Rational Developer for System z
PL/I for Windows, Version 8.0, Programming Guide

Defining files for a regional data set

Use a file declaration with the following attributes to define a sequential regional data set:

  declare
    Filename file record
             input | output | update
             sequential
             buffered | unbuffered
             [keyed]
             environment(options);

To define a direct regional data set, use a file declaration with the following attributes:

  declare
    Filename file record
             input | output | update
             direct
             unbuffered
             [keyed]
             environment(options);

File attributes are described in the PL/I Language Reference.

Rational Developer for System z
PL/I for Windows, Version 8.0, Programming Guide