/sys$common/syshlp/helplib.hlb MERGE, Output File Qualifiers, /FORMAT, Example  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  $ SORT/KEY=(POS:1,SIZ:80) STATS.DAT SUMMARY.LIS/FORMAT=FIXED:80

      The input file STATS.DAT consists of variable-length records
      that are 80 bytes in length. The /FORMAT qualifier specifies
      that the output file, SUMMARY.LIS, consists of fixed-length
      records.