HP OpenVMS Systems

Counting records in RMS file?

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The Question is:

 
Using DCL or perhaps TPU commands, I am trying to determine the number of
 records in a text file.
 
I have been reading the file from beginning to end while incrementing a
 counter.  I figured that there has to be a better way.  This seems very
 inefficient.  Especially if the text file contains thousands of records.
 
Can you help me out or at least point me in the right direction?
 
Thank you, Mr. Wizard!
 

The Answer is :

 
  OpenVMS does not maintain a count of the total records within a file.
 
  Accordingly, you will have to open the file and count the records,
  either explicitly -- via a loop containing explicit record access
  operations, or implicitly -- via the record operations that occur
  within DCL commands such as CONVERT/SHARE/STATISTICS or
  SEARCH/STATISTICS.
 
  Starting with OpenVMS Alpha V7.2 and only with the ODS-5 volume
  structure, RMS will maintain a FILE_LENGHT_HINT attribute.  This
  length hint includes the number of records and the number of bytes
  written to the file.
 
  The hint is available via f$file(filename,"file_length_hint") from
  DCL, and via the XABITM structure and the XAB$_FILE_LENGTH_HINT
  attribute from a program.  Details on this are in the Record
  Management Reference Manual.
 
  From DCL, the output of f$file(filename,"file_length_hint") is a
  comma-separated pair of numbers enclosed in paratheses, the first
  number is the record count and the second is the data byte count.
  A value of -1 indicates an invalid or unknown value.
 

  

     

     
answer written or last revised on ( 7-AUG-2001 )
     
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