in what? SQL? RPG? …
You don’t typically see the relative record number, it is a records placement with in a physical file. Is it the first record or the fifth record or the 500th record. That is its relative record number from the beginning of the file.
Hope this helps,
In RPG, add a file info data structure to the file whose RRN you wish to see. One of the fields in the data structure will contain the RRN of the most recently accessed record.
In SQL, try Select rrn(fileName), fieldA, fieldB from fileName.