HP OpenVMS Systems

CONVERT and Export RMS Data?

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The Question is:

 
How can I convert then export an RMS data file for importing as a txt file?
 

The Answer is :

 
  RMS data file are just blobs (records) of bytes (raw data), as far as
  RMS is concerned.  Whether there is any meaning to those bits is entirely
  up to the application. The application may choose to interpret the bits
  as text, integers, floating point values, and so one.  (The only place
  where RMS puts some meaning onto the data is where a range of bytes are
  defined as a key in an indexed file, and RMS will then try to select the
  right sorting order based on the data.)
 
  So, if your application is a text editor and the data is pure text,
  then no conversion is likely needed.  The same holds for "fixed length
  record, fixed columns, display only" style often seen in commercial
  (typically COBOL) applications.  In rare cases, you may want to convert
  an indexed or relative file to sequential through a simple DCL command
  such as the following:
 
    TYPE/OUTPUT=output input
 
  or:
 
    CONVERT/FDL=NL: input output
 
  but this conversion is generally optional.
 
  If the files contain "fields" of binary data (integer, floating point,
  etc.), you will need an application to overlay that record structure
  onto the data.  Often this is readily accomplished using a "report
  generating" function in the application engine or language.  Sometimes
  it means taking an existing sample program that already knows how to
  read the file -- an application that already understands the record
  layout -- and change it to:
 
    BASIC:
      PRINT
 
    COBOL:
      DISPLAY
 
    DCL:
      WRITE SYS$OUTOUT F$CVSI...
 
  the fields of the record.
 
  For larger transfers or for conversion projects or for mixed system
  environments, it may appropriate to select a specific data reporting
  or migration or remote access tools like one of the many ODBC-based
  products that may help to make "live" RMS file data visible on the
  target machines through remote SQL calls.
 
  If static text files are all that is needed for the data transfer,
  then the OpenVMS Wizard prefers to use the Datatrieve tool, as it has
  very powerful 4GL data selection and formatting functions available.
 
  Also be aware that transfers to or from certain computing platforms
  can require you to consider the endian-ness of the data involved, and
  to potentially become involved in byte-swizzling operations within
  the items in the data.
 

  

     

     
answer written or last revised on ( 7-DEC-1999 )
     
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