got no results.
Thank you very much.
 
 


The Answer is :

 
  Please contact Compaq professional services or (if this application
  is for resale) the Compaq Solutions Alliance (CSA) organization for
  further assistance with the design and implementation of your
  particular application.
 
  That said, the OpenVMS Wizard would probably use a design based on
  the lock manager -- a "doorbell" lock would be used to notify all
  applications with an interest in updates, rather than the use of a
  scheme based on polling file contents or file timestamps.
 
  For details on file monitoring and file statistics collection, please
  see the MONITOR utility documentation.  (This is a statistics collection
  interface within MONITOR, and is not intended and not likely useful for
  your intended task.)
 

answer written or last revised on ( 9-JUL-2001 )

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